Honeywell W7750A Appendix A. Using E-Vision to Commission a W7750 Controller, Sensor Calibration

EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER

W7750

31	30	29	28	27	26	25	24
								23	22
										21 20
												19	18
DI-4	DI						VAC							17	16
	GND	DI-3	DI-2	DI		VAC
				GND	DI-1	24	24	1	2	3
							COM	OUT			4	5
									OUT	OUT	OUT	OUT	6	7	8
													OUT	OUT	OUT

E

LED

BYPASS SNSR

AI

GND

SET PT

GND

AI-1

AI

A1-2

AI-3

1

OHM

GND

OHM

AI

AI-4

20VDC

2

3

4

V/mA

GND

V/mA

LONWORKS

5

6

OUT

LON

7

8

-

BUS

9

10

11

12

JACK

13

14

15

J3

STATUS

LED

M10095A

Fig. 42. LED location on W7750.

T7770C,D Wall Module Bypass Pushbutton and Override LED

Pressing the bypass pushbutton, located on the T7770C,D Wall Modules in Fig. 43, causes the override LED to display the Manual Override mode of the controller. The modes are:

T7770C T7770D

	65	70
	60	75	OVERRIDE
OVERRIDE
	55
LED		80	LED
		85	BYPASS

PUSHBUTTON

BYPASS

PUSHBUTTON

M11617

Fig. 43. The T7770C,D Wall Modules LED and Bypass

pushbutton locations.

1.LED = Off. No override active.

2.LED = Continuously on. Bypass mode (timed Occupied override).

3.LED = One flash per second. Continuous Unoccupied override.

4.LED = Two flashes per second. Remote only, continu- ous Occupied override.

T7560A,B Digital Wall Module Bypass Pushbutton and LCD Display Occupancy Symbols

See Fig. 44 for the T7560A,B Digital Wall Module bypass pushbutton location.

Press and release the bypass pushbutton, located on the T7560A,B Digital Wall Modules in Fig. 44 for more than one second to cause the sun symbol on the bottom right side of the LCD display to appear. Pressing the bypass pushbutton for more than four seconds causes the controller, hard-wired to the T7560A,B, to go into continuous unoccupied override. The T7560A,B displays the moon symbol.

BYPASS

PUSHBUTTON

M17500

Fig. 44. The T7560A,B Digital Wall Module Bypass

pushbutton location.

APPENDICES

Appendix A. Using E-Vision to Commission a W7750 Controller.

NOTE: When commissioning a CVAHU W7750 Controller, E-Vision first checks that the actual hardware model (such as W7750A,B,C) is the same type which was selected from the Application Selection/Output tab. If the types do not match, the download does not occur and the user-entered values in the Application Selection screens all revert back to default values.

Sensor Calibration

The space temperature, the optional resistive and voltage/ current (W7750B,C only) inputs can all be calibrated. The wall module setpoint potentiometer can not be calibrated.

Perform the sensor calibration by adding an offset value (either positive or negative) to the sensed value using E-Vision menus (see E-Vision user guide, form number 74-2588).

When calibrating voltage/current sensors on the (W7750B,C), the offset amount entered by the user is in volts, regardless of the inputs actual engineering units. See Appendix E for information on how to derive the proper voltage value to enter as an offset during calibration.

Setting the Pid Parameters

The W7750 is designed to control a wide variety of mechanical systems in many types of buildings. With this flexibility, it is necessary to verify the stability of the temperature control in each different type of application.

51 74-2958— 1