8 C2428M-B (1/06)
Example: An enclosure that requires 30 VA and is installed 94 feet (28 m) from the transformer would
require a minimum wire gauge of 20 AWG.
NOTE:
Distances are calculated in feet; values in parentheses are meters.
*Minimum cable requirements:
75 ohms impedance
All-copper center conductor
All-copper braided shield with 95% braid coverage
Operation
The enclosure has a thermostatically controlled heater that is set to turn on at 50°F (10°C) and turn
off at 80°F (27°C). The defroster operates continuously.
Maintenance
Regularly scheduled maintenance prolongs the operational life and appearance of the equipment.
Clean the window regularly with a soft cloth using a mild, nonabrasive detergent and water to
maintain picture clarity.
Table B.
24 VAC Wiring Distances
The following are the recommended maximum distances for 24 VAC applications and are calculated with
a 10 percent voltage drop. (Ten percent is generally the maximum allowable voltage drop for AC-powered
devices.)
Wire Gauge
Total VA 20 AWG
(0.5 mm
2
)
18 AWG
(1.0 mm
2
)
16 AWG
(1.5 mm
2
)
14 AWG
(2.5 mm
2
)
12 AWG
(4.0 mm
2
)
10 AWG
(6.0 mm
2
)
10 283 (86) 451 (137 716 (218) 1142 (348) 1811 (551) 2880 (877)
Maximum distance from
transformer to load
20 141 (42) 225 (68) 358 (109) 571 (174) 905 (275) 1440 (438)
30 94 (28) 150 (45) 238 (72) 380 (115) 603 (183) 960 (292)
40 70 (21) 112 (34) 179 (54) 285 (86) 452 (137) 720 (219)
50 56 (17) 90 (27) 143 (43) 228 (69) 362 (110) 576 (175)
Table C.
Video Coaxial Cable Wiring Distances
Cable Type* Maximum Distance
RG59/U 750 ft (229 m)
RG6/U 1,000 ft (305 m)
RG11/U 1,500 ft (457 m)