How should a pressure switch be set?
Armstrong booster systems are designed so that the pressure switches can be set or reset in the field. There are a few tricks to setting a pressure switch. One is isolating the switch using the valve arrangements on the sensing line. The other is making sure you dont let the differential on the switch fool you. In order to accurately set a pressure switch, you would begin by trapping pressure in the sensing line. The following procedure is an example of how to get an accurate low system pressure alarm set: • Run a pump to pressurize the sensing line • Close the isolation valve on the sensing line at the discharge header • Turn off the pump. You have now trapped discharge pressure in the sensing line, and can read this pressure off the package mounted pressure gauge. • You can then bleed off pressure by opening the isolation valve on the sensing line to attain the desired pressure for the pressure switch setting To actually set the switch, it is important to remember that the set point
