Motorola MTR2000 T5544 Instruction / Field Service Manual page 252

CLN1220/DLN6458 – 500W Power Supply Module
6
the ac voltage is less than 85 Vrms, but more than the minimum voltage that guaran-
tees that all outputs will be in regulation at full load. For the nominal 240 Vac opera-
tion, the detect point is less than 170 Vrms but more than the minimum ac input
voltage that guarantees that all outputs be in regulation at full load.
Fan Control Line
The supply incorporates temperature sense/fan enable circuitry for controlling a
12Vdc fan mounted on the surface of the heatsink assembly. The power supply cir-
cuitry senses the internal temperature of the power supply. When the internal tem-
perature exceeds +60°C (± 5°C), +12 V is enabled at J1–1 to turn on the fan. The +12 V
fan supply is derived from the +14.2 V output. Power to the fan is off when the tem-
perature is below the set limit. The fan turns for approximately 10 seconds when
power is first applied as a diagnostic indicator that the fan is functional.
68P81096E33-D
09/30/05