Excel 10 W7751H Smart VAV Actuator
The W7751H Smart VAV Actuator is a factory-combined
Excel 10 Variable Air Volume (VAV) Box Controller and an
ML6174 Direct-Coupled Actuator with De-clutch mechanism.
The actuator/controller assembly is field mounted to the VAV
box damper shaft similar to the mounting of a standard
actuator, and the controller wiring is terminated to the screw
terminals that are located under a snap-on cover. See Fig. 1.
The Smart VAV Actuator is a Free Topology Transceiver (FTT)
® compliant controller. The W7751H2025 is for
smoke control use.
The ML6174 Direct-Coupled Actuator with De-clutch
mechanism (see Fig. 2 for location) allows the installer to
manually open or close the VAV box damper connected to the
W7751H without power or software tool to command it.
The controller in the W7751H contains a Microbridge flow-
through pressure sensor and communicates via the
78 kilobaud Echelon® L
Triac output loads must draw a minimum current of 25 mA at
24 Vac, 60 Hz nominal. Triac maximum current rating: 77 mA.
The actuator on the W7751H mounts directly onto the VAV
box damper shaft and has up to 70 lb-in. torque (8 Nm), 90
degree stroke, and 90 second timing at 60 Hz.
The actuator on the W7751H can accommodate the optional
field-installed auxiliary switches.
NOTE: Mounting thermostat/sensor greater than 20 ft from
the W7751H2025 requires 14506944-001 Transient
Protectors. They must be installed on the thermostat/
sensor leads from the T7770C pins 3, 4, 5, 6, and 7.
® Bus Network.
Horizontally mount the W7751H on the damper shaft and
allow clearance for wiring, servicing and module removal.
Avoid mounting the W7751H in areas where acid fumes or
other deteriorating vapors can attack the metal parts of the
actuator, or in areas where escaping gas or other explosive
vapors are present. See Fig. 2 for mounting dimensions.
Fig. 1. Excel 10 Smart VAV Actuator.
The assembly is intended only for horizontal shaft
mounting, to assure proper heat dissipation from the
controller housing. The Smart VAV Actuator must not
be mounted with the controller at the top.