User Guide

Note: All zone dampers default to the "OPEN"
position after a purge delay has occurred.
Dampers also default “OPEN” during
changeover & short cycle delays, and when
all zone demands are satisfied, and no
signals are detected from the thermostats.
Common 24vac
Constant 24vac HOT
24vac to Open a damper(s)
24vac to Close a damper(s)
Terminal M1
Terminal M2
Terminal M4
Terminal M6
ZONE DAMPER MOTOR
TERMINAL BLOCK
DESIGNATION & FUNCTION
.
.
2 Wire Spring Return Motor Wiring
EWC Controls
Spring Return Motor Wiring
A Spring Open Damper is wired to M1 & M6
A Spring Close Damper is wired to M1 & M4
M1
M2
M4
M6
{
MA-ESR
NC NO C M M
Auxilary
SPDT
End Switch
Dry Contacts
Rated for
24vac only
M1
M2
M4
M6
ZONE
MOTOR
REFERENCE THESE DIAGRAMS PRIOR TO
INSTALLATION AND POWER WIRING. DOING SO WILL
SAVE TIME AND LABOR LATER ON.
Figure 4a
Figure 4c
Figure 5
All Models ND & URD Damper Wiring
4
6
1
Figure 4b
M1
M2
M4
M6
ZONE
MOTOR
On all these dampers and most older style
dampers, including competitor’s dampers,
always wire up number to number.
Do not overload the NCM300 Thermal
Circuit Breaker. Use a 24vac UL listed
transformer at 60va maximum power
rating!
Figure 6
EWC Controls Inc. 385 Highway 33 Englishtown, NJ 07726 800-446-3110 FAX [phone] E-Mail- [e-mail]
5
Either one
Not both
DAMPER WIRING
Multiple Damper Wiring on a Single Zone, using a Separate Transformer
and an Isolating Relay. Maximum of 6 dampers per 40 va transformer.
M1
M2
M4
M6
ZONE
MOTOR
4
6
1
4
6
1
4
6
1
2
1
3
COIL
24 vac
NC
NO
C
R1 Isolation Relay
SPDT action with 24 vac coil
Relay is shown de-energized.
All dampers are closed.
To Line Voltage
Provide over current
protection
4
6
1
Separate 24 vac
Transformer
L1
L2
H
C
Multiple ND or URD
Damper Wiring on a
Single Zone Terminal
Block
4
6
1
M1
M2
M4
M6
ZONE
MOTOR
4
6
1
4
6
1