Rheem Raypak Hi Delta H Series Installation & Operating Instructions Manual page 31

Fig. 36: Cascade Master Pumps
5. Connect the Enable/Disable wiring to terminals 11
and 12 on the field wiring strip located on the
Master boiler (See Fig. 33). This connection must
be provided through dry contacts closure.
NOTE: This dry contacts closure can come from a
room thermostat or a remote relay. No power of any
kind should be applied to either of these terminals.
Cascade Follower Pump
and Sensor Wiring
1. Once the primary boiler has been identified, addi-
tional boilers will be designated as follower boilers.
Ensure dip switch 2 on each follower VERSA is set
to the OFF/Down position.
2. For each follower boiler, connect the boiler pump
enable wires to the terminal block at the rear of
each unit. The connections are dry contacts rated
for pilot duty only (5A maximum).
3. For Cascade configurations System pump (all
models) and DHW pump (H models) Follower out-
puts must be connected in parallel order to
support operation durning "Limp Along" mode. For
detailed wiring instructions see VERSA IC manu-
al, catalog 5000.72.
Modbus BMS Communication
The VERSA IC control is equipped as standard with a
communications port for connectivity to building
automation via Modbus protocol. Refer to the VERSA
IC manual (5000.72) for further information.
Fig. 37: VERSA Follower
Alarm Connection
An alarm annunciator or light may be connected to the
alarm contacts on the field wiring terminal strip. The
Alarm Contacts are 3A rated dry contacts on a normal-
ly-open relay that close during fault or lockout
conditions, and the maximum voltage across the con-
tacts is 30 VAC or 30 VDC. See the Field Wiring as
shown in Fig. 33.
In a cascade system, in the event of an alarm condi-
tion at one or more units, all alarm contacts within the
cascade will be energized indicating a fault condition.
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