Raypak 5000.72A, Installation & Operating Instructions Manual

Page: 53 / 80

53
MASTER MASTER
FOLLOWER FOLLOWER
0 0
8 8
6 6
R R
1 1
4 4
2 2
240VAC/1PH 240VAC/1PH
SYSTEM PUMP
SYSTEM PUMP
TERMINAL BLOCK TERMINAL BLOCK
L1 L1
DEDICATED DEDICATED
240VAC POWER
240VAC POWER
A A
B B
240VAC COIL 240VAC COIL
PUMP PUMP
RELAY
RELAY
240VAC/1PH 240VAC/1PH
USE COPPER CONDUCTORS ONLY USE COPPER CONDUCTORS ONLY
IND DHW IND DHW SYSTEM SYSTEM BOILER BOILER
PUMP DRY CONTACTS PUMP DRY CONTACTS
L2 L2 GND GND L1 L1
240VAC/1PH 240VAC/1PH
USE COPPER CONDUCTORS ONLY USE COPPER CONDUCTORS ONLY
IND DHW IND DHW SYSTEM SYSTEM BOILER BOILER
PUMP DRY CONTACTS PUMP DRY CONTACTS
L2 L2 GND GND
TERMINAL BLOCK TERMINAL BLOCK
Fig 38: Parallel Pump Wiring Diagram for MVB
®
/ XTherm
®
2503 - 4505
Parallel Pump Wiring Description
In the event of losing the Master unit, Follower units
are made capable of operating the System and IND
DHW pumps (as required) in “limp-along” mode (see
page 62). The System pump outputs from each cas-
cade member must be connected in parallel to activate
the system pump during “limp-along” operation. This
configuration will allow the system to continue to oper-
ate during Master unit failure or lose of the Master unit
WARNING: Failure to properly install and/or wire
the System pump and IND DHW pump may result in
a system failure during limp-along mode as well as
damage to the equipment.
VERSA
®
board. The IND DHW pump (if applicable)
must be also connected in parallel from each individ-
ual cascade member output to ensure functionality
during “limp-along”.
The following wiring diagrams illustrate the proper par-
allel connections method to be used for the System
Pump. The same concept must be applied to the IND
DHW pump, when applicable.