25-85 Relay ON Time
Array [2]
0
h
*
[0 –
2147483647
h]
Readout of the value for Relay ON time. The
Cascade Controller has set counters for the
compressors and for the relays that control
the compressors. Compressor cycling is always
done based on the relay counters, otherwise
it would always use the new compressor if a
compressor is replaced and its value in
parameter 25-84 Pump ON Time
counter is
reset. In order to use
parameter 25-04 Pump
Cycling
, the Cascade Controller is monitoring
the Relay ON time.
25-86 Reset Relay Counters
Option:
Function:
[0]
*
Do not reset
[1]
Do reset
Resets all elements in
parameter 25-85 Relay
ON Time
.
6.14.6 25-9* Service
Parameters used in case of service on one or more of the
compressors controlled.
25-90 Compressor Interlock
Array [2]
In this parameter, it is possible to disable one or more
of the fixed lead compressors. For example, the
compressor will not be selected for staging on even if it
is the next compressor in the operation sequence. It is
not possible to disable the lead compressor with the
Compressor Interlock command.
The digital input interlocks are selected as
[130 – 132]
Compressor 1-3 Interlock
in parameter group
5-1* Digital
Inputs
.
[0]
*
Off The compressor is active for staging/destaging.
[1]
On The Compressor Interlock command is given. If a
compressor is running it is immediately destaged. If the
compressor is not running it is not allowed to stage on.
25-91 Manual Alternation
Option:
Function:
[0]
*
0 = Off -
Number of
Compressors
This parameter is only active if the options
At Command
or
At Stating or Command
are
selected in
parameter 25-50 Lead Compressor
Alternation
.
The parameter is for manually setting of
what compressor to be assigned as variable
speed compressor. The default value of
Manual Alternation is
[0] Off
. If a value other
25-91 Manual Alternation
Option:
Function:
than
[0] Off
is set, the alternation is carried
out immediately and the compressor that is
selected with Manual Alternation is the new
variable speed compressor. After the
alternation has been carried out, the Manual
Alternation parameter is reset to
[0] Off
. If
the parameter is set to the number which
equals the actual variable speed
compressor, the parameter will be reset to
[0] immediately after.
Parameter Descriptions
Operating Instructions
MG34M422
Danfoss A/S © Rev. 2013-07-03 All rights reserved.
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Summary of Contents for VLT CDS 303
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