Chigo CS-25V3A-MA114A, Service Manual

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(1) No-load characteristics
as for the power supply 220V/50Hz, 220V/60Hz, 240V/50 Hz, power 5 ~ 8W .
transformer primary load current ≤ 20mA; power supply 115/60Hz; power 5 ~ 8W of the transformer
primary No-load current ≤ 35 mA; no-load output voltage does not exceed rated v10%.
(2) Load Characteristics
transformer at rated load conditions; the error of the secondary coil voltage should not be greater than
the requirements in Table 1;
4)
、
Output power
(1), measured current and voltage with the multimeter,and then according to P = UI, the output power
should not exceed transformer nominal requirements of ± 8%, If you exceed this requirement, you can
determine the transformer's power attenuation.
(2) According to P=U2/R,the output power shall not exceed the transformer nominal requirements of ±
8%, If you exceed this requirement, you can determine the transformer power attenuation.
5)
、
DCR
(1) turn-to-turn short circuit:
check by multimeter, select the appropriate range, measure the resistance of transformer winding,if the
deviation between real resistance with the standard resistance is great,that means the inter-turn short
circuit and outlet the open circuit.
(2) Coil Open circuit:
check by multimeter, select the appropriate range, measure the resistance.if the resistance is ∞, that
means transformer coil open circuit or open circuit.
6)
、
Insulation inspection
(1) insulating property between the shell and the iron core
Testing method:
check by multimeter, select the appropriate range, measure the resistance.if the resistance is ∞or tens
of thousands of ohms,means insulating property is good.if the measured resistance of the smaller or
0,means core screen has been destroyed.
(2) insulation between the windings
Testing method:
check by multimeter, select the appropriate range. one pen contacts with the transformer primary,the
other contacts with secondary output transformer.if the resistance is ∞ or tens of thousands of
ohms,means insulating property is good.if the measured resistance of the smaller or 0,means core
screen has been destroyed.
6
、
remote control
1), visual inspection
(1) injection parts should be no deformation, no mask loose, tilt phenomenon.
(2) The battery should be in a good elasticity with no rust.
(3) liquid crystal display without bubbles,display clear, correct, not more paragraphs, , ghosting and black.
2)
、
Function test
The battery into remote control, LCD display should clearly show the content (non-LCD display does not