COOLING
FANS
Service Manual M4 - M10
16.5.2000
Page
126
11.
COOLING
FANS
11.1 General
Cooling fans is used to blow fresh air through cooling elements and cool down
components attached to cooling element. Proper cooling is very important to extend
lifetime of converter.
11.2 Main fans
DC fans ( 24V ) is used in all frame sizes up to M6 and all sizes above that is equipped
with AC fans. Expected lifetime for cooling fans in maximum allowed ambient
temperature is at least 50 000h.
11.3 Warnings
AC fans rated voltage is 230Vac which is supplied by autotransformers. Primary of
autotransformer is connected to the mains phase to phase voltage. Correct tapping
of the autotransformer according to used input line voltage has to be selected when
comissioning the unit.
11.4 Trouble shooting
Check that the fans are rotating correctly and the air flow inlet is from bottom
and outlet from the top of the unit. Check also that fan and heat sink are clean
and if necessary clean them by compressed air.
Fan windings can be checked with multimeter by measuring the DC
resistance. See Picture 11.4.1 for correct DC-resistance values. Values can
vary ~10%. Measure also value of the start capacitor, 3
μ
F or 4
μ
F depending of
fan type. See Spare part list.
DC resistance between connection wires
R/ohm
Name Code Type
black-brown brown-blue blue-black
AC Fan CP01038 D2E133-AM47 190 125 66
AC Fan CP01328 D2E133-DM47 190 125 66
AC Fan CP01187 D2E146-CD51-09
110 66 43
Picture 11.4.1 Table of fan winding DC-resistance