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hantarex polo 28 blows fuse
perjmolsen:
TP1 needs to be around +310V / +330V but mine is only 48V DC ???
When measuring TP1 - I use chassis as ground, is that not the correct way?
perjmolsen:
I used the wrong ground.
Tried the ground at the heatsink (where T101 is)
Now I have 285-295V at TP1... I assume the switching is caused by the PSU is turning on and off...
perjmolsen:
TP3 I have jumping volts.. up to max 0.5VDC
TP4 I have 12-16V
perjmolsen:
Tested some more..
And concluded that it must be my transformer that has an issue.
Because if I disconnect the lightbulb then the b+ volts rises to 170, then i connect the bulb again just to not get the volt to rise to far.
So when the volt rises, then the main parts in the psu must be OK.
Then when the bulb is connected the trafo starts to make small clicking noises again.
perjmolsen:
I refuse to give up..... ;D
So i have testet the transformer for shorts.. no shorts at all
Both the primary side and the secondary side tests without short.
Note that on the picture below the pin numbers on the primary side is my own values/number listing... I could not figure out of the pin numbers in the documentation.
So my next step is to change the R111,R112,R113 (1.5Ohm Resistors) if they are out of spec they will cause the Power Supply to oscillate with no load but does not run with a load. (I have read that in another old post)
I test mine as:
R111 = 1.4
R112= 1.6
R113= 1.6
So when I get some 1.5 Ohm I will try to change them.
I have already changed or tested all the other componetns arround the spms ic.