*LCU - Take Control of the Economizer Actuator with 0 - 10 VDC Signal on unit With or Without ReliaTel or Symbio Control
- Sometimes the controls contractor (non-Trane) will want to take control of the economizer or motorized damper actuator. They normally want to modulate the actuator with a 2-10 volt DC signal. NOTE: When a controls contractor takes control of the economizer, they lose the ability for the unit to control to comparative or reference enthalpy, and dry bulb.
Other Question/Problem/Cause Statements:
- How can I Take Control of the Economizer Actuator with 0 - 10 VDC Signal?
- Can an outside vendor take control of our economizer?
- How can a non-Trane contractor take control of our economizer?
- How can I control the economizer to open fully when fan is running and close the economizer shut when unit is off?
- How can the economizer open 100% when fan is running and shut closed when unit is turned off?
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Can a third party take control of a Trane economizer?
- Taking Control of the Economizer Actuator with 0 - 10 VDC Signal
Electro-Mechanical Precedent, Voyager UCP, & Voyager III Constant Volume
If it is an Electro-Mechanical economizer, the Honeywell W7459A actuator does not have the terminals for it to be directly controlled by external inputs. However, if the actuator is removed and is replaced with the Honeywell W7399A1004 (part #MOD1301), which has a 2-10 volt input, it can be modulated. This is the ReliaTel model actuator (only) and connections can be made directly. (This actuator is a smart actuator, not a floating point actuator).
Precedent ReliaTel, Voyager ReliaTel, & Precedent Electro-Mechanical (Gray actuator only [Released Sept 2013]) NEW Precedent Symbio
On the Economizer Control Actuator, remove the screw in the center of the actuator module. Remove the actuator module (this will not be used). Then, remove the wiring from the module. (Skip this step for Precedent with Symbio)
Terminals that are exposed by removal of the actuator module are 1/4" spades labeled 24 VAC, TR & TR1 and 2-10 VDC IN (+/-).
Apply 24 VAC to TR and TR1 and 2-10 VDC signal to (+/-) on 2-10 VDC IN. (This is can be infinite points)
DO NOT USE the lower terminals labeled 2-10 VDC OUT for control, they can be used as a feedback to the 3rd party BAS.
NOTE: The red and blue wires from the four pin Modbus can be used for the 24 vac power. (ReliaTel Only)
NOTE: (2-10 VDC) 2 Volts DC = Economizer closed, 10 Volts DC = Economizer 100% open
NOTE: The factory low leak economizer connections are controlled the same way. The control utilizes 2-10 VDC control with feedback.
NOTE: Symbio controlled standard economizer and motorized damper actuator is powered by P8-1 from the Fresh Air Options Module. When removing control of the economizer from Symbio, it must also be removed from the configuration. When it is removed from the configuration, the 24vac will be turned off and an alternate 24vac source will be required for the power to the actuator. It is necessary to remove the economizer or motorized damper from the config to prevent nuisance alarms related to damper operation.
Sinro Actuator, Relitel/Symbio STD Econ
RTEM Module
Precedent With Symbio Detail Low leak Econ
Symbio Fresh Air module
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.