Special Magnetically Assisted Electric Contact Pressure Gauges are developed based on standard magnetically assisted electric contact pressure gauges to meet different operating requirements. The product range includes various models featuring vibration resistance, corrosion resistance, suitability for ammonia applications, combined corrosion and vibration resistance, and diaphragm seal isolators.
Accuracy Class: 1.6.
Measurement Range: 0–0.1 to 0–60 MPa, -0.1–0, -0.1–2.4 MPa.

Magnetically Assisted Electric Contact Pressure Gauges are widely used in petroleum, chemical processing, metallurgy, electric power, machinery, and other industrial sectors, as well as in electromechanical equipment, to measure the pressure of various fluid media without explosion hazards.

When used with appropriate electrical devices (such as relays and frequency converters),

these instruments enable automatic control and signaling (alarms) for the measured or controlled pressure system.

Structure and Working Principle

The Electric Contact Pressure Gauge consists of a measuring system, indicating system, magnetically assisted electrical contact device, housing, adjustment mechanism, and junction box (connector socket).

The working principle of the Electric Contact Pressure Gauge is based on the Bourdon tube in the measuring system. Under the pressure of the measured medium, the free end of the Bourdon tube undergoes corresponding elastic deformation and displacement. This displacement is transmitted and amplified through a connecting rod and gear transmission mechanism, causing the pointer (together with its contact) mounted on the gear to indicate the measured pressure value on the dial. At the same time, when the moving contact touches the contact on the preset pointer (upper or lower limit), the control circuit is opened or closed, thereby achieving automatic control and alarm signaling.

Technical Specifications

Dial Scale Range and Accuracy Class

Note: Accuracy classes shown in parentheses are available for special orders only.

Mounting Methods:

1 · Axial Mounting with Front Flange

2 · Radial Mounting without Flange

3 · Radial Mounting with Front Flange

Electrical Contact Specifications

Operating Voltage (Maximum): 380V AC; 220V DC

Maximum Operating Current: 1A

Continuous Current: 0.6A

Maximum Power: 30W

Operating Temperature of Electric Contact Pressure Gauge: -25°C to 55°C

Upper Operating Pressure Limit: No More Than 2/3 of the Instrument's Upper Range Limit

Operating Environment: Vibration Frequency Not Exceeding 25Hz and Amplitude Not Exceeding 0.5mm

Product Types

This series of instruments features an innovative design, reliable construction, a comprehensive range of models and specifications, stable operation, and strong adaptability. It also combines measurement and control functions with simple installation and low maintenance requirements. These advantages make it a pressure measurement and control instrument that offers significant benefits over conventional pressure controllers without indication, adjustable switching differential, or external setting devices.

To meet different application requirements, such as vibration resistance, corrosion resistance, and explosion protection, suitable vibration-resistant, corrosion-resistant, or explosion-proof electric contact pressure gauges can be selected.

Standard Type: Suitable for measuring the pressure of gases and liquids that are non-corrosive to copper alloys and iron.

Corrosion-Resistant Type: The main pressure-sensing components and instrument housing are made of stainless steel, making it suitable for measuring the pressure of highly corrosive gases and liquids.

Vibration-Resistant Type: The gauge housing is filled with oil to provide liquid damping, ensuring stable pointer indication. It is suitable for applications involving strong pressure pulsations or significant environmental vibrations.

Explosion-Proof Type: Suitable for hazardous locations where explosive mixtures may be present.

Electrical Working Principle

Taking compressor motor control as an example: The compressor automatically starts when the air receiver pressure reaches the lower limit and stops when the pressure reaches the upper limit.

The control process is as follows: When the pressure reaches the lower limit (or is below the lower limit at startup), the moving contact (common power terminal) of the Electric Contact Pressure Gauge connects with the lower limit contact. Relay J1 is energized and self-latches, and its normally open contact closes to activate J3, supplying power to the motor. When the pressure reaches the upper limit, the moving contact connects with the upper limit contact, energizing relay J2. Its normally closed contact opens, cutting off the power supply to J1. The normally open contact of J1 then opens, causing J3 to release and the motor to stop. This cycle repeats to achieve automatic control.

Wetted Materials

The Electric Contact Pressure Gauge is made of 304 stainless steel or 316 stainless steel.