Unitor UWI-230TP, Руководство по сборке и подготовке

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EXPLANATION
Pictur
e 1
The varistor is a blue disc.
This device is for protecting the board from input
overvoltage. When there is overvoltage they
“explode” causing a short circuit most of the
times. If the extent of the short circuit is very
high, they become an open circuit.
Pictur
e
2
To check the PFC of the switching power supply
unit, carry the following measurements with a
diode tester:
Should there be a short-circuit on one of these
measurements or an “OL” instead of a numeric
value, the power board must be replaced.
Red Probe Black Probe Measure
D S “OL”
S D
0.38
G S
1.02
S G
1.05
G D “OL”
D G “OL”
A D “OL”
D A
0.34
D S G
A