Excel 10 W7751H Smart VAV Actuator. CSI 3-Part Specifications.

FEATURES

• Uses Echelon® LonWorks® network (E-Bus) protocol.
• Free Topology Tranceiver (FTT) high-speed 78 kilobit communications network.
• Compliant with VAV Device Object Type number 8010 functional LonMark® profile.
• Capable of stand-alone operation, but can also use E-Bus network communications.
• 120 controllers per Q7750A Excel 10 Zone Manager.
• Designed for Pressure Independent or Pressure Dependent Single or Dual Duct Variable Air Volume (VAV) control.
• Uses a Microbridge air flow sensor with patented dual integral restrictor design.
• Easy user access to air flow sensor inputs.
• Provides Proportional Integral Derivative (PID) temperature control.
• Floating hot water, two-stage electric or modulating hot water heat.
• Provides patented nonlinear floating algorithm for velocity control loops.
• Individual zone pressurization for supply and exhaust control.
• Factory configured via EEPROM with critical user parameter default values.
• Supports motion sensor interface, via network, for enhanced energy savings.
• Supports Terminal Regulated Air Volume (TRAV) concept.
• Supports pressurize and depressurize, night purge, and morning warmup sequences.
• Actuator included in W7751H mounts directly onto VAV box damper shaft and has up to 35 lb. in. torque, 90 degree stroke, and 90 sec. timing at 60 Hz.
• Both controller housing and actuator are UL plenum rated.

SPECIFICATIONS

Model

W7751G
The W7751H Smart VAV Actuator assembly is field mounted to the VAV box damper shaft similar to the mounting of a standard actuator. Field wiring 14 to 22 AWG (2.0 to 0.34 mm 2 ) passes through conduit connecting to screw terminals, located under a snap-on cover, on the bottom of the controller.

Input/Output

The W7751H is a NEC Class 2 rated device. This listing makes sure that the power consumed by the W7751H or devices it directly controls must be limited to a sum total of 100 VA. (Any devices connected to the controller must obtain power from the same transformer.) Any hardware that will be driven by the Triac outputs must have a minimum current draw, when energized, of 25 mA at 20 Vac and a maximum current draw of 400 mA at 30 Vac.

Inputs:
— Space temperature sensor.
— Remote wall module setpoint input or duct air temperature sensor.
— Remote wall module override.
— Air flow sensor.

Outputs:
— Internally wired VAV actuator (floating +).
— Internally wired VAV actuator (floating -).
— Floating heat (+) or stage 1 heat.
— Floating heat (-) or stage 2 heat.

Power Supply

24 Vac with a valid range of 20 to 30 Vac at 50/60 Hz.

Power Consumption

6 VA maximum at both 50 and 60 Hz.

Hardware

CPU:
Motorola or Toshiba 3150 Neuron® processor, containing three eight bit CPUs. Each Neuron has a unique 48-bit network identification number.

Memory Capacity:
The W7751H Smart VAV Actuator uses a 64K by 8 ROM/PROM, 512 bytes of EEPROM and 2K of RAM.

Differential Pressure Range

0 to 2.0 inw (0 to 0.5 kPa) maximum for the onboard flow sensor. Specified Sensing Temperature Range 20 Kohm NTC sensor temperature range of 45 to 99°F (7 to 37°C) with an allowable control setpoint range from 50 to 90°F (10 to 32°C) when initiated from the network and 55 to 85°F (13 to 29°C) when configured and connected to a T7770 Wall Module, T7780A Digital Display Wall Module (DDWM) or C7770A Air temperature Sensor.

Status Information

See Table 1.

Table 1. W7751G Controller LED Status Information.

Fig. 1. Functional profile of LonMarkâ VAV object details
(variables not implemented in Excel 10 Smart VAV II
Actuator are greyed, or are in bold print in
Configuration Properties).

Communications

The W7751H uses an FTT transformer-coupled communications port with manchester encoded data presented to controllers and devices on the E-Bus at 78 kilobits per second (kbs) via Echelon® communication protocol. Using the transformer-coupled communications interface offers a much higher degree of common mode-noise rejection while assuring dc isolation. The E-Bus is insensitive to polarity, eliminating installation errors due to miswiring.

The maximum E-Bus network length up to 5000 ft (1524m). For E-Bus network lengths greater than 5000 ft (1524m), see form 74-2865 E-Bus Wiring Guidelines. The maximum number of nodes per E-Bus segment is 60. Approved cable types for E-Bus communications wiring is Level IV 22 AWG (0.34mm 2 ) plenum or nonplenum rated unshielded, twisted pair, solid conductor wire.

Damper Shaft Mounting

The actuator on the W7751H mounts directly onto the VAV box damper shaft and has up to 35 lb. in. torque, 90 degree stroke, and 90 sec. timing at 60 Hz. The actuator is suitable for mounting onto a 3/8 in. (10 mm) square or round VAV box damper shaft, using the included 201391 Shaft Adapter, or onto a 1/2 in. (13 mm) square or round VAV box damper shaft. The minimum VAV box damper shaft length is 1-3/4 in. (45 mm). The W7751H is designed for vertical or horizontal mounting options with the exception that the wiring compartment may not be on top; these mounting options allow adequate air flow to keep the wiring compartmentbelow 140°F (60°C).

LonMark® Functional Profile

W7751H Controller supports the LonMark® Functional Profile number 8010 VAV Controller, version 1.0 (see Fig. 1).

Dimensions (H/W/D)

W7751H: 5-7/8 x 4-1/16 x 3-3/4 in. (149 x 103 x 95 mm).

Environmental Ratings

Operating Temperature: 32 to 125°F (0 to 50°C).
Shipping Temperature: -40 to 150°F (-40 to 65.5°C).

Relative Humidity

5% to 95% noncondensing.

Vibration

V2 level.

Corrosion

Office environment.

Approval Bodies

The W7751H is listed under UL 916 (E87741) and is also listed under cUL (E87741). The W7751H meets FCC part 15 Class B requirements. The W7751H conforms to requirements per European Consortium standards EN50081-1 (CISPR 22 Class B) and EN 50082-1 (IEC 801-2, IEC 801-3 and IEC 801-4) for CE mark labeling.

Accessories

— Excel 10 T7770 Wall Modules.
— T7780A DDWM.
— Excel 10 C7770A Air Temperature Sensor.
— Excel 10 Q7750A Zone Manager.
— Excel 10 Q7751A,B Router.
— Excel 10 Q7752A,B Serial Interface Adapter.
— Excel 10 Connector Cable 205979 from the Excel 10 Q7752A Serial Interface Adapter to Excel 10 Controller or Wall Module.
— 209541B Excel 10 Termination Module.
— 201052A,B,C Auxiliary Switches (one, two or three switches).