Device and method for testing POE (Power Over Ethernet) system

Abstract

The invention belongs to the technical field of POE power supply equipment, and particularly relates to a POE system test device and method, the test device comprises a processing module, a port voltage detection module and a PSE test module; the port voltage detection module is connected with the processing module and a port of the PSE; the PSE test module comprises a characteristic impedance test circuit and a load variable circuit, the characteristic impedance test circuit is connected with a port of the PSE power supply equipment, one end of the load variable circuit is connected with the characteristic impedance test circuit, and the other end of the load variable circuit is connected with the processing module; the test device can quickly identify a standard POE system or a non-standard POE system, can perform grading standard confirmation and actual output power confirmation on PSE power supply equipment, and is safe, reliable and low in cost.

Description

Technical Field

[0001] The present application relates to the technical field of POE power supply equipment, and in particular to a testing device and method for POE power supply equipment. Background Art

[0002] The POE (Power Over Ethernet) Ethernet power supply system consists of two parts: PSE (Power Sourcing Equipment) and PD (Power Device). The POE system can use the existing Ethernet Cat.5, Cat.6 and other wiring infrastructure to provide DC power supply services for IP-based PD terminals (such as IP phones, wireless LAN access points AP, network cameras, etc.) without affecting the transmission of data signals. Since the POE system only needs one network cable to complete power supply and data transmission at the same time, it effectively simplifies network wiring, reduces infrastructure installation and daily operating costs, and has been widely used.

[0003] Due to cost and other reasons, there are two power supply systems in the society, standard POE and non-standard POE. Once a standard PD device is connected to a non-standard POE system, it is easy to cause damage to the PD device or the non-standard POE device port. In addition, if the PD cannot be powered on and work normally in the standard POE system, it is difficult to determine whether it is a fault of the PD device itself or the PSE power supply classification standard or output power does not meet the requirements.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] In view of at least one of the above technical problems, the present application provides a testing device and method for a POE power supply device.

[0006] In a first aspect, the present application provides a test device for a POE system, which is connected to a port of a PSE power supply device, and the test device includes: a processing module, a port voltage detection module, and a PSE test module;

[0007] The port voltage detection module is connected to the processing module and the port of the PSE power supply device;

[0008] The processing module collects the potential of the port voltage detection module, and determines whether the port voltage of the PSE power supply device is greater than the preset voltage according to the potential of the port voltage detection module; if so, the POE system is a non-standard system;

[0009] The PSE test module includes: a characteristic impedance test circuit and a load variable circuit, the characteristic impedance test circuit is connected to the port of the PSE power supply device, one end of the load variable circuit is connected to the characteristic impedance test circuit, and the other end of the load variable circuit is connected to the processing module;

[0010] The characteristic impedance test circuit outputs an indication signal to the PSE power supply equipment, and the indication signal is used for the PSE power supply equipment to respond and determine whether the characteristic impedance test circuit has a characteristic resistance; if it has a characteristic resistance, a hierarchical verification is performed;

[0011] The load variable circuit receives the classification inspection signal and generates an identification signal according to the classification inspection signal; the processing module receives the identification signal and responds to control the load variable circuit to adjust the load; the load variable circuit outputs the classification current signal to the PSE power supply device;

[0012] The processing module receives the power signal and responds, controlling the load variable circuit to adjust the load. The power signal is output by the PSE power supply device according to the graded current signal. The processing module calculates the current value flowing through the load variable circuit and compares it with the preset graded current value. If they are the same, the graded verification is completed.

[0013] One of the above technical solutions has at least one of the following advantages or beneficial effects: the test device can quickly identify a standard POE system or a non-standard POE system, and can confirm the classification standard and actual output power of the PSE power supply equipment. The entire device is safe, reliable and low-cost.

[0014] In some possible implementations, the port voltage detection module includes: multiple parallel detection circuits, the first end of the detection circuit is connected to the pin of the port of the PSE power supply device, the second end of the detection circuit is connected to the reference voltage, the third end of the detection circuit is connected to the processing module, and the third end of the detection circuit is used for the processing module to collect the potential of the detection circuit.

[0015] In some possible implementations, the detection circuit includes: a first voltage-dividing resistor, a second voltage-dividing resistor and an acquisition node, the first end of the first voltage-dividing resistor is connected to a reference voltage and another detection circuit, the second end of the first voltage-dividing resistor is connected to the acquisition node, the acquisition node is connected to the processing module, the first end of the second voltage-dividing resistor is connected to the acquisition node, and the second end of the second voltage-dividing resistor is connected to a port of a PSE power supply device.

[0016] In some possible implementations, the characteristic impedance verification circuit includes: a first switching circuit, a second switching circuit, a unidirectional circuit, a characteristic resistance circuit, a first cutoff circuit and a second cutoff circuit, the first end of the first switching circuit and the first end of the second switching circuit are commonly connected to the second end of the unidirectional circuit, the second end of the first switching circuit and the second end of the second switching circuit are respectively connected to the port of the PSE power supply equipment, the first end of the characteristic resistance circuit is connected to the first end of the unidirectional circuit, the first end of the first cutoff circuit and the first end of the second cutoff circuit are commonly connected to the second end of the characteristic resistance circuit, the second end of the first cutoff circuit is connected to the second end of the first switching circuit, the second end of the second cutoff circuit is connected to the second end of the second switching circuit, and the first end of the characteristic resistance circuit is connected to the load variable circuit.

[0017] In some possible implementations, the first switch circuit includes: a seventh transistor and a thirteenth transistor, the collector of the seventh transistor is connected to the first pin of the port of the PSE power supply device, the emitter of the seventh transistor is connected to the second end of the unidirectional circuit, the base of the seventh transistor is connected to the first cut-off circuit, the collector of the thirteenth transistor is connected to the second pin of the port of the PSE power supply device, the emitter of the thirteenth transistor is connected to the second end of the unidirectional circuit, and the base of the thirteenth transistor is connected to the first cut-off circuit;

[0018] The second cutoff circuit includes: a ninth diode and a tenth diode, the anode of the ninth diode and the anode of the tenth diode are connected to the second end of the characteristic resistance circuit, the cathode of the ninth diode and the cathode of the tenth diode are connected to the second switch circuit respectively, the cathode of the ninth diode is connected to the sixth pin of the port of the PSE power supply equipment, and the cathode of the tenth diode is connected to the third pin of the port of the PSE power supply equipment.

[0019] In some possible implementations, the second switch circuit includes: an eleventh transistor and a twelfth transistor, the collector of the eleventh transistor is connected to the third pin of the port of the PSE power supply device, the emitter of the eleventh transistor is connected to the second end of the unidirectional circuit, the base of the eleventh transistor is connected to the second cut-off circuit, the collector of the twelfth transistor is connected to the sixth pin of the port of the PSE power supply device, the emitter of the twelfth transistor is connected to the second end of the unidirectional circuit; the base of the twelfth transistor is connected to the second cut-off circuit;

[0020] The first cutoff circuit includes: a first diode and an eighth diode, the anode of the first diode and the anode of the eighth diode are connected to the second end of the characteristic resistance circuit, the cathode of the first diode is connected to the second pin of the port of the PSE power supply device, and the cathode of the eighth diode is connected to the first pin of the port of the PSE power supply device.

[0021] In some possible implementations, the characteristic resistance circuit includes: a sixth resistor and a seventh resistor, the first end of the sixth resistor is connected to the first end of the unidirectional circuit, the first end of the seventh resistor is connected to the second end of the sixth resistor, the second end of the seventh resistor is connected to the first end of the first cut-off circuit and the first end of the second cut-off circuit, the first end of the load variable circuit is connected to the first end of the sixth resistor, and the second end of the load variable circuit is connected to the first end of the seventh resistor.

[0022] In some possible implementations, the variable load circuit includes: an identification circuit, an electronic load circuit and a third switch circuit, the first end of the identification circuit is connected to the processing module and the first end of the electronic load circuit respectively, the second end of the identification circuit and the second end of the electronic load circuit are connected to the characteristic resistance circuit respectively, and the third switch circuit is connected between the processing module and the electronic load circuit.

[0023] In some possible implementations, the identification circuit includes: a fourth operational amplifier, the fourth operational amplifier non-inverting input terminal is connected to the characteristic resistance circuit, the fourth operational amplifier inverting input terminal is connected to the reference voltage, and the fourth operational amplifier output terminal is respectively connected to the processing module and the first end of the electronic load circuit.

[0024] In a second aspect, the present application provides a test method for a POE system, which is implemented by a test device, and the test method includes:

[0025] The processing module collects the potential of the port voltage detection module, and determines whether the port voltage of the PSE power supply device is greater than the preset voltage according to the potential of the port voltage detection module; if so, the POE system is a non-standard system;

[0026] The characteristic impedance test circuit outputs an indication signal to the PSE power supply equipment, and the indication signal is used for the PSE power supply equipment to respond and determine whether the characteristic impedance test circuit has a characteristic resistance; if it has a characteristic resistance, a hierarchical verification is performed;

[0027] The load variable circuit receives the classification inspection signal and generates an identification signal according to the classification inspection signal; the processing module receives the identification signal and responds to control the load variable circuit to adjust the load; the load variable circuit outputs the classification current signal to the PSE power supply device;

[0028] The processing module receives the power signal and responds, controlling the load variable circuit to adjust the load. The power signal is output by the PSE power supply device according to the graded current signal. The processing module calculates the current value flowing through the load variable circuit and compares it with the preset graded current value. If they are the same, the graded verification is completed.

[0029] The present application is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the structure of a testing device for a POE system provided in an embodiment of the present application;

[0032] Figure 2 for Figure 1 Signal flow diagram of the PSE test module;

[0033] Figure 3 for Figure 1 Schematic diagram of the middle port voltage detection module;

[0034] Figure 4 for Figure 3 A schematic diagram of one of the detection circuits;

[0035] Figure 5 for Figure 1 Circuit diagram of the middle port voltage detection module;

[0036] Figure 6 for Figure 1 Partial schematic diagram of characteristic impedance test circuit;

[0037] Figure 7 for Figure 6 The circuit diagram of the characteristic impedance test circuit;

[0038] Figure 8 for Figure 1 Schematic diagram of medium load variable circuit;

[0039] Fig. 9 for Figure 8 Circuit diagram of medium load variable circuit; DETAILED DESCRIPTION

[0040] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0041] Figure 1 A schematic diagram of the structure of a testing device for a POE system provided in an embodiment of the present application; Figure 2for Figure 1 The signal flow diagram of the PSE test module in;

[0042] See also Figure 1 In some embodiments, the test device is connected to the port of the PSE power supply device. In actual applications, when not in use, the test device is an independent device. When in use, the test device is connected to the RJ45 port of the PSE power supply device through an RJ45 harness. The test device can quickly identify a standard POE system or a non-standard POE system, and can confirm the classification standard and actual output power of the PSE power supply device. The entire device is safe, reliable and low-cost.

[0043] See also Figure 1 The testing device includes: a processing module 100, a port voltage detection module 200 and a PSE testing module 300. The processing module 100, the port voltage detection module 200 and the PSE testing module 300 are all integrated in the testing module.

[0044] The port voltage detection module 200 is connected to the processing module 100 and the port of the PSE power supply device. The port voltage detection module 200 is used to determine whether the PSE power supply device is connected to a non-standard POE system. The processing module 100 collects the potential of the port voltage detection module 200, and determines whether the port voltage of the PSE power supply device is greater than the preset voltage according to the potential of the port voltage detection module 200; if so, the POE system is a non-standard system. Specifically, the preset voltage is 10V. The value of 10V is mainly to ensure the measurement accuracy and prevent misjudgment. A voltage greater than 10V is easy to damage ordinary network devices that do not have POE functions, and a lower voltage is not easy to damage the access device.

[0045] In actual application, the test device is connected to the RJ45 port of the PSE power supply equipment through the RJ45 wiring harness; the port voltage detection module 200 detects whether the port has a DC voltage greater than 10V; if so, it indicates that a non-standard POE system exists; if not, the next step of detection is carried out, namely, the classification standard verification and the actual output power verification.

[0046] Please continue reading Figure 1 The PSE test module 300 is connected to the processing module 100 and the port of the PSE power supply device. The PSE test module 300 is used to verify the classification standard and the actual output power. The PSE test module 300 includes: a characteristic impedance test circuit 310 and a load variable circuit 320. The characteristic impedance test circuit 310 is connected to the port of the PSE power supply device, one end of the load variable circuit 320 is connected to the characteristic impedance test circuit 310, and the other end of the load variable circuit 320 is connected to the processing module 100;

[0047] See also Figure 2 In actual application, the PSE power supply device sends a pulse signal to the test device; the characteristic impedance verification circuit 310 receives the pulse signal and generates an indication signal based on the pulse signal; the characteristic impedance verification circuit 310 outputs an indication signal to the PSE power supply device, and the indication signal is used for the PSE power supply device to respond and determine whether the characteristic impedance verification circuit 310 has a characteristic resistance; if the characteristic resistance is present, a hierarchical verification is performed;

[0048] The load variable circuit 320 receives the classification check signal and generates an identification signal according to the classification check signal; the processing module 100 receives the identification signal and responds to control the load variable circuit 320 to adjust the load; the load variable circuit 320 outputs a classification current signal to the PSE power supply device;

[0049] The processing module 100 receives the power signal and responds to control the load variable circuit 320 to adjust the load. The power signal is output by the PSE power supply device according to the grading current signal. The processing module 100 calculates the current value flowing through the load variable circuit 320 and compares it with the preset grading current value. If they are the same, the grading verification is completed.

[0050] Figure 3 for Figure 1 A schematic diagram of a middle port voltage detection module 200; Figure 4 for Figure 3 A schematic diagram of one of the detection circuits; Figure 5 for Figure 1 Circuit diagram of the middle port voltage detection module 200;

[0051] See also Figures 3 to 5 In some embodiments, the port voltage detection module 200 includes: a plurality of detection circuits connected in parallel. Specifically, the number of the detection circuits is eight, and each detection circuit corresponds to a pin of a port of a PSE power supply device.

[0052] The first end of the detection circuit is connected to the pin of the port of the PSE power supply device, the second end of the detection circuit is connected to the reference voltage, the third end of the detection circuit is connected to the processing module 100, and the third end of the detection circuit is used for the processing module 100 to collect the potential of the detection circuit. Among them, the reference voltage is provided by the processing module 100, and the specific value of the reference voltage is 2.5V.

[0053] Since the structures of the eight detection circuits are the same, they are not described one by one here, and one detection circuit is taken as an example. The detection circuit may include: a first voltage-dividing resistor, a second voltage-dividing resistor and a collection node, the first end of the first voltage-dividing resistor is connected to the reference voltage and another detection circuit, the second end of the first voltage-dividing resistor is connected to the collection node, the collection node is connected to the processing module 100, the first end of the second voltage-dividing resistor is connected to the collection node, and the second end of the second voltage-dividing resistor is connected to the port of the PSE power supply device.

[0054] See also Figure 5 For example, when the port of the PSE power supply device has a DC voltage U input, and P1 is the positive pole and P2 is the negative pole, P1, resistor R40, resistor R27, resistor R28, resistor R41, and P2 are connected in series to form a loop. Taking VREF as the reference point, according to Ohm's theorem, the potential of ADC1 is 3.5V and the potential of ADC2 is 1.5V.

[0055]

[0056] P3, P4, P5, P6, P7, and P8 have no voltage input, so the potentials of ADC3, ADC4, ADC5, ADC6, ADC7, and ADC8 are all VREF, which is 2.5 V. Therefore, by measuring the voltage values ​​of ADC1 to ADC8, we can calculate how much voltage exists in P1 and P2, and know that P1 is positive and P2 is negative. P3, P4, P5, P6, P7, and P8 ports have no voltage input.

[0057] Figure 6 for Figure 1 A partial schematic diagram of a characteristic impedance test circuit 310; Figure 7 for Figure 6 2 is a circuit diagram of a characteristic impedance detection circuit 310.

[0058] See also Figure 6 and Figure 7 The characteristic impedance verification circuit 310 may include: a first switch circuit, a second switch circuit, a unidirectional circuit, a characteristic resistance circuit, a first cutoff circuit and a second cutoff circuit. The first end of the first switch circuit and the first end of the second switch circuit are commonly connected to the second end of the unidirectional circuit. The second end of the first switch circuit and the second end of the second switch circuit are respectively connected to the port of the PSE power supply device. The first end of the characteristic resistance circuit is connected to the first end of the unidirectional circuit. The first end of the first cutoff circuit and the first end of the second cutoff circuit are commonly connected to the second end of the characteristic resistance circuit. The second end of the first cutoff circuit is connected to the second end of the first switch circuit. The second end of the second cutoff circuit is connected to the second end of the second switch circuit. The first end of the characteristic resistance circuit is connected to the load variable circuit 320.

[0059] The first switch circuit and the second switch circuit have the same circuit structure. The first cutoff circuit and the second cutoff circuit have the same circuit structure.

[0060] It is worth noting that the characteristic impedance detection circuit 310 has two identical parts, one of which is as follows: Figure 6 and Figure 7As shown, one part is connected between P1, P2, P3, and P6 of the ports of the PSE power supply equipment, and the other part is connected between P4, P5, P7, and P8 of the ports of the PSE power supply equipment, which will not be repeated here.

[0061] Please continue reading Figure 6 In actual applications, taking the P1, P2, P3, and P6 ports of the PSE power supply equipment as an example, when the test device is connected to a non-standard POE system or the network wiring harness is connected incorrectly, for example, the P1 input voltage of the PSE power supply equipment port is positive and the P2 input voltage is negative, or the P1 input voltage is negative and the P2 input voltage is positive, the first switch circuit is in a closed state, so no loop is formed between P1 and P2, thereby realizing the polarity protection function. Similarly, the P3 and P6 ports of the PSE power supply equipment are protected by the second switch circuit. There are switch circuit protections between P4 and P5 ports, and between P7 and P8 ports of the PSE power supply equipment, which will not be repeated here.

[0062] For details, please continue to see Figure 7 The first switch circuit may include: a seventh transistor and a thirteenth transistor, the collector of the seventh transistor is connected to the first pin of the port of the PSE power supply device, the emitter of the seventh transistor is connected to the second end of the unidirectional circuit, the base of the seventh transistor is connected to the first cut-off circuit, the collector of the thirteenth transistor is connected to the second pin of the port of the PSE power supply device, the emitter of the thirteenth transistor is connected to the second end of the unidirectional circuit, and the base of the thirteenth transistor is connected to the first cut-off circuit;

[0063] The second cutoff circuit may include: a ninth diode and a tenth diode, the anode of the ninth diode and the anode of the tenth diode are connected to the second end of the characteristic resistance circuit, the cathode of the ninth diode and the cathode of the tenth diode are respectively connected to the second switch circuit, the cathode of the ninth diode is connected to the sixth pin of the port of the PSE power supply equipment, and the cathode of the tenth diode is connected to the third pin of the port of the PSE power supply equipment.

[0064] The second switch circuit may include: an eleventh transistor and a twelfth transistor, the collector of the eleventh transistor is connected to the third pin of the port of the PSE power supply device, the emitter of the eleventh transistor is connected to the second end of the unidirectional circuit, the base of the eleventh transistor is connected to the second cut-off circuit, the collector of the twelfth transistor is connected to the sixth pin of the port of the PSE power supply device, the emitter of the twelfth transistor is connected to the second end of the unidirectional circuit; the base of the twelfth transistor is connected to the second cut-off circuit;

[0065] The first cutoff circuit may include: a first diode and an eighth diode, the anode of the first diode and the anode of the eighth diode are connected to the second end of the characteristic resistance circuit, the cathode of the first diode is connected to the second pin of the port of the PSE power supply device, and the cathode of the eighth diode is connected to the first pin of the port of the PSE power supply device.

[0066] The unidirectional circuit may include: an eleventh diode.

[0067] The characteristic resistance circuit may include: a sixth resistor and a seventh resistor, the first end of the sixth resistor is connected to the first end of the unidirectional circuit, the first end of the seventh resistor is connected to the second end of the sixth resistor, the second end of the seventh resistor is connected to the first end of the first cutoff circuit and the first end of the second cutoff circuit, the first end of the load variable circuit 320 is connected to the first end of the sixth resistor, and the second end of the load variable circuit 320 is connected to the first end of the seventh resistor.

[0068] It is worth noting that the sixth resistor is 5KΩ and the seventh resistor is 20KΩ, so the total resistance of the characteristic resistor circuit is 25KΩ, and the combined characteristic resistor meets the requirements of the IEEE.802.3af\at\bt protocol.

[0069] In actual applications, the PSE power supply equipment sends a positive pulse signal to the first pin (i.e., P1) and the second pin (i.e., P2) of the port, the sixth pin (i.e., P6) and the third pin (i.e., P3) of the port are both referenced to the ground, the eleventh transistor and the twelfth transistor are turned on, the seventh transistor and the thirteenth transistor are turned off, the first diode and the eighth diode are turned off, and the ninth diode and the tenth diode are turned on. The current flows from P1 and P2 into the collector of the seventh transistor and the collector of the thirteenth transistor, and flows out from the emitter of the seventh transistor and the emitter of the thirteenth transistor, and then passes through the eleventh diode, the sixth resistor and the seventh resistor, and flows into the ninth diode and the tenth diode respectively, and finally flows out of the ninth diode to the sixth pin (i.e., P6) of the port, and flows out of the tenth diode to the third pin (i.e., P3) of the port, thereby completing the characteristic resistance inspection.

[0070] The above example only shows the process in which the PSE power supply equipment sends a positive pulse signal to the first pin of the port (ie, P1) and the second pin of the port (ie, P2).

[0071] Combination Figure 2 In the above example, the current flows out of the ninth diode to the sixth pin of the port (ie, P6) and flows out of the tenth diode to the third pin of the port (ie, P3). The PSE power supply device receives the indication signal to identify whether the characteristic impedance verification circuit 310 has a characteristic resistor.

[0072] Figure 8 for Figure 1 A schematic diagram of a load variable circuit 320; Fig. 9 for Figure 8 Circuit diagram of the load variable circuit 320.

[0073] See also Figure 2 , Figure 8 In some examples, the variable load circuit 320 includes: an identification circuit, an electronic load circuit and a third switch circuit, the first end of the identification circuit is connected to the processing module 100 and the first end of the electronic load circuit respectively, the second end of the identification circuit and the second end of the electronic load circuit are connected to the characteristic resistance circuit respectively, and the third switch circuit is connected between the processing module 100 and the electronic load circuit.

[0074] In actual application, the PSE power supply equipment sends a grading check signal to the test device, and the grading check signal passes through the characteristic impedance detection circuit 310 and is received by the identification circuit; the identification circuit generates an identification signal based on the grading check signal, and sends the identification signal to the processing module 100; the processing module 100 receives and responds to the identification signal, and controls the electronic load circuit to adjust the load; the electronic load circuit outputs a grading current signal to the PSE power supply equipment; the PSE power supply equipment outputs a corresponding power signal according to the grading current signal; the processing module 100 detects the power signal, and controls the electronic load circuit to adjust the load according to the power signal; the processing module 100 calculates the current value flowing through the electronic load circuit, and compares it with the preset grading current value; if yes, the verification is completed.

[0075] In the above verification process, the processing module 100 controls the electronic load circuit to adjust the load, thereby controlling the input current and realizing the electronic load.

[0076] It is worth noting that the preset grading current value has three levels. The first level is 6.5mA, corresponding to an output power of 4W; the second level is 14.5mA, corresponding to an output power of 6.7W; the third level is 23mA, corresponding to an output power of 13W.

[0077] Continue reading Fig. 9 In some embodiments, the identification circuit may include: a fourth operational amplifier, wherein the fourth operational amplifier non-inverting input terminal is connected to the characteristic resistance circuit, the fourth operational amplifier inverting input terminal is connected to the reference voltage, and the fourth operational amplifier output terminal is respectively connected to the processing module 100 and the first end of the electronic load circuit.

[0078] The electronic load circuit may include: a first field effect transistor, a first operational amplifier, a third operational amplifier, a variable resistance unit, a fourth resistor and a fifty-second resistor, wherein the first operational amplifier non-inverting input terminal is respectively connected to the fourth operational amplifier and the third switch circuit, the first end of the first field effect transistor is connected to the output end of the first operational amplifier, the second end of the first field effect transistor is connected to the characteristic resistance circuit, the first end of the fourth resistor is connected to the third end of the first field effect transistor, the second end of the fourth resistor is grounded, the third operational amplifier non-inverting input terminal is connected to the first end of the fourth resistor, the third operational amplifier inverting input terminal is connected to the second end of the fourth resistor through the fifty-second resistor, and the first end of the variable resistance unit is respectively connected to the inverting input end of the first operational amplifier and the output end of the third operational amplifier.

[0079] In the electronic load circuit, the input circuit is I=VOUT / [R4×(1+RF / R52)], where RF is the resistance value of the variable resistor unit. Therefore, the processing module 100 controls the resistance value of the variable resistor unit to control the input current and realize the electronic load.

[0080] For example, after passing the characteristic impedance detection, the PSE power supply device will send a grading inspection signal (voltage value is 18.5V) to the test device. Since the sixth resistor has a resistance value of 5KΩ and the seventh resistor has a resistance value of 20KΩ, it can be known from Ohm's law that VH=18.5V×(5 / 25)=3.7V. At this time, VH=3.7V is greater than VREF 2.5V. The fourth operational amplifier outputs VOUT=5V, which means that an identification signal is output to the processing module 100. When the processing module 100 receives the identification signal, it can be known that the PSE power supply device has started to perform a grading current check. Subsequently, the processing module 100 controls the variable resistance unit to select the required resistance value and closes the third switch circuit. At this time, the current source configuration is completed and the grading verification begins.

[0081] Assuming that the PSE power supply device under test can output the third level of 13W power, it is necessary to provide a load with a current of 23mA in the classification current check. Specifically, the PSE power supply device outputs a classification check signal (18.5V), the current flows to the ground through the first field effect tube and the fourth resistor, the voltage of the fourth resistor rises, and the voltage output by the third operational amplifier also rises. Since the voltage at the in-phase input terminal of the first operational amplifier is VOUT=5 and remains unchanged, the voltage at the reverse input terminal rises, and the output voltage VQ of the first operational amplifier will decrease. Due to the decrease in VQ, the turn-on voltage of the first field effect tube decreases, which increases the internal resistance of the first field effect tube, thereby reducing the current flowing through the first field effect tube and the fourth resistor, forming a negative feedback. According to the "virtual short and virtual disconnection", the input current I = VOUT / [R4(1+RF / R52)] is obtained. Substitute VOUT = 5V, the fourth resistor is 1Ω, the variable resistor unit is 216KΩ, and the fifty-second resistor is 1KΩ into the formula to obtain I = 5 / [1×(1+216K / 1K)]≈0.023A=23mA. If the calculated current is the same as the preset grading current value of the third level, the grading verification is completed.

[0082] After the classification is completed, the PSE power supply equipment outputs the corresponding power according to the classification request, and the rated value of the output voltage is 50VDC. At this time, the processing module 100 controls the variable resistance unit and selects the corresponding resistance value to check whether the actual output power of the PS power supply equipment meets the standard. Continuing with the above-mentioned third-level classification verification example, to verify whether the PSE power supply equipment correctly outputs the third-level 13W power, it is only necessary to check the current I and the input voltage U. Specifically, I = W / U = 13W / 50V = 0.26A, so an electronic load with a current of 0.26A is provided in the power test. According to the formula I=VOUT / [R4×(1+RF / R52), substitute VOUT=5V, the fourth resistor takes the value of 1Ω, the variable resistor unit takes the value of 18.2KΩ, and the fifty-second resistor takes the value of 1KΩ into the formula to obtain I=5 / [1×(1+18.2K / 1K)]≈0.26A, and then check whether the port input voltage is 50V, W=I×U=0.26×50V=13W, which is the same as the preset third level output power, and the verification is completed.

[0083] The present application provides a test method for a POE system, which is implemented by a test device. The test method includes: steps S100 to S400.

[0084] S100, the processing module 100 collects the potential of the port voltage detection module 200, and determines whether the port voltage of the PSE power supply device is greater than the preset voltage according to the potential of the port voltage detection module 200; if so, the POE system is a non-standard system;

[0085] S200, the characteristic impedance verification circuit 310 outputs an indication signal to the PSE power supply device, and the indication signal is used for the PSE power supply device to respond and determine whether the characteristic impedance verification circuit 310 has a characteristic resistance; if it has a characteristic resistance, a hierarchical verification is performed;

[0086] S300, the load variable circuit 320 receives the classification check signal and generates an identification signal according to the classification check signal; the processing module 100 receives the identification signal and responds to control the load variable circuit 320 to adjust the load; the load variable circuit 320 outputs a classification current signal to the PSE power supply device;

[0087] S400, the processing module 100 receives the power signal and responds, controls the load variable circuit 320 to adjust the load, the power signal is output by the PSE power supply device according to the grading current signal; the processing module 100 calculates the current value flowing through the load variable circuit 320, and compares it with the preset grading current value. If they are the same, the grading verification is completed.

[0088] In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0089] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0090] In addition, various aspects or features of the present application can be implemented as methods, devices or products using standard programming and / or engineering techniques. The term "product" used in this application covers computer programs that can be accessed from any computer-readable device, carrier or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks or tapes, etc.), optical disks (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards and flash memory devices (e.g., erasable programmable read-only memory (EPROM), cards, sticks or key drives, etc.). In addition, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing and / or carrying instructions and / or data.

[0091] It should also be understood that in the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0092] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0093] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0094] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described below are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0095] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0096] The above are only preferred embodiments of the present application, and do not constitute any formal limitation on the present application. Any technician familiar with the art can use the above disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment of equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the present application without departing from the content of the technical solution of the present application should be included in the protection scope of the present application.

Claims

1. A test device for a POE system, connected to a port of a PSE power supply device, characterized in that: The test device comprises: a processing module, a port voltage detection module and a PSE test module; The port voltage detection module is connected to the processing module and the port of the PSE power supply device; The processing module collects the potential of the port voltage detection module, and determines whether the port voltage of the PSE power supply device is greater than a preset voltage according to the potential of the port voltage detection module; if so, the POE system is a non-standard system; The PSE test module includes: a characteristic impedance test circuit and a load variable circuit, wherein the characteristic impedance test circuit is connected to the port of the PSE power supply device, one end of the load variable circuit is connected to the characteristic impedance test circuit, and the other end of the load variable circuit is connected to the processing module; The characteristic impedance verification circuit outputs an indication signal to the PSE power supply device, and the indication signal is used for the PSE power supply device to respond and determine whether the characteristic impedance verification circuit has a characteristic resistance; if it has a characteristic resistance, a hierarchical verification is performed; The load variable circuit receives the classification inspection signal and generates an identification signal according to the classification inspection signal; the processing module receives the identification signal and responds to control the load variable circuit to adjust the load; the load variable circuit outputs the classification current signal to the PSE power supply device; The processing module receives a power signal and responds to control the load variable circuit to adjust the load. The power signal is output by the PSE power supply device according to the grading current signal. The processing module calculates the current value flowing through the load variable circuit and compares it with the preset grading current value. If they are the same, the grading verification is completed.

2. The test device of the POE system according to claim 1, characterized in that: The port voltage detection module includes: a plurality of parallel detection circuits, wherein a first end of the detection circuit is connected to a pin of a port of the PSE power supply device, a second end of the detection circuit is connected to a reference voltage, a third end of the detection circuit is connected to the processing module, and the third end of the detection circuit is used for the processing module to collect the potential of the detection circuit.

3. The test device of the POE system according to claim 2, characterized in that: The detection circuit includes: a first voltage-dividing resistor, a second voltage-dividing resistor and a collection node, the first end of the first voltage-dividing resistor is connected to the reference voltage and the other detection circuit, the second end of the first voltage-dividing resistor is connected to the collection node, the collection node is connected to the processing module, the first end of the second voltage-dividing resistor is connected to the collection node, and the second end of the second voltage-dividing resistor is connected to the port of the PSE power supply device.

4. The test device of the POE system according to claim 1, characterized in that: The characteristic impedance verification circuit includes: a first switch circuit, a second switch circuit, a unidirectional circuit, a characteristic resistance circuit, a first cutoff circuit and a second cutoff circuit, wherein the first end of the first switch circuit and the first end of the second switch circuit are commonly connected to the second end of the unidirectional circuit, the second end of the first switch circuit and the second end of the second switch circuit are respectively connected to the port of the PSE power supply equipment, the first end of the characteristic resistance circuit is connected to the first end of the unidirectional circuit, the first end of the first cutoff circuit and the first end of the second cutoff circuit are commonly connected to the second end of the characteristic resistance circuit, the second end of the first cutoff circuit is connected to the second end of the first switch circuit, the second end of the second cutoff circuit is connected to the second end of the second switch circuit, and the first end of the characteristic resistance circuit is connected to the load variable circuit.

5. The test device of the POE system according to claim 4, characterized in that: The first switch circuit includes: a seventh transistor and a thirteenth transistor, the collector of the seventh transistor is connected to the first pin of the port of the PSE power supply device, the emitter of the seventh transistor is connected to the second end of the unidirectional circuit, the base of the seventh transistor is connected to the first cut-off circuit, the collector of the thirteenth transistor is connected to the second pin of the port of the PSE power supply device, the emitter of the thirteenth transistor is connected to the second end of the unidirectional circuit, and the base of the thirteenth transistor is connected to the first cut-off circuit; The second cutoff circuit includes: a ninth diode and a tenth diode, the anode of the ninth diode and the anode of the tenth diode are connected to the second end of the characteristic resistance circuit, the cathode of the ninth diode and the cathode of the tenth diode are connected to the second switch circuit respectively, the cathode of the ninth diode is connected to the sixth pin of the port of the PSE power supply equipment, and the cathode of the tenth diode is connected to the third pin of the port of the PSE power supply equipment.

6. The test device of the POE system according to claim 4, characterized in that: The second switch circuit includes: the eleventh transistor and the twelfth transistor, the collector of the eleventh transistor is connected to the third pin of the port of the PSE power supply device, the emitter of the eleventh transistor is connected to the second end of the unidirectional circuit, the base of the eleventh transistor is connected to the second cut-off circuit, the collector of the twelfth transistor is connected to the sixth pin of the port of the PSE power supply device, the emitter of the twelfth transistor is connected to the second end of the unidirectional circuit; the base of the twelfth transistor is connected to the second cut-off circuit; The first cutoff circuit includes: a first diode and an eighth diode, the anode of the first diode and the anode of the eighth diode are connected to the second end of the characteristic resistance circuit, the cathode of the first diode is connected to the second pin of the port of the PSE power supply equipment, and the cathode of the eighth diode is connected to the first pin of the port of the PSE power supply equipment.

7. The test device of the POE system according to claim 4, characterized in that: The characteristic resistance circuit includes: a sixth resistor and a seventh resistor, the first end of the sixth resistor is connected to the first end of the unidirectional circuit, the first end of the seventh resistor is connected to the second end of the sixth resistor, the second end of the seventh resistor is connected to the first end of the first cutoff circuit and the first end of the second cutoff circuit, the first end of the load variable circuit is connected to the first end of the sixth resistor, and the second end of the load variable circuit is connected to the first end of the seventh resistor.

8. The test device of the POE system according to claim 4, characterized in that: The variable load circuit includes: an identification circuit, an electronic load circuit and a third switch circuit. The first end of the identification circuit is connected to the processing module and the first end of the electronic load circuit respectively, the second end of the identification circuit and the second end of the electronic load circuit are connected to the characteristic resistance circuit respectively, and the third switch circuit is connected between the processing module and the electronic load circuit.

9. The test device of the POE system according to claim 8, characterized in that: The identification circuit includes: a fourth operational amplifier, wherein the fourth operational amplifier non-inverting input terminal is connected to the characteristic resistance circuit, the fourth operational amplifier inverting input terminal is connected to the reference voltage, and the fourth operational amplifier output terminal is respectively connected to the processing module and the first terminal of the electronic load circuit.

10. A method for testing a POE system, implemented by the testing device according to claim 1, characterized in that: The test method includes: The processing module collects the potential of the port voltage detection module, and determines whether the port voltage of the PSE power supply device is greater than a preset voltage according to the potential of the port voltage detection module; if so, the POE system is a non-standard system; The characteristic impedance verification circuit outputs an indication signal to the PSE power supply device, and the indication signal is used for the PSE power supply device to respond and determine whether the characteristic impedance verification circuit has a characteristic resistance; if it has a characteristic resistance, a hierarchical verification is performed; The load variable circuit receives the classification inspection signal and generates an identification signal according to the classification inspection signal; the processing module receives the identification signal and responds to control the load variable circuit to adjust the load; the load variable circuit outputs the classification current signal to the PSE power supply device; The processing module receives a power signal and responds to control the load variable circuit to adjust the load. The power signal is output by the PSE power supply device according to the grading current signal. The processing module calculates the current value flowing through the load variable circuit and compares it with the preset grading current value. If they are the same, the grading verification is completed.

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