SCS Series Manual — P/N 15712:L 7/18/16 189
HVAC Wiring Diagrams Ratings and Wiring Diagrams
Figure 5.81 EP Damper Control - HVAC Switch Group Type 15
Figure 5.81 depicts an EP damper in an HVAC system with the capability of
OPEN and CLOSED control and verification of the OPEN and
CLOSED state, switch group type 15. In the above configuration, the CON
ON⁄OP
CM is activated and the CON
OFF⁄CL
CM is deactivated. The
CON
ON⁄OP
CM controls a normally closed contactor for the pressure switch power line. When the CON
ON⁄OP
CM is activated, the normally
closed contactor is opened. When the contactor opens, power is cut from the pressure switch, which allows airflow to open the damper.
When the CON
ON⁄OP
CM is deactivated, the EMS is free to control the damper. The EMS is currently being overridden by the
CON
ON⁄OP
CM.
When power is cut from the pressure switch, the damper opens. When the damper completely opens, the damper open limit switch is
CLOSED
and the damper closed limit switch is
OPEN, indicating that the damper is in the OPEN position. The VER
ON⁄OP
MM monitors the CLOSED
position of the damper open limit switch and the VER
OFF⁄CL
MM monitors the CLOSED position of the damper closed limit switch. In this
case the VER
ON⁄OP
MM is activated and the VER
OFF⁄CL
MM is deactivated because the damper is OPEN.
FRM-1
COM
N/O
FMM-1
Airflow
PRESSURE
SWITCH
SMOKE
DAMPER
OPEN
Power Source
Listed
24 VDC
Power Source
SLC Loop
FCM-1
CON
OFF/CL
CM
(deactivated)
DEP-h15A-fs-2.wmf
Power
Return
VER
OFF⁄CL
MM
(deactivated)
N/O
COM
Limit Switch
for closed
position
ELR-47K
(use 3.9K listed ELR with FZM-1)
Pneumatic
Tubing
Energy
Management
System
1a listed
contactor
N/O
COM
Limit Switch
for open
position
VER
ON⁄OP
MM
(activated)
FMM-1
1b listed
contactor
CON
ON/OP
CM
(activated)
*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.