For proportional modulation of dampers in HVAC systems.
Actuator sizing should be done in accordance with the
damper manufacturer’s specifications.
The actuator is mounted directly to a damper shaft up to 1.05″
in diameter by means of its universal clamp, 1/2″ self centered
default. A crankarm and several mounting brackets are available
for applications where the actuator cannot be direct coupled
to the damper shaft.
The actuator operates in response to a 2 to 10 VDC, or with
the addition of a 500O resistor, a 4 to 20 mA control input
from an electronic controller or positioner. A 2 to 10 VDC
feedback signal is provided for position indication or masterslave
applications.
Operation
The actuator is not provided with and does not require any
limit switches, but is electronically protected against overload.
The anti-rotation strap supplied with the actuator will prevent
lateral movement.
The NM series provides 95deg. of rotation and a visual indicator
indicates position of the actuator. When reaching the damper
or actuator end position, the actuator automatically stops. The
gears can be manually disengaged with a button on the actuator
cover.
The NMB24-SR actuators use a sensorless Brushless DC
motor, which is controlled by an Application Specific
Integrated Circuit (ASIC). The ASIC monitors and controls the
actuator’s rotation and provides a digital rotation sensing
(DRS) function to prevent damage to the actuator in a stall
condition. Power consumption is reduced in holding mode.
Add on auxiliary switches or feedback potentiometers are
easily fastened directly onto the actuator body for signaling
and switching functions.