KGL Operating Manual – VS 3010 BS
2018-07-02
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This value must not be set too low. If the value is too low, the cascade controller may no longer be
able to reach the specified temperature setpoint.
4.6.1.10 Fixed opening degree for service purposes
For service purposes, a fixed opening degree can be specified as an alternative to the automatic setting of the
opening degree via the regulation functions. A message “OD manual” is registered in the log memory and
forwarded if necessary. The message priority can be parametrised.
In this case, the superheat controller is not active. Consequently, there is a danger of overfilling the
heat exchanger!
4.6.1.11 Emergency Op.
In the event of failure of the temperature measurement or the superheat control, cooling continues to operate
using an emergency opening degree. This emergency opening degree is calculated from the average value for
the opening degree over the last day (24 hours) and with an upper limit set by an adjustable parameter
(parameter Not-Öffnungsgrad, menu 3-2-3). The parameter emerg.c-o OD also engages when it has not been
possible to calculate a 24 hour value for the opening degree, for example following a first start.
Failure of the temperature control:
If both sensors for the temperature control fail (HP-Z2 and R4.1), regulation continues using the emergency
opening degree. The superheat controller remains active and can impose an upper limit on the emergency
opening degree. In the event of the failure of one of the two sensors, regulation continues using the remaining
sensor without switching to emergency operation.
Failure of the superheat control:
If superheat control fails (failure of LP/to-Z1 and R5.1 or failure of R6.1), emergency operation is switched to
and the emergency opening degree is output. The temperature controller remains active and can impose an
upper limit on the emergency opening degree.
Failure of temperature control and superheat control:
The emergency opening degree is output.
4.6.1.12 Manual Shutdown
A voltage present at the "fast unload/ external OFF" 230 V digital input of the pack controller switches off all
control functions (pack regulation and cascade regulation). Manual shutdown can be activated via digital input
16 (terminals 80/81). However all interfaces and operating functions remain active.
The controller and connected voltage carrying components remain supplied with power!
4.6.1.13 Cascade disabling refrigeration points
Cascade regulation is disabled if disabling refrigeration points is active in the Z1 circuit (for function /criteria
see chapter
). The cooling via the cascade is interrupted for as long
Disabling of refrigeration points, page 75
as the disabling of refrigeration points is active.
