Hydraulic control circuit with locking function

Abstract

The invention discloses a hydraulic control circuit with the locking function, and relates to the technical field of liquid level control circuits. The circuit is composed of a liquid level detecting module, an isolation module and a liquid level state locking module. The hydraulic control circuit is characterized in that the liquid level detecting module is used for judging the liquid level by comparing the liquid level relation between a reference liquid level electrode and a high liquid level electrode and a low liquid level electrode; the isolation module transmits a liquid level signal detected by the liquid level detecting module to an internal logic locking circuit safely through the isolation bridge technology; the liquid level state locking module locks the liquid level signal detected by the liquid level detecting module through a specific adjustable combined logic circuit until the next state is changed. An input primary power source and an internal secondary power source can be effectively isolated through an isolation bridge module, the safety of an internal circuit is effectively protected, relay node output is adopted in the liquid level locking module, the liquid level locking module is completely isolated from a circuit of a controlled device again, and the safety of the controlled device can be effectively protected.

Description

technical field [0001] The invention relates to the technical field of control circuits, in particular to a circuit for controlling the liquid level in a boiler measuring cylinder, in particular to a liquid level control circuit with lock, which is used for the liquid level control voice alarm circuit control. Background technique [0002] At present, a large number of low-pressure small boilers with a nominal pressure of 2.5MPa and an evaporation capacity of less than 10T in the society mostly use the traditional glass tube (plate) water level gauge, which does not have the alarm and control function of water level exceeding the limit. With the implementation of relevant national laws and regulations, these boilers without water level overrun alarm and control functions have been banned from production and use, and replaced by boilers with simple structure, less maintenance-free steam water level overrun alarm controller. The current liquid level detection methods include ...

AI Technical Summary

Problems solved by technology

But there are also four defects: 1. There is no circuit protection, which brings potential unsafe factors, especially when the wiring is wrong or the electrodes are short-circuited, it is easy to short-circuit itself, and leakage may occur, so that the device under test is electrified, causing unnecessary Loss

2. The system design lacks anti-shake treatment. When the electrode is close to the water surface or when the water surface fluctuates, the output signal will also follow the jitter, which will easily cause frequent switching of the motor and affect the life of the motor.

3. The circuit function is single, there is no alarm device, and multiple protections cannot be implemented, which greatly reduces the safety factor

4. High temperature is easy to generate scale, and the electrode is also prone to polarization and corrosion, which affects the conductivity of the electrode. There are certain safety hazards and frequent maintenance is required.

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