Meter Pen Box Circuit for Low-Resistance High-Current Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional multimeters face issues with high loop resistance during high current measurements, leading to heat generation and potential product deformation or damage due to spatial limitations, which are not effectively addressed.
Innovation Solution
The electronic measuring instrument incorporates a meter pen box with copper-embedded inserts and metal elastic pieces in the terminals, forming a loop with the meter to reduce resistance and includes a logic circuit for determining proper connection, along with a micro-control unit for mode detection and alert messages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conventional multimeter with universal test probe is used for high current measurement, then the device can perform standard measurements with universal format, but the loop resistance cannot be reduced effectively leading to heat generation and potential product damage
Solution Approach 1:
The invention divides the measurement system into two separate components: a conventional multimeter for control and display functions, and a dedicated meter pen box for high current measurement. This segmentation allows the meter pen box to have optimized low-resistance terminals and copper-embedded inserts specifically designed for high current paths, while the multimeter maintains its universal measurement capabilities. The separation enables each component to be optimized for its specific function without compromise.
Solution Approach 2:
The meter pen box acts as an intermediary device between the test probes and the multimeter. It contains the high current measurement circuitry with optimized low-resistance connections, copper-embedded inserts, and metal elastic pieces that facilitate better current flow. This intermediary structure reduces the overall loop resistance while allowing the multimeter to continue using its universal test probe interface.
2Ease of operation
If the multimeter is designed with small handheld form factor, then the device is portable and easy to operate, but the spatial limitation prevents effective reduction of loop resistance for high current measurement
Solution Approach 1:
By separating the high current measurement function into a dedicated meter pen box, the invention allows the main multimeter to remain compact and portable. The meter pen box can be designed with optimized internal space for low-resistance connections without compromising the portability of the main device. Users can attach the meter pen box only when high current measurement is needed.
Solution Approach 2:
The invention extends the measurement capability to another dimension by adding the meter pen box as an external attachment. This allows the system to achieve low loop resistance through the optimized structure of the meter pen box while the multimeter maintains its compact handheld form factor. The solution moves from trying to fit everything in one device to using a modular approach where the high current path is optimized in the attached pen box.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces loop resistance, preventing heat buildup and potential damage, while ensuring safe and accurate high current measurements up to 30A, maintaining compliance with safety regulations.
Implementation Method 1
forming a loop with the meter to reduce resistance
Implementation Method 2
copper-embedded inserts and metal elastic pieces in the terminals
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An electronic measuring instrument comprises: an electric meter (1) equipped with a first to fourth holes (11, 12, 13, 14) and a logic circuit, and a meter pen box (2) comprising a circuit board. One end of the meter pen box (2) is equipped with a first to fourth terminals (21, 22, 23, 24). Another end of the meter pen box (2) is equipped with a pair of test probes (25, 26). The first to fourth terminals (21, 22, 23, 24) are correspondingly plugged into the first to fourth holes (11, 12, 13, 14). The circuit board is coupled to the third terminal (23), the fourth terminal (24) and the pair of test probes (25, 26). A metal elastic piece (211) is included in each one of the first terminal (21) and the second terminal (22). A loop between the first hole (11) and the second hole (12) is formed through the meter pen box (2) when the first terminal (21) and the second terminal (22) are plugged into the first hole (11) and the second hole (12) respectively for determining whether the electric meter (1) is plugged with the meter pen box (2) through the logic circuit.