ISA215-HYD module reverse engineering => involved in p1a15-error-condenser-charge-timeout

[iso14000]

so you didn't like my one?

 

[iso14000]

do you have the inline power resistor value?
it is steange to see such resistor jeopardise a voltage...
it should be very low

 

[kiev]

so you didn't like my one?

It was okay except i couldn't read it--i'm old and eyes are not so good anymore.

 

[kiev]

do you have the inline power resistor value?

There is a 100 Ohm inline on the 15V supply--is that what you wanted?

The lack of reference designators on the board is unfortunate, maybe we should come up with scheme to add some?

 

[iso14000]

okay, here find my sch in pdf print shape.
added value (they are crazy to add such a R inline with the power!), also renumbered all topos
you can zoom in as far as you want

 

[kiev]

That is beautiful--thank you.

[The 15V power supply was indicating 0.01 Amp draw by the circuit board, which would be the ~1V drop across the 100 Ohm resistor. It was probably closer to 0.012A based upon scope measurements.]

 

[iso14000]

I really don't know what was in designer's head .
adding a resistor into a power line is a newbee fault, logical circuit really don't like that.
moreover if it is for filtering purpose, the guy added a cap in // so he also jeopardise the "filter behaviour", it is ridiculous.

 

[Vadimchik1973]

Hi ALL. Perhaps my publication on FB will help to understand the general problem :

 

[kiev]

Good Findings Vadimchik,

If you look at the pin legs of two transformers under a microscope, you can see strong loosening/degradation of the solder with obvious ovals of developing ring cracks!!!

Also under a microscope you can see an end crack in the solder of the lower terminal of the resistor. You need to solder to the maximum

This could cause an intermittent fault if not complete failure of the Hybrid circuit

 

[iso14000]

as I told before.... stifness is largely hampered by pcb milling (creepage purpose) , pin holding only at each end of the board and heavy component in the middle.