Brian GT NIGC, Power supply voltage

[kanaddict]

Hi,

My NIGC is almost done, but I need to be sure that my power supply board is OK. When I measure the voltage from V+ to +PGND on my power supply board, I get 73V
I was wondering if it's OK

I use a Plitron toroidal transformer (2 x 22V @300VA).

Thanks for your help

[Nuuk]

When I measure the voltage from V+ to +PGND on my power supply board, I get 73V

No, it should be half of that!

[Peter Daniel]

I'm still puzzled how it's even possible with a transformer you have, unless you connected secondaries in series?

[Nuuk]

Actually, each rail should be about 31-32 VDC. It does seem strange that you have 73!

Disconnect the PSU section from the PCB and measure your voltages (AC) after the trasnformer, then the rails coming off the rectifiers bridges.

[Peter Daniel]

And remove those 50V rated capacitors from the board

[kanaddict]

Originally posted by Nuuk
Actually, each rail should be about 31-32 VDC. It does seem strange that you have 73!

Disconnect the PSU section from the PCB and measure your voltages (AC) after the trasnformer, then the rails coming off the rectifiers bridges.

Hi,

I already took some measure after the transformer and I got 24VAC (I dont understand why I don't get 22).

When reading your post, Ijust saw that you said 31-32 VDC. When I said 73V, it was 73 VAC ..... Maybe a beginner mistake

Please let me know if I should measure the VDC instead of the VAC !

Thanks !

[kanaddict]

Originally posted by Peter Daniel
I'm still puzzled how it's even possible with a transformer you have, unless you connected secondaries in series?

Hi Peter,

No, they are not connectec in series

Regards,

[Nuuk]

I already took some measure after the transformer and I got 24VAC (I dont understand why I don't get 22).

Your mains voltage is possibbly a little higher.

Yes, after the rectifier bridge which changes the AC into DC, you should be measuring with your meter set to DC.

[kanaddict]

Originally posted by Nuuk


Your mains voltage is possibbly a little higher.

Yes, after the rectifier bridge which changes the AC into DC, you should be measuring with your meter set to DC.

Thanks a lot !

I took the time to read a part of your guide and the answer to my question was there

I will finish to read it and this will prevent me from asking other basic questions

Thanks a lot !

[kanaddict]

Originally posted by Nuuk


Your mains voltage is possibbly a little higher.

Yes, after the rectifier bridge which changes the AC into DC, you should be measuring with your meter set to DC.

Hi,

I have a last question. The power supply board is already connected to the each channel PCB. I could cut the wire to measure the VDC, but I'm wondering if the measures I took (3 days ago) from V+ to +PGND and V- to -PGND (both 73VAC) could tell me that the power supply is well assembled ? (It's a very simple assembly and I really dont think that I maid a mistake) Any possibble calculation that I could use

If not, I'll cut the wire

Thanks again !

Daniel