Honeywell SCS-8 User Manual

152 SCS Series Manual — P/N 15712:L 7/18/16
Ratings and Wiring Diagrams HVAC Wiring Diagrams
Figure 5.43 Fan Control - HVAC Switch Group Type 4
Figure 5.43 depicts a fan in an HVAC system with the capability of OFF control, switch group type 4. In the above configuration, the
CON
OFF⁄CL
CM is deactivated. The CON
OFF⁄CL
CM controls a normally closed contactor which switches power to the fan (the contactor is
used when the power being switched is greater than 24 volts). When the CON
OFF⁄CL
CM is deactivated, the contactor is closed, thus allowing
the EMS to freely control the fan. In this case the EMS is OFF, so no power is being supplied to the fan. When no power is supplied to the fan,
the fan is OFF. When the CON
OFF⁄CL
CM is activated, the normally closed contactor opens, thus cutting any power to the fan that was being
supplied by the EMS.
Power Source
1b listed
contact
Service
Disconnect
Switch
Power Return
Listed
24 VDC
Power Source
FCM-1
CON
OFF/CL
CM
(deactivated)
fan-h4-fs-2.wmf
SLC Loop
FAN OFF
Listed contact
for Energy
Management
System
Energy Management System
Listed
24 VDC
Power Source
*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.

Honeywell SCS-8 Specifications

General

Brand	Honeywell
Model	SCS-8
Category	Control Unit
Language	English