Liebert TM-10098 iCOM Controls Training and Service Manual, compressor operation Switch 2nd

iCOM Controls Training and Service Manual

Optional Dual Compressor Digital Scroll Operation

100	1 compressor operation Switch 2nd
70			compressor ON
50				2 compressor operation
PWM 35
20		Switch 1st compressor ON

			Off
			On		C2
			C1
Start/ stop
		Off				On
0%	10		20	25	35		70

In the chart above we are defining the Digital Compressor start and stop at the capacity need and how the compressors load and unload with the PWM from the controller and the unit setting for temperature control.

Note that the Digital Scroll will run continuously while the head is raised and lowered as the need for cooling is required from 10% to 100% and vise versa.

Optional Glycool (Econ-O-Cycle) Cooling

When supplied with the Glycool option, the basic unit is supplied with an additional coil, piping, valve and a Glycol Fluid Sensor (AQ), which is mounted to the unit supply fluid line and serves as control interface in determining the system operation. Selection of the glycool or compressorized operation is controlled by microprocessor using this aquastat to sense the glycol temperature.

The Glycool (Econ-O-Cycle) Cooling program establishes two distinct control bands for cooling control operation. The first band controls the operation of the chilled glycol valve and the second controls the operation of the compressors, either 2-stage or 4-stage.

The microprocessor checks the return air temperature and the entering glycol fluid temperature to determine a cooling capacity. In order to reduce compressor cycling and to prevent chilled glycol valve hunting, Glycool (Econ-o-Cycle) cooling capacity does not become available until the entering chilled glycol fluid

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