I have 2 bridge rectifiers that have different ohm readings. They are
GBPC3504. Can you explain to me how to test them out of circuit. I'd
appreciate it.
I'll buy you a beer next time I'm in the Ft. Myers area.

On Thursday, September 25, 2014 9:51:14 AM UTC-4, Harrold wrote:
I have 2 bridge rectifiers that have different ohm readings. They are

GBPC3504. Can you explain to me how to test them out of circuit. I'd

appreciate it.

I'll buy you a beer next time I'm in the Ft. Myers area.

I'm not Greg, but...

The device has four terminals, two marked with + and - which are the DC outputs, and two marked with ~ which are the AC inputs. There are four diodes internally. Diodes will pass current in one direction only, so using an ohmmeter if you placed the meter leads across a good diode in one direction it will show a low resistance, flip the leads over and it will read infinity (open circuit). A bad diode can either fail shorted (low resistance in both directions) or open.

Now your device is square with one corner cut off. That's the + lead.
https://www.fairchildsemi.com/package-drawings/GB/GBPC04A.pdf

With the + terminal at the top left, check the top two terminals (+ ~) in both directions, they should read like a good diode. Then moving clockwise to the left two terminals (~ -) and do it again. Then the bottom two (- ~), then the left two (~ +). If it fails across any of the pairs of terminals, it's bad.

On Thursday, September 25, 2014 12:29:36 PM UTC-4, wrote:
On Thu, 25 Sep 2014 08:34:25 -0700 (PDT), wrote:



GBPC3504



That appears to be the standard square package with push on terminals.

It is 400v PIV at 35a. Mouser says it is obsolete.

There are plenty of substitutes for this.

Digi-key, Allied and MCM all have stock. $3 to $5 each.

On 9/25/2014 12:29 PM, wrote:
On Thu, 25 Sep 2014 08:34:25 -0700 (PDT), wrote:

GBPC3504

That appears to be the standard square package with push on terminals.
It is 400v PIV at 35a. Mouser says it is obsolete.
There are plenty of substitutes for this.

I ordered 4 off the internets yesterday. They should be here tomorrow.
Meanwhile I bought one at radio shack rated at 50 V not 400 V. The
diodes read infinity in one direction and about 2 meg in the other. one
of the other bridges had about a 10 to 1 F to B ratio and the other had
about a 20 to 1 ratio.
Thanks for your help.

BTW We just got back from Wyoming, Montana, N Dakota and S Dakota. The
scenery was spectacular.

On Thursday, September 25, 2014 1:47:28 PM UTC-4, Harrold wrote:
On 9/25/2014 12:29 PM, wrote:

On Thu, 25 Sep 2014 08:34:25 -0700 (PDT), wrote:



GBPC3504



That appears to be the standard square package with push on terminals.

It is 400v PIV at 35a. Mouser says it is obsolete.

There are plenty of substitutes for this.



I ordered 4 off the internets yesterday. They should be here tomorrow.

Meanwhile I bought one at radio shack rated at 50 V not 400 V. The

diodes read infinity in one direction and about 2 meg in the other. one

of the other bridges had about a 10 to 1 F to B ratio and the other had

about a 20 to 1 ratio.

Thanks for your help.



BTW We just got back from Wyoming, Montana, N Dakota and S Dakota. The

scenery was spectacular.

Yeah, and you weren't keeping us very well posted. Let's see some pictures!

On 9/25/2014 2:50 PM, John H wrote:
On Thursday, September 25, 2014 1:47:28 PM UTC-4, Harrold wrote:
On 9/25/2014 12:29 PM, wrote:

On Thu, 25 Sep 2014 08:34:25 -0700 (PDT), wrote:



GBPC3504



That appears to be the standard square package with push on terminals.

It is 400v PIV at 35a. Mouser says it is obsolete.

There are plenty of substitutes for this.



I ordered 4 off the internets yesterday. They should be here tomorrow.

Meanwhile I bought one at radio shack rated at 50 V not 400 V. The

diodes read infinity in one direction and about 2 meg in the other. one

of the other bridges had about a 10 to 1 F to B ratio and the other had

about a 20 to 1 ratio.

Thanks for your help.



BTW We just got back from Wyoming, Montana, N Dakota and S Dakota. The

scenery was spectacular.

Yeah, and you weren't keeping us very well posted. Let's see some pictures!


I can email you some and you can post them. How's that

On Thursday, September 25, 2014 3:21:23 PM UTC-4, Harrold wrote:
On 9/25/2014 2:50 PM, John H wrote:


Yeah, and you weren't keeping us very well posted. Let's see some pictures!





I can email you some and you can post them. How's that

Nah. Email 'em, but I'll only post the ones that are great enough for me to take the credit - a la the owl pictures!