158 SCS Series Manual — P/N 15712:L 7/18/16
Ratings and Wiring Diagrams HVAC Wiring Diagrams
Figure 5.49 Fan Control - HVAC Switch Group Type 12
Figure 5.49 depicts a fan in an HVAC system with the capability of
ON and OFF control, switch group type 12. In the above configuration, the
CON
ON⁄OP
CM is deactivated and the CON
OFF⁄CL
CM is deactivated. These two control modules are always in the opposite state when the
smoke control system is in operation and are always deactivated during normal operation. The CON
ON⁄OP
CM is wired in parallel with the
EMS; when wired in parallel with the EMS the CM must be a relay module. When the CON
ON⁄OP
CM and the CON
OFF⁄CL
CM are deacti-
vated, the EMS is free to control the fan. In this case the EMS is ON, so power is being supplied to the fan. When the CON
ON⁄OP
CM is acti-
vated for smoke control, the CON
ON⁄OP
CM overrides whatever state the EMS is in and closes the normally open contactor, thus supplying
power to the fan and turning it
ON. When the CON
OFF⁄CL
CM is activated for smoke control, the CON
OFF⁄CL
CM opens the normally closed
contactor and turns the fan
OFF, overriding whatever state the EMS is in.
Power Source
1a listed
contact
Service
Disconnect
Switch
Power Return
Listed
24 VDC
Power Source
fan-h12-fs-2.wmf
SLC Loop
FAN ON
Energy Management System
CON
ON/OP
CM
(deactivated)
FCM-1
CON
OFF/CL
CM
(deactivated)
Listed
24 VDC
Power Source
1b listed
contact
FRM-1
COM
N/O.
*If the SLC device
does not match the
one in this figure, refer
to the SLC manual
appendix, which
contains wiring
conversion charts for
type V and type H
modules.
To Next Page
Loading...
Need help?
General
