In this section we will read about
- I/P Converter (Current to pressure Converter)
- Valve positioner
- Parts of a pneumatic control valve positioner
- Control Valve and its types
- Solenoid Valve
- Pneumatic Cylinder
- Butterfly Valve
- Pneumatic Globe Valve
- Work of different Parts of a Control Valve
- Pneumatic globe valve types
- Characteristics of Control Valve
- Class of a control valve
- Pressure Transmitter
- Working principle of pressure transmitter
- Pin type pressure Transmitter
- Connections of a pressure transmitter
- How signal is checked in a pressure transmitter
How to check Pressure Switch
In this Section, We will study the connections of a Pressure switch and how to check a pressure switch.
pressure switch as the name indicates is a switch works on Pressure increase or decrease.
Connection of a Pressure Switch
- 3 wires are there in a Pressure switch
- 2 wires are connected in a pressure switch
- One is connected in common and the other is connected in NO or NC according to the application.
NC means Normally Closed.
and NO means Normally Open.
NC & NO are two contacts.
How to check a pressure switch
- Step 1: first we check the continuity between common between normally closed (NC). For this one knob of a multimeter is kept at common contact and the other knob is kept at NC Contact. It must show continuity.
- Step 2: Now after increasing the pressure when pressure is equal to set pressure we check the continuity between common and normally open (NO). For this one knob of a multimeter is kept at common contact and the other knob is kept at NO Contact. It must show continuity.
- Step 3: now we will decrease the pressure and when decreasing pressure is equal to the set pressure again continuity between common and normally closed (NC).
From the above points, it is clear that pressure Switch works as a switch works on increasing and decreasing the pressure. By this application, Pressure switch may be used to either trip or start a motor or any process equipment. Pressure Switches are widely used in steam turbines since we need to trip the turbine at various parameters for safety. In steam turbines or in any Process various process pumps are started and tripped at various pressure settings. It is concluded from the above discussion that if any process needs to start or trip at various pressure, a pressure switch is used.