861-ASQ

Condenser Fan Sequencer

The 861-ASQ Series Sequencer is a direct-acting electronic step controller used to control multiple condenser fan motors in incremental, sequential steps for low ambient control of air-cooled condensers.
Features
  • Liquid line sensing
  • Multiple input/output functions
  • Adjustable staging
  • LED stage indicators
  • Momentary loss of power protected
  • Accepts input from 851-MS Multi-Sensor Selector
  • Output for 816-DH(DC) Head Pressure Controller
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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.