865D-HP

Three Phase Head Pressure Control

The 865D-HP low ambient three phase head pressure control monitors the head pressure by sensing excessive liquid sub cooling and modulates the condenser fan motor speed and varies the volume of air through the condenser. This application requires the controller be installed as a package with a continuously variable speed High Slip tolerant/ventilated (HS/V) three phase motor. For motors that cannot be operated in variable speed mode, the 865D-HP also offers a Fan Cycling control mode which simulates the variable speed mode. The 865D-HP can also be used as a Manual Adjust or Vdc/mA input three phase fan speed control. The 865D-HP is a direct replacement for the obsolete 865-3AA, 865D, and 865D-2 Series Controls.
Features
  • Onboard diagnostics to verify proper installation
  • LED indicators verify proper operation
  • Multiple voltages 208-230/460 VAC
  • NEMA-3R weatherproof
  • 1/2 to 2 H.P. Motors, 8 amps max
  • Monitor up to two liquid line temperature sensors (expandable up to 6 sensors with the addition of 851-MS Multiple Senor Selector)
  • Monitor one Vdc or mA pressure transducer
  • Can be used as a manual or Vdc/mA input three phase fan speed control
  • Fully adjustable LOW and HIGH set points
  • Detects three phase power faults
  • Can be used in Fan Cycling Mode for those motors which cannot be run in variable speed
Data Sheets
Stacks Image 1133

Why Measure Head Pressure using Temperature instead of Pressure?

Many people assume that the best way to control the head pressure from a compressor is to directly sense the line pressure using a sensor inserted into the liquid line.