replacing 58v charger with 48V ?

[Canuckle]

Hi there. I am brand new to the site this evening, and this may be the wrong area to ask this. Apologies . I am not going to pretend I am an electrical person so please bear with me.

My Chinese 58v 2A charger is dead. Having trouble finding replacement as searching online keeps taking me to manufacturers only. I don't need to buy the minimum 100. LOL When I do come across one it is the wrong plug type. Mine is a typical 3 prong female power adapter type.

I metered the SLA battery's and they were putting out about 12.86v each. THe bike (at that moment) was putting out 51.2

What are the safety concerns of using a 48v or 60v charger ? I was skimming through some of the FAQ's and someone mentioned they don't ever go to sleep with the batteries charging and that made me sit up and take notice. haha

Thanks for reading if you made it this far. Any helpful advice appreciated. So far I have service folks shaking their heads or very hesitant about selling me a charger.

 

[Rassy]

Hi Canuckle and welcome to ES. Something seems wrong with your premise that you currently have a 58V charger. If you have 4 12V SLA batteries connected in series that is considered a nominal 48V system and requires a 48V charger, which will actually charge your full pack somewhere between 54 and 55 volts, if I recall correctly. Your old charger may have been capable of 58V but it would not have charged the pack quite that high.

If the wrong connector is on a new charger you should just be able to use the one that is currently on your old charger. Make sure you get the polarity right by double checking with your digital voltage meter. If the connector comes apart you should just be able to attach the new wires there. otherwise, you can splice the wires a few inches from the connector. Did I mention to be sure you get the polarity right. Even if you buy a new charger with the correct connector you need to check the polarity before you plug it into the battery.

 

[Canuckle]

thanks so much ! The old charger says 58v on it which is why I mentioned it. Oddly enough just after I posted this note I did get an email back from a local e-bike supplier who mentioned that a 48v 1.8A charger should be cool to use.

And just to swallow my pride some more, I did try splicing a new plug onto the end and everything seemed cool until I plugged it into the bike. Then a small "pop" sound, then a dead charger. There is shame.....

 

[dogman dan]

Ouch. I killed at least three chargers in the first year doing the same thing. Finally I learned to check with a voltmeter before I put the plug on, AND after.

Looks like you wired it up with the polarity wrong. Fortunately the lower amps lead chargers are pretty inexpensive.

 

[dnmun]

do you have a voltmeter? did you measure the voltage on the output of the charger? what did you connect the charger to on the bike? do you know how to check polarity with the voltmeter?

 

[999zip999]

Plugs and the color of wires mine nothing in the world of ebikes and Italian cars.

 

[e-beach]

thanks so much ! The old charger says 58v on it which is why I mentioned it. Oddly enough just after I posted this note I did get an email back from a local e-bike supplier who mentioned that a 48v 1.8A charger should be cool to use. And just to swallow my pride some more, I did try splicing a new plug onto the end and everything seemed cool until I plugged it into the bike. Then a small "pop" sound, then a dead charger. There is shame.....

Lets see...if new 12v SLA'a can charge to 14.4v each X 4 = 57.6 volts....so yea, 58v could get you to full charge on each SLA.

A pop sound?....sounds like you popped something in the charger.....a fuse maybe? Or perhaps a lead between the output circuit and the cable?...... I think you should unplug it from everything, open it up and look for a fuse or a burnt connection between the output cable (that is the one going to your batteries) and the charging circuit of the charger.

If you can, open your charger and take some pictures and post them here. Let us look at the circuit board top and bottom. Make sure they are clear and in good focus. If it is something simple, maybe we can help you fix it.

 

[dnmun]

if he reversed polarity on the charger he has blown the fuse on the output and the zener across the output. but he doesn't have a voltmeter.

 

[e-beach]

if he reversed polarity on the charger he has blown the fuse on the output and the zener across the output. but he doesn't have a voltmeter.

:lol:

On the other hand there was a time, many moons ago, the we didn't have voltmeters either...

I remember my first one, it was analog and I could not figure out what all the lines and indicators meant.
I still don't know what they all mean. :lol:

Nothing like the wonders of a digital multi-meter.

@Canuckle....Looks like it is time to get a Multi-meter. Do you live near anything like Harbor Freight?
http://www.harborfreight.com/catalogsearch/result?q=meter

 

[Rassy]

You guys are beating up on poor Canuckle unfairly. He said he used his meter on his SLA batteries in his very first post.

Canuckle, let us know how it works out. You should post a picture so dnmun can help guide your repair of the blown charger.

 

[e-beach]

You guys are beating up on poor Canuckle unfairly. He said he used his meter on his SLA batteries in his very first post.

Canuckle, let us know how it works out. You should post a picture so dnmun can help guide your repair of the blown charger.

You are right.....My bad, I didn't look closely enough.

All apologies Canuckle! But I was serious about helping.

@Canuckle....If you want to try to fix it, post some pictures so we can get started.

 

[Canuckle]

wow you folks are passionate !! haha

yeah, first time digital multi-meter user . One of those things I bought on super sale as I figured I should have it for something.

I "thought" I had the polarity right as the charger shows the diagram of which side is + and - for the plug . Both the wires are copper and of course the casing had no discernible marks showing which was which. When I first wired it I was getting a negative reading so I reversed the wires. I am thinking I may have had it right in the first place but used the red and black prongs on the meter wrong.

I am going to pick up a new charger but I will pop open the old one as requested. My first thought was also a fuse had blown . Be cool if I can actually fix the old one and have a spare. (Plus winning back a small amount of points for the man-card.)

 

[dnmun]

you can test the zener with your voltmeter set on the diode scale. but the fuse is blown if it was reversed. the zener too.

 

[dogman dan]

Exactly how I fried several chargers in my first few months, replacing the plugs to match my bikes charge port. I just had to learn to properly use the voltmeter, etc.

Hang in there. You'll get the hang of it.

 

[e-beach]

I am going to pick up a new charger but I will pop open the old one as requested. My first thought was also a fuse had blown . Be cool if I can actually fix the old one and have a spare. (Plus winning back a small amount of points for the man-card.)

A 48 volt charger should do it for you. If properly made it should charge to 57.6v and maybe a bit higher in voltage to accommodate resistance while charging. To be sure about what you are getting , buy one with publishes specs that tells you what you are buying.

I am not advocating any of these chargers or companies, just using them as an example. You can see what you are getting with the published specs.

http://www.batteryspace.com/smartcharger30afor48vleadacid110-240v.aspx
http://www.batterystuff.com/battery-chargers/48-volt/multi-volt-input/jac0891-141.html
http://www.tempestbatteries.com/html/BC-48-3000F.html
http://www.batteryspec.com/cgi-bin/cart.cgi?action=link&product=123

My2¢

 

[dnmun]

nobody is piling on. i just asked him if he had a voltmeter since he said it 'popped' when he plugged it in. i assumed he had reversed the charger leads but since we have no pictures of the charger or any info there is nothing to work from to help him. if it is an alloy charger then there is a zener across the output to short the output when the polarity is reversed. we still don't know if that is what happened and still have no picture of the charger to examine in order to provide any help to him.

but he may have shorted something else or in fact he has not shorted anything and the pop he talked about is just the output caps charging up on the charger. no way to know.

if he has a voltmeter he could be checking these things instead of ordering another charger. we don't know that his charger is dead. there are cheaper sources for chargers too. better chargers.