Basic Documentation

116/332
Siemens Universal controllers RMU710B, RMU720B, RMU730B CE1P3150en
Building Technologies Aggregates 03.10.2011
10.2.8 Precommand
For each pump, an associated precommand can be configured. This allows e.g. to
open a damper or valve prior to actual pump start as well as shut the damper
delayed following pump switch-off.
Main menu > Commissioning > Extra configuration > Aggregates > Pumps > Pump 1...4 >
Operating line Adjustable values / remarks
Precommand ---, N.Q1, N.Q2, ... (free outputs only)
The precommand allows for starting or stopping the pumps either simultaneously
or delayed. Delayed switch-on/switch-off is set via the Precommand runup time
and Precommand rundown (coasting) time.
Main menu > Commissioning > Settings > .... or
Main menu > Settings > Aggregates > Pump 1...4 >
Operating line Range Factory setting
Precommand runup time 00.00…59.59 m:s 00.30 m:s
Precommand rundown time 00.00…59.59 m:s 00.30 m:s
0
I
PcmdRndw
PcmdRnup
DlyOn
DlyOff
3150D11en
Start-
condition
Precommand
Pump
On
Off
On
Off
DlyOn =
Switch-on delay
DlyOff =
Switch-off delay
PcmdRnup =
Precommand runup time
PcmdRndw =
Precommand rundown time
10.2.9 Precommand checkback signal
A precommand checkback signal can be configured for each pump block in
addition to the precommand. The precommand checkback signal provides
information on whether or not the precommand was implemented (e.g. via valve or
damper end position switch). Only then is the pump switched on.
Main menu > Commissioning > Extra configuration > Aggregates > Pumps > Pump 1...4 >
Operating line Range
Precommand
checkback signal
---, N.X1, N.X2, ... (digital inputs only)
If there is no precommand checkback signal during the set Precommand runup
time, a fault message appears and the pump is not started. The precommand
drops off after the precommand rundown time.
If the precommand checkback signal drops off during pump operation, the pump is
switched off immediately and the precommand drops off after the precommand
rundown time. A fault message appears. The fault message is removed only after
acknowledgement and reset.
Configuration
Setting values
Function diagram
Key
Configuration