Wilo 22 DM, Installation And Operating Instructions Manual

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English
18 WILO SE 11/2013
6.2.4 Double pump operation
A Protect-Module C must be installed for each of the two pumps.
The double pump functions on the Protect-Module C are:
• Main/Reserve operation with automatic switching to the standby reserve pump
after 24 hours of real running time, the external control command “Ext. Off”
interrupts the running time counter.
• Switching takes place through an overlap, i.e. at the time of switching, both
pumps run simultaneously (for approx. 10 sec.). This avoids pressure surges and
undersupply in cooling and air-conditioning systems for example.
• The DIP switch 1 (figure 2b, position 1) determines which pump is the master
(MA) and which pump is the slave (SL) (function see Table 2).
• The DIP switch 2 (figure 2b, position 1) determines whether the signal contacts
“SSM” and “SBM” are individual or collective signals (function see Table 2).
• In the case of a fault in the working pump, the system switches to the standby
pump after approx. 3 sec.
Single pump Double pump
Master (MA) Slave (SL)
DIP Switch1: MA
DIP Switch2: I
Allocate terminals to Ext. Off DIP Switch1: MA
DIP Switch2: -
Allocate terminals to Ext. Off DIP Switch1: SL
DIP Switch2: -
Bridge terminals to Ext. Off
DIP Switch1: MA
DIP Switch2: I
SSM: Collective fault signal
for pump DIP Switch1: MA
DIP Switch2: I
SSM: Individual fault signal
for MA
DIP Switch2: I + II
SSM: Collective fault signal
for MA + SL DIP Switch1: SL
DIP Switch2: -
SSM: Individual fault signal
for SL
DIP Switch2: -
SSM: Individual fault signal
for SL
DIP Switch1: MA
DIP Switch2: I
SBM: Individual operating
signal for pump DIP Switch1: MA
DIP Switch2: I
SBM: Individual operating
signal for MA
DIP Switch2: I + II
SBM: Collective operating
signal for MA + SL DIP Switch1: SL
DIP Switch2: -
SBM: Individual operating
signal for SL
DIP Switch2: -
SBM: Individual operating
signal for SL
- : Setting of DIP switch not relevant
Table 2