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.