You said before that voltage goes up when you reduce current. When your output voltage is right measure Vbe and Vgs on all the semis.
Also try with an easier dummy load 10 to 15k.
See what happens when you up the current. Readings change?
My impression is that something is wrong on your setup and reg is working fine.
I built it many times and it' s difficult to go wrong.
Also try with an easier dummy load 10 to 15k.
See what happens when you up the current. Readings change?
My impression is that something is wrong on your setup and reg is working fine.
I built it many times and it' s difficult to go wrong.
I'm, using 4k75+4k75 = 9k25 isn't enough? I have one 15K have I to change?
BTW Resistors are OK because I measured all before to solder to know the values, also I resoldered all components to avoid cold joints, I'm really desesperate waiting your kind help.
BTW Resistors are OK because I measured all before to solder to know the values, also I resoldered all components to avoid cold joints, I'm really desesperate waiting your kind help.
When I have 240Vout the current lows till 27mA, irf840 VGS 0V, ksa1381 Q5 0,17V Q4 0,85V (marked pcb GB), sk117gr 0,17V
Now I have max. current 31mA, 840 VGS 0V, 283Vout, have I to reduce to 240Vout that is my target & then measure the current & the 840 VGS?
When having 0 Vgs on the output Mosfet you got to exchange with one that works before anything else. You could have had a destruction when it was making contact to the sink.
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Have you worked out yet how the Salas Shunt Regulator low voltage versions work?
Prior to gaining that knowledge I consider it stupidity to gamble with 240Vdc in a circuit you don't understand.
Prior to gaining that knowledge I consider it stupidity to gamble with 240Vdc in a circuit you don't understand.
Don't be so harsh Andrew; the moment you make PCBs available you will have to expect that people have some expectation of solder, plug, and play.
However, Andrew is right in that you need to be very careful with these high voltages. Someone should post a little guide of how to first test these regulators once soldering is finished. Dummy resistor, current calculations, etc. This may have very well been done, but I don't know it because I haven't been reading so carefully the thread lately.
However, Andrew is right in that you need to be very careful with these high voltages. Someone should post a little guide of how to first test these regulators once soldering is finished. Dummy resistor, current calculations, etc. This may have very well been done, but I don't know it because I haven't been reading so carefully the thread lately.
At least the board is black and doesn' t show bad!
If I was you now, I would take out ALL the semis and check them. For sure one of the dn2540 is off.
I think you have shorted something.
If I was you now, I would take out ALL the semis and check them. For sure one of the dn2540 is off.
I think you have shorted something.
@ Iko as you said I expected plug & play but possible is my fault: irf840 not isolated well from heatsink, I do the SSHV p2p and going OK 240V 60mA. Salas posted a PDF for this new version SSHV2, I followed his instructions to make it.
@George, OK I will change all semis for a new set to go fast.
@George, OK I will change all semis for a new set to go fast.
If you use the same pcb, check and clean it.
Don' t go fast, take your time.
When I first did it p2p it worked fine, because I took my time. I burned one or two semis when I was trying different ones and I thought that I gained confidence.
Don' t go fast, take your time.
When I first did it p2p it worked fine, because I took my time. I burned one or two semis when I was trying different ones and I thought that I gained confidence.
Changed all semis, diodes & burned resistors.
Max. current reached 319mA I read 0,319V across TP, Vout with this current 281V but can low the voltage to 240V the voltage is fixed 281V
If I reduce the Vout with R4 trimmer (used for adjust current) I can reach 240V but the current must reduced to 275mA I read 0,275V across TP
Max. current reached 319mA I read 0,319V across TP, Vout with this current 281V but can low the voltage to 240V the voltage is fixed 281V
If I reduce the Vout with R4 trimmer (used for adjust current) I can reach 240V but the current must reduced to 275mA I read 0,275V across TP
Did you measure the parts that you replaced?
What was burned?
Also, what Andrew said, current regulator seems to be working, voltage regulator not.
What was burned?
Also, what Andrew said, current regulator seems to be working, voltage regulator not.