What is a dual society? what is dual economy.
PS2 Dual Pressure Controls are designed for use on high and low pressure applications in refrigeration, air conditioning, and heat pump systems. This control react to changes in either low or high side pressures, providing single-device control of the compressor or other electrical device.
High-pressure controls can protect compressors and system components from dangerously high-pressure situations by shutting the compressor off at certain elevated pressures. Some high- and low-pressure controls have to be manually reset and some reset automatically.
Low-pressure controls can be used to: Directly control a case’s temperature by cycling a compressor on and off at the required coil temperatures; on medium-temperature equipment, this will also provide a means of defrosting the evaporator; Cycle a compressor on and off when used on a pump down system; and.
Adjust the low pressure range screw until the scale pointer indicates the desired cut-in. Turning the range screw clockwise lowers both the cut-in and the cut-out: counterclockwise raises both. 2. Adjust the differential screw until the scale pointer indicates the desired differential.
Dual-pressure controls are comprised of low pressure and high-pressure controls mounted in a single housing, with a single switch operated by either control. Other functions of mechanical pressure switches include condenser fan cycling and oil pressure safety control.
The low pressure switch monitors the refrigeration system for a loss of refrigerant charge, and may also be helpful in stopping the evaporator (indoor) coil from freezing up due to a dirty filter or low airflow over the coil. … low pressure charge. If either one of these switches trip, the HVAC unit will shut down.
What is true of a high-pressure control? It protects the compressor from high pressures. … A safety control (Boiler relief valve, or a pressure-regulating valve for system pressure), and an operating control (water regulating valve). 36.
The most common cause of a refrigerant high-pressure switch tripping in the wintertime is lack of airflow across the indoor coil. One of the signs of lack of airflow is a high temperature split across the indoor coil. … A dirty coil will prevent proper airflow and heat transfer across a coil.
The temperature of a refrigerated box can be controlled by a low-pressure control (LPC), instead of a thermostat, because of the pressure/temperature relationship in the refrigeration system.
- Inspect the terminals on the pressure switch. …
- Set the voltmeter or multimeter to display AC volts.
- Touch one of the probes from the meter to either one of the terminals on the pressure switch. …
- Check the voltage reading on the meter.
Pirani sensors are commonly used for measurements in the low vacuum range. These sensors rely on a heated wire with electrical resistance correlating to temperature.
A pressure switch is a device that operates an electrical contact when a preset fluid pressure is reached. The switch makes an electrical contact on either pressure rise or pressure fall from a certain preset pressure level. … A pressure transducer converts pressure into an electrical output signal.
a 30-50 switch turns on at 30lbs pressure and turns off at 50. and like wise the 40-60 turns the pump on at 40lbs and off at 60. If your pump only has a maximum head pressure of 50lbs the 40-60 will not work for you because the will not be able to reach 60lbs and the pump will never shout off.
To make adjustments to your low side, use a screwdriver to turn the spindle clockwise to lower the value and counterclockwise to raise the value. To make adjustments to your differential, turn the spindle clockwise to raise the value and counterclockwise to lower the value.