Which 48V OnBoard Charger?

[JohnnieB]

Originally Posted by techie1

Please explain "switch-mode chargers use much smaller transformers"

I guess SJ is still getting his beauty rest.

The AC input is rectified to unregulated DC.
The unregulated DC is chopped at a high frequency and fed to the primary of a transformer.
Operating at a higher frequency, the transformer doesn't need as much ferrous material in the core as it would need at 60Hz, so can be physically smaller.
The turns ratio and size of wire in the windings are still roughly the same.
By adding a feedback loop to alter the chop frequency and/or pulse width, you can regulate the output voltage and/or current.

Just about any power supply and/or battery charger that weighs significantly less than a pound per amp of output are variations of this basic design concept.

[techie1]

thanks for the explanation

[yurtle]

Originally Posted by techie1

thanks for the explanation

You may also hear them called "switchers", they pack a lot of power for low weight. Cheaper ones are also not nearly reliable as old "coil and core" (big transformer) types, and when they fail, it's a lot more difficult for a novice to repair than old style chargers.

If you've ever looked at a computer power supply, it's the same thing. They're rated for quite a bit of amperage, yet weigh next to nothing.

I wired this one for use as a cheap bench power supply. This particular one was rated for 14 amps at 3.3 volts, 30 amps at 5 volts, and 12 amps at 12 volts, which would weigh considerably more if it had been a conventional coil and core style power supply.

However, back to the original post, though I haven't researched them, they are probably all switch-mode, to save weight and size. The original poster mentioned it was "high frequency", another dead giveaway.

[scottyb]

In the practical everyday world of golf carts, you just can't beat an old style transformer charger for amperage output and reliability.
Many of these unit which are in use today are up to 30yrs old.
I doubt we will ever say that about the new micro processor types.
Which ever one you use, charge often and charge fully.

[yurtle]

Originally Posted by scottyb

In the practical everyday world of golf carts, you just can't beat an old style transformer charger for amperage output and reliability.
Many of these unit which are in use today are up to 30yrs old.
I doubt we will ever say that about the new micro processor types.
Which ever one you use, charge often and charge fully.

Agreed. My cart has room to mount the old style charger under the seat, but that takes up a lot of room and weighs a lot.

Since this thread is about on-board chargers, I suspect most are switch-mode.

[scottyb]

Chargers really don't like being taken for a ride......There is all the vibration and dirt, not to mention on your micro processor types, they are subject to the same spikes a battery pack has to endure???
I have been told by golf cart engineers that this ultimately shortens their useful life.
I'm leaving my charger at home and planning on getting 30yrs of use out of it.
Plus ~ I can get a 5 stage 48v Stand alone charger with a maintenance mode for just $285 at cartsunlimited.net

[bigstik40]

Techie1: This charger looks very interesting!!! I see you are already using it and I have a question for you. Are you able to use the charger/s directly on your series string of 6 volt batteries all at the same time (I am assuming that your pack is 8 @ 6 volts)??? I'm not sure what they mean by a "bank" of batteries. Couldn't find any connection instructions on the NOCO site. My application would be for 36 volts. Thanks - RAY

[techie1]

Originally Posted by bigstik40

Techie1: This charger looks very interesting!!! I see you are already using it and I have a question for you. Are you able to use the charger/s directly on your series string of 6 volt batteries all at the same time (I am assuming that your pack is 8 @ 6 volts)??? I'm not sure what they mean by a "bank" of batteries. Couldn't find any connection instructions on the NOCO site. My application would be for 36 volts. Thanks - RAY

No, u can only charge 12v per bank
U cannot directly charge 48v by connecting all the banks to 48v 1 pos / 1 neg
U can charge each 2 6v batteries n series hooked to 1 bank (charge wire)

[bigstik40]

Thanks for the reply, TECHIE1!! I was hoping that I could wire this charger in permanently and just plug the "110" in whenever charging was required. I'm waiting for a diagram from "GENIUS" as I also questioned them on this and they said it could be done, but a bit "tricky". I'll keep you advised if something different comes up. - RAY

[techie1]

Originally Posted by bigstik40

Thanks for the reply, TECHIE1!! I was hoping that I could wire this charger in permanently and just plug the "110" in whenever charging was required. I'm waiting for a diagram from "GENIUS" as I also questioned them on this and they said it could be done, but a bit "tricky". I'll keep you advised if something different comes up. - RAY

U can hook 2x6volt series batteries (12 volts) to each bank and therefore charge 8 6 volt batteries. The entire 48 volts will be charged