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Ph: 1-800-446-3110

Fx: 1-732-446-5362
EWC Controls, Inc.
385 Highway 33
Englishtown, NJ 07726
Motorized Round Dampers
Model URD
A single blade round damper with a (2) two position, 24 volt motor. The motor is powered both ways - powered open and powered closed. The motor features LED's that indicate the position of the motor whether open or closed. The LED's are colored RED for closed and GREEN for open. These indictors are a failsafe measure meaning that they will not illuminate until the blade of the damper has gone to its full open or full closed position. The motor is a 3 wire hook-up with a common, a power open leg and a power closed leg. The available sizes are 4" - 6" - 7" - 8" - 9" - 10" - 12" - 14" - 16"-18"-20". It can also be purchased with an S1A end switch, as a URD-L (no motor), or as a URD-LM24 SR-T (modulating motor).
Model RSD
RSD Damper
The RSD has a spring return motor actuator. The RSD includes a travel limiter to prevent full closure, if so desired. It does not have LEDs or an end switch. The damper is field reversible from power closed/spring open to power open/spring closed. Available sizes are 4" - 6" - 7" - 8" - 9" - 10" - 12" - 14" - 16"-18"-20". It can also be purchased as a URD-LF24 (24 volt, 35 in/lbs, spring return) or a URD-LF120 (120 volt, 35 in/lbs, spring return). Click here for submittal sheet.
The MA-ND5 (power open/power close) motor actuator cannot be used to replace an existing MA-RSD (spring return) motor actuator, nor can an MA-RSD replace an MA-ND5.
Model SID
SID damper
SID sketch
SID sketch 2
The SID (Slip-In-Damper) is a user-friendly retrofit damper. With a single cut the SID can be installed in seconds. Due to it's 1.5VA actuator up to 20 SIDs can be controlled from a single EWC Controls zone panel with a 40VA transformer. The optional S1A end switch allows for increased flexibility. Available sizes are 4" - 5"-6" - 7" - 8" - 9" - 10". Click here for submittal sheet.
Model URD-SRE120
URD SR120 damper
The URD-SRE120 is a 120 volt round spring return style damper. It does not have LEDs. It can be used in stand alone applications and CANNOT be used with any of the Ultra-Zone zone panels (the panels are 24V, the damper is 120V). Available sizes are 4" -5"- 6" - 7" - 8" - 9" - 10" - 12" - 14" - 16".