Bridge Rectifier help

[orion311976]

I have a little air compressor with a 3 Amp Single - Phase Silicon Bridge Rectifier and wanted to replace it but not sure what I need to build it. I don't have a spare that matches the specs and thought I might be able to build one with diodes. Any help or suggestions would be appreciated.

 

[shrtrnd]

First.
Is your bridge JUST a bridge, or is it a module that has other components in it?
A bridge rectifier is indeed 4 diodes wired in a bridge configuration, so you can do that.
(I don't know why though, you can get a replacement bridge at 3A for less than $5)
Do you have a part number on the bridge you're presently trying to replace?

 

[orion311976]

Yep, it's a KBPC110. Looked it up on NTE's cross reference and read about it, don't really have any money to put toward this compressor/side project. I know I can make one with diodes but been awhile since I've built anything, my last project was a LED nightlight completely out of junk parts and designed the circuit with a little bit of help from another site. I been mainly working mechanics the last 3 yrs. with a little computer programming. I mainly needed conformatiom on the actual parts I have.

 

[duke37]

As shrtnd says, four diodes can be used to make a bridge. The KBPC110 is 1000V 3A and four !N5408 diodes (1000V 3A) would do the job. The diodes are meant to be cooled through the leads so should be soldered to a substantial terminal if to be used at full current. The bridge rectifier is cooled by being bolted to a heat sink.

 

[orion311976]

Well, thats probably why it went out, cause they had no heat sink, just a little fan blown on it. It's a cheap Cambell and Hausfeld comp. anyway, the whole circuit board consisted of this rectifier and a 104K 600V capacitor and fuse. SOMEONE, not mentioning anyone special that gave this to me wrapped foil around the fuse, so I gues I'll be check'n the little DC motor and brushes before I try out my new circuit.LOL, can't complain too much for free Shtuff.... Thanks for all the help needed the numbers for the diodes. Gett'n back to electronics more now so I'll be a very avid and eager member to this site...

 

[orion311976]

One more think a 104K 250V would probably be okay instead of a 600V..right? Cause 600V would fry the fan and motor.

 

[Resqueline]

The original bridge going out is probably more related to "chance" rather than lack of cooling or overloading. A bridge made of 1N5408's should be good for 6A though.
A 100nF (= 0.1uF) 250V AC X2 rated capacitor should be ok. The original 600V capacitor rating is probably DC, which translates to it tolerating 400V AC.
Notice that the mentioned voltages is what the capacitor stands before blowing up, not what is delivered to the motor. It's the mains voltage that determines that.

 

[orion311976]

Okay thanks again. Now I just gotta remember where I put those diodes cause I pulled a set out of something and I knew I'[d need them...LOL