Raypak XTherm Series Installation & Operating Instructions Manual page 26

MASTER
VERSA
MASTER
Wiring the Optional 0–10 Volt Building
Control Signal
1. A signal from an energy management system
may be connected to the XTherm boiler. This sig-
nal should be a 0-10 volt positive DC signal, and
an energy management system can be used to
control either the setpoint temperature of a single
XTherm or a cascade of up to 4 boilers, or the
firing rate of a single XTherm boiler.
2. To enable this remote control function, set DIP
switch 5 to the UP position on the PIM. DIP
switch 5 Toggles between an EMS (UP) signal
or a demand signal from the VERSA (DOWN).
DIP switch 2 on the PIM toggles between a
Direct Drive (UP) input and a Target Temperature
(DOWN) setpoint.
3. For a 4-20mA application, refer to the VERSA IC
manual (Cat. 5000.72).
4. Connect an Energy Management system or other
auxiliary control signal to the terminals marked
0-10V (+/-) on the field wiring terminals (see
Fig. 30: XTherm Cascade System Wiring
Wiring the Cascade System
Communication Bus
1. Designate the primary boiler as the master boiler/
2. It is recommended that the shortest length cable
26
Fig. 29). Caution should be used to ensure that
the +0-10V connection does not create a short to
ground.
boiler1 by leaving DIP switch 2 on the VERSA in
the ON position. All other VERSA controls require
DIP switch 2 to be toggled OFF, designating them
as followers. Follower VERSA boards are ignored
by their corresponding PIM modules. Use stan-
dard 18 AWG wire to connect the master VERSA
to the PIM on the followers. A total of 3 followers
can be connected to the VERSA on the master.
For systems requiring more than 4 connected
boilers, an external sequencer such as the Raypak
Temp-Tracker Mod+ Hybrid can be used.
possible be used to reach between the boilers.
Do not run unprotected cables across the floor or
where they will become wet or damaged. Do not
FOLLOWERS