McQuay PFS 155C, Руководство по эксплуатации и обслуживанию

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OM 135 PFS 155C - 315C 19
Digital Output Board
The Output Board contains up to 24 solid state relays which are used to control the compressor,
cooling tower fans, solenoid valves and alarm annunciation. It receives control signals from the
Microprocessor Control Board through a 50 conductor ribbon cable.
Figure 3, Digital output board
Analog / Digital Input Board (ADI)
The ADI Board provides low voltage power for the temperature and pressure sensors. It also
provides optical isolation between the Microprocessor Control Board and all 24V switch inputs.
LED's are furnished on the board to give a visual indication of the status of all digital inputs. All
analog and digital signals from sensors, transducers and switches are received by the ADI Board and
then sent to the Microprocessor Control Board for interpretation.
Figure 4, ADI board