Schumaker Battery chargers got around to looking

[old]

Well I finally got around to opening them both up. Both SE2001 models. Both have bad diodes in them. One puts out voltage but is 12 volts AC funny how a meter will not read AC on the DC scale. The other one also has bad diodes but those are burned out as in open the other the diodes are shorted out. Will be checking there web site in a few to see how much the diodes might be for both or them
 

[circus]

Ten years ago I found diodes for my 40 year old 10/50 amp Schumaker at a alt/starter repair shop. $2 each.
 

[old]

I know I could probably take the numbers off the ones in the charger and match them to something at radio shack that would work but prefer to get what the company used so as to maybe be closer to correct. Odd how one charger has them shorted and the other has them open
 

[ShadetreeRet]

About two years ago I bought a small 6/12 Schumacher charger from TSC, had a two year warranty.Paid less than $30.00.
Thing quit working so I called TSC and was told that if something under warranty quit the first year they generally took care of it at the store, but since it was over a year old I would have to deal with the factory. Well, shucks, it would probably cost me $10.00 or more to ship it to them. Checked it out myself. Both 6 and 12 were putting out, problem seemed to be in selector switch,looked that up and they wanted $13.00 for that! Guess I will toss it in the corner with all that other stuff that "I'm gonna fix someday".
 

[George Marsh]

Old, is it possible to rob some diodes out of an old alternator? I remember the old chrysler alternators, there were 6 diodes pressed in. The way I look at it, you could double up and use two diodes side by side, parallel, and it won't hurt a thing. My mig welder came with 4 diodes, 2 sets in parallel. When one side burnt out two diodes, I replaced them with 3 diodes in parallel.

I've never spent money on diodes. Have a box full of used ones.

George
 

[old]

I might could do that if I had them laying around but I do not. Thing the gets me is the fact it appears that these chargers use a half wave rectifier system instead of a full wave
 

[old]

These are not the little ones these are the ones you pay $100 plus for the stand up ones on wheels. Plus both where given to me because the guy figured if any body could make them work again it would be me so I have only a little time invested in them so far
 

[Brad Buchanan]

Hey Rich!

Can't figger out why this Schumacher machine doesn't work..

Was fine until the wife ran it down with the bucket truck.

Brad

 

[old]

Shoot just pull all the parts out of it making sure you have it wired right and it would probably still work just fine. Just need to weld up a box that is made from 1/2 inch steel so it is truck proof/wife proof
 

[guido]

Hello old,
Have you looked at Radio Shack? I don't know if you have one around your way. A 25 amp 50 V rectifier bridge is $4.29. I don't know what size you need. You may find one that is the right size for your charger.
Guido.
 

[George Marsh]

Old, All the chargers I've seen use only 2 diodes and a transformer that has a center tap. The output, if seen on an oscilliscope, are postiive 1/2 waves. It is still considered a full wave power supply, because there are 120 + waves per second.

Old go to http://en.wikipedia.org/wiki/Rectifier

About half way down is what I copied below. I wasn't able to copy the diagrams. As stated below, there are two ways to make full wave power supplies. The second one is what chargers use, 2 diodes and transformer with center tap.

Full-wave rectification

A full-wave rectifier converts the whole of the input waveform to one of constant polarity (positive or negative) at its output. Full-wave rectification converts both polarities of the input waveform to DC (direct current), and yields a higher mean output voltage. Two diodes and a center tapped transformer, or four diodes in a bridge configuration and any AC source (including a transformer without center tap), are needed.[2] Single semiconductor diodes, double diodes with common cathode or common anode, and four-diode bridges, are manufactured as single components.


Graetz bridge rectifier: a full-wave rectifier using 4 diodes.For single-phase AC, if the transformer is center-tapped, then two diodes back-to-back (cathode-to-cathode or anode-to-anode, depending upon output polarity required) can form a full-wave rectifier. Twice as many turns are required on the transformer secondary to obtain the same output voltage than for a bridge rectifier, but the power rating is unchanged.


Full-wave rectifier using a center tap transformer and 2 diodes.
Full wave power supply

 

[old]

Have not looked yet but I did see numbers on the diodes so I know I can use the numbers to then cross over to one they may have or be able to get
 

[old]

Geo, yes I do understand a good bit about electronics I have forgotten a good bit more then many people ever did learn about electronics. But then I was a Navy E.T. and did computer repair many years ago. I learned to hate electronics over the year. Still remember an odd thing happening when I was playing with a short wave radio and heard a broadcast of JFK getting shoot but what makes it odd is that it was years after the fact but it seemed to be one from the day it happened.
 

[fixerupper]

Heck a little time with a big hammer and block of hardwood and it'll be back in shape. The dials and gauges aren't broken.LOL The neighbor had one that looked about like that when it met the same fate. They just threw it in the hole and buried it. Jim
 

[pete black]

the old adage applies here: if you can't fix it with a hammer then you have an electrical problem.