Checkout, W7751h checkout, Step 1. wiring connections – Honeywell EXCEL 10 W7751H User Manual

Page 9: Verify termination module placement, Step 2. startup broadcasting the service message, T7770d wall module

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EXCEL 10 W7751H SMART VAV ACTUATOR

9

95-7553—04

Fig. 18. W7751H discharge air sensing

(For Note 2 instructions, refer to Fig. 15.)

CHECKOUT

W7751H Checkout

Step 1. Wiring Connections

Inspect all wiring connections at the W7751H and the T7770

terminals, and verify compliance with installation diagrams. If

any wiring changes are required, first be sure to remove

power from the controller before starting work. Pay particular

attention to:

— 24 Vac power connections. Verify multiple controllers being

powered by the same transformer are wired with the

transformer secondary connected to the same input

terminal numbers on each W7751. See Fig. 10. (Controller

configurations are not necessarily limited to three devices,

but the total power draw including accessories cannot

exceed 100 VA when powered by the same transformer.

See System Engineering form 74-2949 for power wiring

recommendations.)

— Controller wiring. Be sure that each controller is wired

(terminal 3 on the W7751H, 28 on the W7751B, and 32 on

the W7751D,F) to a verified earth ground using a wire run

as short as possible with the heaviest gauge wire available,

up to 14 AWG (2.0 mm

2

) with a minimum of 18 AWG

(1.0 mm

2

) for each controller in the group. See Fig. 10.

— Verify Triac wiring to external devices uses the proper load

power/24 Vac Hot terminal (terminal 1 on the W7751H).

NOTE: All wiring must comply with applicable electrical

codes and ordinances. Refer to installation diagrams

for specific wiring.

Verify Termination Module Placement

The installation wiring diagrams should indicate the locations

for placement of Termination Module(s). Refer to the

L

ON

W

ORKS

® Bus Wiring Guidelines, form 74-2865, and the

Excel 10 FTT Termination Module Installation Instructions,

form 95-7554. Correct placement of the termination module(s)

is required for proper L

ON

W

ORKS

® Bus communications.

Step 2. Startup

Broadcasting the Service Message

The Service Message allows a device on the L

ON

W

ORKS

®

Bus to be positively identified. The Service Message contains

the controller neuron ID number and, therefore, can be used

to confirm the physical location of a particular Excel 10 in

building.

There are three methods of broadcasting the Service

Message from an Excel 10 W7751H Controller:

1. Physical service pin on controller:

a. Remove the plastic cover and the white button is

located next to the terminal strip.

b. Momentarily pressing this service pin broadcasts

the Service Message on the network.

2. Using the wall module bypass pushbutton:

a. By pressing the wall module bypass/override button

for more than four seconds, the controller sends the

Service Message.

b. This functionality is supported in firmware version

1.2.15 or higher.

1

2

3

4

5

6

7

8

9

10 11 12

EARTH

GROUND

24 V

A

C

COM

OUT

1

OUT

2

E-BUS

COMM

OUT

COMM

IN

24 VAC

W7751H

C7770A AIR

TEMPERATURE SENSOR

M10527A

1

2

2

2

WALL MODULE

EAR

TH

GND

SENSOR

BYP

ASS

LED

NOT EARTH GROUND

JACK FOR

E-BUS

NETWORK

ACCESS

7 6

9 8

5 4 3 2 1

T7770D

WALL

MODULE

SET

PT

GND

SENSOR

BYP

ASS

LED

E-BUS

E-BUS

1

2

3

EARTH GROUND WIRE LENGTH SHOULD BE HELD TO A MINIMUM. USE

THE HEAVIEST GAUGE WIRE AVAILABLE, UP TO 14 AWG (2.0 MM

2

)

WITH A MINIMUM OF 18 AWG (1.0 MM

2

), FOR EARTH GROUND WIRE.

TO ASSURE PROPER ELECTRICAL CONTACT, WIRES MUST BE TWISTED

TOGETHER BEFORE INSERTING INTO THE TERMINAL BLOCK.

NOTE: AIR TEMPERATURE SENSOR CANNOT BE USED WITH EITHER THE

T7750B OR C WALL MODULE.

MICROBRIDGE

DP SENSOR

AIR FLOW

DP PICKUP

AIR FLOW

DIRECTION

LOW

HI

2

TRIAC

EQUIVALENT

CIRCUIT

WIRED FOR MODULATING

OR STAGED REHEAT. SEE

FIG. 17 OR FIG. 18.

SET

PT

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