Honeywell W7750A specifications Nema class 2 transformer voltage output limits

EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER

	27
	26
	25
VOLTAGE	24
	23
	22
SECONDARY	21
	20

OUTPUT

DEVICE

POWER

TRANSFORMER	TRIAC LINES
	TO ACTUATORS
	AND CONTACTORS

19

18

17

16

15

14

050100150200

% OF LOAD M993

Fig. 21. NEMA class 2 transformer voltage output limits.

Attach earth ground to W7750 Controller terminal 1. See Fig. 22, 23 and 24, 27 through 35.

CONNECT POWER TO TERMINALS 24 AND 25

W7750B,C
25 24	22	20
1

EARTH	M10089B
GROUND

Fig. 22. Power wiring details for one Excel 10 per

transformer.

See Fig. 23. for wiring more than one Excel 10 per transformer.

TRANSFORMER

120/240 VAC

24 VAC

	W7750B,C	W7750B,C	W7750B,C
	25 24	25 24	25 24
1	1		1

EARTH	EARTH	EARTH	M10090A
GROUND	GROUND	GROUND

Fig. 23. Power wiring details for two or more Excel 10s per transformer.

IMPORTANT

If the W7750 Controller is used on Heating and Cooling Equipment (UL 1995 U.S. only) devices and the transformer primary power is more than 150 volts, connect the transformer secondary to earth ground, see Fig. 24.

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