14.01.2019
65/185
Disable all compressors
1. Safety high pressure cut-out
2. HP limiter
3. NP monitor
Disable relevant compressors
4. Compressor high pressure limiter
5. Compressor motor overload cut-out
Due to their arrangement in the safety chain, when a high priority safety contact (e.g. high pressure limiter) is
tripped, all lower priority alarm contacts are also deenergised and thus active. The sending of low priority alarm
signals at the same time when a higher priority alarm event occurs is locked so that all secondary alarms are
not sent by the pack controller in this case.
Monitoring of differential oil pressure switch / compressor high pressure limiter
The oil differential pressure, the high pressure at the pressure ports of every compressor, or both, can be
monitored via digital inputs with floating contacts.
Using the parameter
Text Oil/HP-F.
(menu 3-1), it is possible to select which type of pressure switches should
be monitored via these inputs. This parameter can be used to select the message text output when the signal
inputs for the oil differential switch / HP monitor for compressors 1-12 are activated:
1
Oil diff. pr. Cx
or
2
HP-Cutout Cx
or
3
Oil/HP-Fault Cx
The pressure switches are open in the alarm state. If the pressure switch trips, the compressor is switched off
immediately and disabled for the following control processes. If it is reset, the compressor is enabled.
Oil / HP switch alarm delay (only for refrigerant CO
2
)
The alarm signalling for the oil/HP switch can be delayed:
the requirements for this are:
•
The alarm input is enabled using the parameter
Oil pr. cutout = YES
•
An alarm delay
Del.Oil/HP-F.
greater than zero minutes is specified
•
The alarm priority is not "---"
Then in the event of an oil / HP fault of a compressor, an appropriate alarm with the preselected message
priority is not sent and registered in the message memory until after expiry of the delay time.
However, in order to ensure that any short-time compressor oil / HP fault is registered in the message list, a
temporary message (timestamps "come" and "go" simultaneously) with the priority "0" is initially registered
when any compressor HP fault is detected.
Monitoring of the compressor motor overload cut-out
The compressor motor is monitored by the motor overload cut-out. The auxiliary contact is open in the alarm
state (no signal at the input of the controller). If the motor overload cut-out trips, the compressor is switched off
immediately and disabled for the following control processes. The compressor can be enabled again
automatically or manually if the motor overload cut-out is reset. The type of compressor enable after tripping of
a motor overload cut-out is defined using the parameter
Motor protect.
(menu 3-1). With the entry of
Motor
protect.
Y
, the compressor is switched off and permanently disabled with the tripping of the motor overload cut-
out. A manual enable must be performed (menu 3-1-c
Enable comp.stages
).
If no oil differential pressure switch or HP limiter is used, the monitoring of the oil differential switch / HP
limiter for the compressor can be activated / deactivated using parameters.
Summary of Contents for VS 3015 C
Page 8: ...14 01 2019 8 185...
Page 46: ...14 01 2019 46 185...
