3.21 Compressor Functions - group 28
3.21.1 28-2* Discharge Temperature Monitor
The Discharge Temperature Monitor (DTM) can be used to prevent the discharge temperature from reaching dangerous levels.
Two temperature levels of increasing severity can be programmed. These levels are called warning level (set in par. 28-24 Warning level) and emergency
level (set in par. 28-26 Emergency level) in order of increasing severity. Each level corresponds to a particular set of preventive actions.
Discharge temperatures above the Emergency level cause an alarm and an immediate trip to prevent damage to the compressor.
Normal operations apply for discharge temperatures below Warning level. The discharge temperature is passively monitored without affecting drive
operations.
Discharge temperatures in the range from Warning level to Emergency level trigger a warning and an action set by parameter par. 28-25 Warning Action.
The action can be None or Decrease cooling. If the action is set to Decrease cooling the cooling is decreased as a preventive action in an attempt to
lower the discharge temperature.
Cooling is decreased by step-wise lowering of the shaft speed until the discharge temperature either drops below Warning level or exceeds Emergency
level. Each step represents a three minute period during which the maximum allowed shaft speed is 10 Hz lower than the previous step. The initial step
occurs when the discharge temperature rises from below to above Warning level and uses the current shaft speed as basis for the 10 Hz speed reduction.
The speed steps enforce maximum shaft speeds. If the reference corresponds to a lesser speed, the reference is obeyed. If it corresponds to a higher
speed, the speed is limited to the maximum shaft speed for that step.
3 Parameter Description
ADAP-KOOL
®
Drive Programming Guide
218
MG.11.N1.02 - VLT
®
is a registered Danfoss trademark
3
Содержание ADAP-KOOL Drive
Страница 14: ...2 How to Programme ADAP KOOL Drive Programming Guide 14 MG 11 N1 02 VLT is a registered Danfoss trademark 2...
Страница 201: ...ADAP KOOL Drive Programming Guide 3 Parameter Description MG 11 N1 02 VLT is a registered Danfoss trademark 201 3...
Страница 222: ...4 Parameter Lists ADAP KOOL Drive Programming Guide 222 MG 11 N1 02 VLT is a registered Danfoss trademark 4...