User Guide

C
PO
PC
D
A
M
P
E
R
Figure 5d
Several Spring Open Dampers on a Single Zone.
Separate Transformer with Isolating Relay.
Maximum of 3 Spring type dampers
per 40 va transformer.
Isolation Relay Wiring
SPST action with 24vac coil
Relay is shown de-energized.
All dampers are OPEN
To Line Voltage
Provide over current
protection
Separate 24vac
40va
Transformer
L1
L2
H
C
NO
C
MA-RSD
MA-RSD MA-RSD
RELAY
COM PO
PC
4
6
1
Note: All zone dampers default to the "OPEN"
position after a purge delay and when all zone
demands are satisfied, and no signals are
detected from any zone thermostats.
24vac Common (Neutral)
24vac Power to Open a Damper
24vac Power to Close a Damper
Terminal C
Terminal PO
Terminal PC
ZONE DAMPER MOTOR
TERMINAL BLOCK
DESIGNATION & FUNCTION
Note: The 500mA Damper Circuit Breaker limits how many
dampers can be directly connected to a single terminal
block. You can connect up to eighteen (18) genuine ND,
URD, or SID dampers to a single terminal block before relay
isolation is required. You can connect only one (1) RSD or
Competitor’s Spring type damper to a single terminal block
before relay isolation is required.
Figure 4
DO NOT overload the UT3000’s Damper Motor
Circuit Breakers. If you need to connect more
than one (1) Spring Type Damper to a single
terminal block, use figure 5d to separate and
isolate those dampers.
Figure 5c
EWC Controls Inc. 385 Highway 33 Englishtown, NJ 07726 800-446-3110 FAX [phone] E-Mail- [e-mail]
11
DAMPER WIRING
Three or More ND, URD, SID Dampers
on a Single Zone Terminal Block
No Isolation is Required
C
PO
PC
D
A
M
P
E
R
.
Figure 5b
.
EWC Controls Typical
Spring Return Motor Wiring
Any Spring Open Damper is wired to C & PC
Any Spring Close Damper is wired to C & PO
C
PO
PC
D
A
M
P
E
R
MA-RSD
C
PO
PC
D
A
M
P
E
R
Figure 5a
C
PO
PC
D
A
M
P
E
R
Genuine ND, URD & SID Damper Wiring
COM PO
PC
4
6
1
COM PO
PC
4
6
1
COM PO
PC
4
6
1
Current Draw for a ND, URD, or SID Damper = 26mA
Current Draw for a Spring Type Damper = 400mA
On all these dampers and most older style
dampers, including competitor’s dampers,
always wire up number to number or by terminal
designations. (Com to Com)(PO to PO)(PC to PC) (1-1)(4-4)(6-6)