Differential pressure switch fault diagnosis and maintenance skills

A differential pressure switch is a switching device capable of detecting the difference in pressure between two points. Usually it consists of a sensor, a control circuit and an output device. It measures the pressure difference and compares it with a preset threshold to achieve corresponding switch control.

Differential pressure switches are widely used in many fields, including industrial production, environmental monitoring and automation control. Its principle is to use a differential pressure sensor to measure the pressure difference between two points. These sensors contain two pressure sensors and a differential pressure unit, which measure the pressure difference by measuring the pressure at two points and calculating the difference.

The control circuit is the core part of the differential pressure switch and is used to process the signal output by the sensor and compare it with the preset threshold. Once the pressure difference exceeds a set threshold, the control circuit triggers the operation of the switch.

The output device is usually an electromagnetic relay or a transistor, etc., which is used to convert the signal of the control circuit into actual switching behavior. This allows the on/off status of other devices to be controlled as needed.

Differential pressure switches have many important applications in different fields:

1. Fluid flow control: By measuring the pressure difference, differential pressure switches can achieve precise flow control of fluids, such as in liquid pipeline systems, water supply systems and chemical processes.

2. Filter clogging monitoring: It can be used to monitor whether the filter is clogged. When the accumulation of impurities causes the filter to clog, the differential pressure increases, and the differential pressure switch can detect and trigger corresponding alarms or maintenance operations to improve system reliability.

3. Air flow control: Differential pressure switches are widely used in air conditioning and ventilation systems to achieve precise air flow control by measuring the pressure difference between inlets and outlets, improving indoor environmental comfort and energy efficiency.

4. Liquid level control: It can also be used for liquid level control, by measuring the pressure difference of the liquid at different locations to infer the liquid level height or depth, and is used in fields such as water treatment, oil tanks and storage tanks.

Overall, differential pressure switches play a key role in multiple application areas, providing precise pressure difference measurement and control, helping to improve production efficiency, system reliability and energy efficiency.