Hoffman Controls 880-35 Head Pressure Control

Product Description

Hoffman Controls - 880-35 The 880-35 Low Ambient Head Pressure Control is designed to modulate energy efficient Electrically Commutated condenser fan Motors (ECM) in air conditioning and refrigration systems. The 880-35 control varies the speed of the condenser fan ECM motor(s) to vary the air volume through the condenser consequently regulating head pressure for proper heat rejection in low ambient temperatures. The 880-35 Head Pressure Control monitors the head pressure by sensing the sub-cooled liquid line temperature by placing a 10K sensor on the refrigerant liquid line. As the liquid line temperature drops, the motor speed will be reduced to prevent freezing of the coil. As minimum motor speed is reached, the control will cycle the motor off until the liquid line coil temperature has returned to safe operating levels. At this point, the motor will modulate back to full speed to maintain proper heat rejection. The 880-35 control provides an adjustable LOW SET point of 40°F to 80°F and an adjustable HIGH SET point of 60°F to 140°F for the ability to custom tune the control for any application.

• Not refrigerant specific Class II Controller, conformal coated.
• One or up to two liquid line temperature sensor inputs with the hottest sensor controlling operation.
• Removing sensors from the sensor inputs will Self-Test ECM motor full speed operation.
• Temperature input Low Set Point range 40°F to 80°F and High Set Point range 60°F to 140°F in 1°F increments.
• ECM motor drive options include an adjustable 13-17VDC peak/80Hz PWM signal, selectable 0-10VDC or 10-0VDC (fail safe) signals.
• 20ma ECM motor drive capability (typically two motors).
• 2.5 second full speed Hard Start.
• 24Vac activated selectable Direct or Reverse acting Heat Pump mode.
• Operating Ambient -31°F to +160°F, Humidity 95%, Noncondensing, Dimensions 3.6L x 4.25W x 1.5H, Power supply 22-30VAC, 1VA.