Offtime Defrost; Sensor Applications; Suction Pressure Sensor; Important - Hussmann Proto-Aire EZ Manual Del Usuario

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Offtime Defrost

Application
Off-time defrost is the simplest defrost type. A relay is used to de-energize a solenoid valve at
specific times. Suction stop solenoid valves should be used to control temperature on long lineups
due to the limited receiver capacity. Isolation ball valves for each case lineup are recommended
for ease of servicing.
Defrost Operation
1. To initiate a defrost, the control board will de-energize the specific circuit solenoid.
2. After the preset time for defrost has elapsed, the unit will energize the solenoid allowing
normal refrigeration.

Sensor Applications

Suction Pressure Sensor

This suction pressure input provides the electronic controller the necessary information to
cycle the compressors on and off to maintain an overall setpoint.
The current draw required by analog meters (Volt-Ohm Meters or VOMs) can permanently
damage electronic equipment.
Never use a VOM to check computer components or computer controlled systems. Use a
Digital Multi-meter (DMM) to measure voltage, amperage, milliamperes, or ohms. If a range is
exceeded, the display will show OL (overload).
3090249_D
P/N

IMPORTANT

Proto-Aire EZ I/O Manual