Application Note : Dual Modulating Damper Actuator / Control (DAB/VAV)

Use Case:

Occasionally there are times when a single Smart Node modulates two dampers (separate actuators and part of not a dual-duct system) and require minor adjustments to wiring to allow seamless control.

Note: Adding another Smart Node to control the second damper only is usually not the best solution, as it can cause 'fighting' between the two Smart Node.

Solution:

While some would think that terminating the damper output of the Smart Node to both actuators is the easiest solution, the actual solution is to terminate the damper feedback signal of the first actuator to the control signal on the second actuator and then terminate the feedback signal of the second actuator to the Smart Node for accurate feedback signal monitoring.

Note: This is why the first option is not the correct solution, because if the installer were to wire the damper output of the Smart Node to both actuators, they would only be able to monitor one damper feedback and never know what was actually happening to the damper they could not terminate the feedback to.

Result:

• Easily modulate two dampers and actuators (separate) with a single Smart Node and retain accurate feedback signal monitoring.

References:

Notice Note 1.