Rotating diode issue

[mtfleming]

In replacing diode I cut wire too short. I soldered a short piece of wire onto diode to make it reach and have tried numerous times to solder two wires together. It will last for a few days (running generator daily) and then come apart. Is there some type of crimp that will last in that situation without flying off into machine? (This is a MEP002) I wonder if I need a different type of solder. I don't believe the wire is copper.

 

[Guyfang]

What means come apartment? Break? Or separated? If it's separated, I would say it's a cold solder. Cold solder is because you need to use perhaps a different solder paste, and you don't get the solder hot enough. Are you using the same gage wire as the original? I would tell you what type paste I use, but then you would need to come to Germany to get it. I am sure someone else will chime in here. If it were me, I would use a butt connector. And a GOOD crimping tool.

 

[Kenny0]

In replacing diode I cut wire too short. I soldered a short piece of wire onto diode to make it reach and have tried numerous times to solder two wires together. It will last for a few days (running generator daily) and then come apart. Is there some type of crimp that will last in that situation without flying off into machine? (This is a MEP002) I wonder if I need a different type of solder. I don't believe the wire is copper.

The biggest things in soldering are 1. Make sure both pieces to solder are absolutely clean with no oil or grease film what so ever. Use fine sandpaper or fine steel wool. Use a spray type degreaser for oil or grease. 2. Always use a flux. Electronic flux would be the best, I have used paste flux for soldering copper pipe with good success. Do not use an acid flux. Clean excess flux from the joint when you are finished. 3. Use a 60/40 solder which contains lead, this is the easiest. Lead free solder can be used but is harder to use. 4. Use the right amount of heat. Too much heat will destroy the diode, too little will have a cold joint. A properly soldered joint will have a nice taper going to everything soldered. A hump can indicate a cold joint or too much solder. 5. The wires must be twisted around each other for the strongest joint. 6. Experiment soldering on something else before soldering on this. - The wire is probably copper wire with a very thin coating of another metal.

 

[doghead]

What kind of solder are you using?

What kind of wire are you soldering?

What are you using to solder with?

Can you tin either wire?

 

[tennmogger]

Silver solder is stronger than plain tin/lead solder.

 

[GREENMV]

Tinning is a good technique to learn.

What kind of solder are you using?

What kind of wire are you soldering?

What are you using to solder with?

Can you tin either wire?

 

[Guyfang]

I learned to solder from my Vorbild, ah, just a second, it will come to me. Mentor! That's it. I learned from my Mentor, Gilbert Denche. A Frenchman in the US Army. He made me practice, and practice. Nothing was good enough. One day, he stopped complaining. Was a long row to hoe, I tell you. Its almost a forgotten art now. Good tools. Patience. Practice.

 

[mtfleming]

Thanks for the feedback. I checked my solder joint and it is holding. When I start the generator and turn the breaker on sometimes the voltage drops. I can hold the knob on start and reflash the field. Sometimes this will cause the voltage to not fall and it will generate fine. I don't have to continually hold the knob, only reflash the field to get the voltage to stay up. Is this normal?

 

[mtfleming]

I'm using rosin core but I don't know the composition. I tinned both wires and used 150w soldering iron. I soldered the diode with a 30w iron.

 

[Carl_in_NH]

I think the biggest thing missing from the discussion is the mechanical connection between the two wires to be joined. Solder makes a good electrical connection - but not a mechanical connection. It's too weak to be placed under repeated mechanical stress and survive - which is why I mention it when you state the joint failed.

When joining two wire ends with solder, tin each end and form a hook with needle-nosed pliers. Connect the hooks together and make the joint mechanically tight with the needle nose pliers, and then solder.

 

[pjwest03]

One of the better videos of the subject of splicing.

Some very good tips on splicing. At about the 08:00 mark, he shows using an un-insulated butt splice as reinforcement for a solder joint. I like this method for solid core wire particularly.

https://www.youtube.com/watch?v=aoD2aUvnQXg

 

[pjwest03]

The other must have for these things is glue lined, marine, heat shrink tubing. It's lined with hot melt glue. It provides reinforcement for the joint and the glue also seals up imperfections fabulously.

 

[Guyfang]

The other must have for these things is glue lined, marine, heat shrink tubing. It's lined with hot melt glue. It provides reinforcement for the joint and the glue also seals up imperfections fabulously.

View attachment 700281

In my line of work, Photovoltaik Power, Biogas Power Plants, Underground power cable repair, Crane repair and what all else I cant remember, that's all we use for cable joining, of any type. After connecting the wires, (butt connectors pressed with a hydraulic crimping device) we use heat shrink to seal it up. I have never, ever, in the last 25 years of using QUALITY heat shrink, EVER had a failure of the heat shrink to keep out moisture. I once joined 21 cables, for a Biogas Power Plant that were run through a liquid pig crap tank. Some cables as big around as 15 centimeters. They are still in perfect shape, and that was in 2010. Simply a GREAT product!!

There is also a type of cable sealing process that uses a Clamped Shell, to go around the repaired cable. The shell is then filled, (injected) with a resin/epoxy that is also 100% reliable, as long as you follow directions. You just don't want to get the crap on you!! I wish I could explain this better, but I just do now know what the english words are for this stuff.

 

[GREENMV]

I had a problem a while back with a 003 unit that wouldn't flash. It would only flash when I held the switch to start, but once I let go it would drop voltage. I replaced S1 switch and A1 Relay upon advice from smarter people than myself on here and it solved my problem. A1 has diodes on the back. Intermediate flash could be something starting to fail???? I once stayed at a Holiday Inn Express.

Thanks for the feedback. I checked my solder joint and it is holding. When I start the generator and turn the breaker on sometimes the voltage drops. I can hold the knob on start and reflash the field. Sometimes this will cause the voltage to not fall and it will generate fine. I don't have to continually hold the knob, only reflash the field to get the voltage to stay up. Is this normal?

 

[Chainbreaker]

Some very good tips on splicing. At about the 08:00 mark, he shows using an un-insulated butt splice as reinforcement for a solder joint. I like this method for solid core wire particularly.

For the "T" splice he did I like to use liquid electrical tape to insulate with since you can't use heat shrink tubing in that configuration.

 

[Triple Jim]

Very true with a T, but a good alternative with self-sealing shrink tube is this. You squeeze between the two wires with long nose pliers and hold until the adhesive sets:

 

[Guyfang]

We also use one that has 4 or 5 sleeves coming out of one large opening. It looks like a glove. We use it on cable ends, coming from underground into a distribution box. To make the main cable watertight. The cable tend to soak up water at the ends. When you slip the thing on and heat it up, it will never be a problem again.

 

[GREENMV]

Multi wire or butt connectors. I have been using this style for years.

https://www.youtube.com/watch?time_continue=1&v=Pn2MsfG3tWc

 

[mtfleming]

Thanks

 

[Floridianson]

I am sure someone else will chime in here. If it were me, I would use a butt connector. And a GOOD crimping tool.

I hate crimping connectors. Sorry sad but true. Solder, liquid tape, heat shrink!