here. This suppression does not apply to sensor error alarm or, if activated, external alarms. If
range alarm is selected, this parameter is ineffective.
A33: Operating time before time depending load replacement
Load replacement depending on time is mainly used in the field of refrigeration technology to
balance the use of the connected compressors. If only some of the outputs are continuously active,
outputs that have not yet been activated will be used.
This parameter determines the time to elapse before outputs are changed for the first time. If there
are multiple bypass groups defined with parameter A44 the load replacement affects entire groups.
A34: Operating time range
If operating mode with time-dependent load replacement is activated these time ranges are
available for parameter A33.
A35: Measuring input
This parameter selects either temperature or pressure measuring. Deactivated sensors can be
disconnected; their measuring input causes no error message. Note the selection of the display
value with parameter A15. Measured and indicated value must not be the same. It is possible to
indicate a temperature value calculated by a pressure value or to indicate a pressure value
calculated by a temperature value.
A36: Temperature scale
Indication can be switched between Fahrenheit and Celsius. At conversion, the parameters and
setpoints maintain their numerical value and adjustment range
A37: Refrigerant
Selection of the used refrigerant in the plant.
A38: Indication value for lower value at pressure measuring
A39: Indication value for upper value at pressure measuring
If pressure measuring is selected with parameter A35 these parameters allow scaling of the
measuring input. The value to be indicated for the lower and upper measuring value then defines
the range the controller will indicate.
A40: Activation of time-dependent load replacement
This parameter either activates or deactivates time-dependent load replacement to balance the
use of the connected compressors. The replacement takes place after the operating time set with
parameter A33.
A41: Sequential operation mode
This parameter either activates or deactivates the sequential operation mode. If this mode is
activated different compressors or bypass-groups will be activated or deactivated (if possible) at
each change of output stage to ensure an even load of the compressors.
Concerning the switching of the compressors or bypass-groups the following applies:
If several compressors or bypass-groups are activated the first started unit will be deactivated first.
If several units are deactivated the first stopped unit will be activated first.
If in sequential operation mode the connections of the units to the respective output stage is
ineffective. The control prevents the switching of valves if the compressor has not started and
assures the simultaneous switch-off of valves when the compressor is switched off. The minimum
action times (parameters A21-A25) concerning valves will be adjusted to the times of the
respective compressors.
A42: Interlocking of total operating times
This parameter releases the locking of the total operating times in parameters P33-P44. The
adjustment of time values resulting from time registration is only necessary for updating purposes
when plant components are replaces.
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