Version 2.02 15.05.2007 Function of VS 3000
20
3.18 Compressor monitoring
The controller is equipped with the following monitoring functions as well as control and regulating functions:
S Motor overload cutout
S Low oil pressure cutout
S Compressor cylinder head temperature
S High pressure
S Low pressure
S Compressor starts
3.19 Safety loop
So as to provide redundancy of the monitoring system, provisions are made in addition to the VS 3000 monitor-
ing functions for all or individual compressors of a pack to be disabled in critical operating situations.
Due to the type of wiring in the system the control contacts used for this purpose are prioritized in descending
order as follows:
Disabling of all compressors
1. Safety high-pressure cutout
2. High-pressure cutout
3. If installed: Discharge gas defrosting high-pressure cutout (Z2, Z2R and Z1)
4. LP cutout
Disabling of compressors respectively affected
5. Low oil pressure cutout
6. Motor overload cutout
As a result of their arrangement in the safety loop, actuation of a high-priority safety contact (e.g. high-pressure
cutout) also de-energizes and thus activates all low-priority alarm contacts. So as to prevent the pack controller
from transmitting all secondary alarms, the transmission of low-priority alarm signals is blocked in the simulta-
neous occurrence of a higher-priority alarm event.
3.20 Monitoring of motor overload cutout
The compressor motor is monitored by the motor overload cutout. The auxiliary contact is open in the alarm state (no
signal at controller input). The compressor is stopped directly and disabled for all further control actions when the
motor overload cutout is actuated. On resetting the motor overload cutout, the compressor can be enabled either auto-
matically or manually.
Compressor enabling mode following actuation of a motor overload cutout is defined by the Mot.cutout C parameter
(Menu 3-1). When Mot.cutout C Y is entered, the compressor is stopped on actuation of the motor overload cutout and
remains disabled. It then needs to be enabled manually (Menu 3-1-c Enable comp.stages).
The fault report generated on actuation of the motor overload cutout is not logged off until the cutout has been reset
and the compressor has been enabled manually. When Mot.cutout C N is entered, the compressor is stopped on
actuation of the motor overload cutout. After resetting the cutout, the compressor will be loaded again automatically as
and when refrigeration is demanded. The default setting is Mot.cutout C Y.
To Next Page
Loading...
Need help?
General
