Stacking generic lower amp chargers?

goeielewe

goeielewe

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Jan 16, 2018
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Like these, say ten of them in a case with a couple of fans. Can anyone point out an issue with this?

I was also thinking it'd be neat to take an extra 750w PSU I've got and add a step up controller ran by an Arduino. Thoughts?
 
I've always heard you're not supposed to because the voltage regulators end up fighting with one another. That being said, while I don't recommend it, I stacked ATX computer power supplies +12v rail to increase amps when I was doing cryptocoin mining. They rain for a few months and nothing bad ever happened...
 
Stacking those kind of psus arent that good because they are meant to feed current out and not the other way around. If they all doesnt have the same voltage they will feed each other when no load is applied. And if they don't have any built in protection on the output you can guess the color of the smoke :p

Some of them on other hand can be stacked but not sure of above. I would not do it with any PSU that you arent aware of if the output have blocking diodes.

Also instead of a normal computer psu look for one from a server. They are generally better in terms of output :) They can even be serialized depending on which one you choose to get 48VDC. So basically 4 of those and you will get easy 120A charger :D

But read up before doing such work since it potentially render the ground as a dangerous thing.
 
You can, like the others mentioned. Feedback "could" be an issue. Let's say Charger A outputs 54.4V, and Charger B outputs 53.9V. Charger A will try to push voltage into Charger B if there is no load.
To prevent this, you could always put a schottky diode on the Pos of each charger and that should keep any backfeeding. These would be kinda like the ones used on Solar Panels. But keep in mind, the diode has a forward voltage drop, usually around 1V. So those are rated at 54.6V max output. They would effectively become 53.6V (assuming exactly 1V drop) chargers.

But I'd recommend daromers approach and search for server psu's. They are generally not that expensive overall, considering what they are designed to do. And, they are designed specifically to be paralleled (most of them are) for redundancy.
 
daromer said:
Stacking those kind of psus arent that good because they are meant to feed current out and not the other way around. If they all doesnt have the same voltage they will feed each other when no load is applied. And if they don't have any built in protection on the output you can guess the color of the smoke :p

Some of them on other hand can be stacked but not sure of above. I would not do it with any PSU that you arent aware of if the output have blocking diodes.

Also instead of a normal computer psu look for one from a server. They are generally better in terms of output :) They can even be serialized depending on which one you choose to get 48VDC. So basically 4 of those and you will get easy 120A charger :D

But read up before doing such work since it potentially render the ground as a dangerous thing.
Click to expand...

Sounds dangerous. I'm intrigued by the server PSU idea.

Korishan said:
You can, like the others mentioned. Feedback "could" be an issue. Let's say Charger A outputs 54.4V, and Charger B outputs 53.9V. Charger A will try to push voltage into Charger B if there is no load.
To prevent this, you could always put a schottky diode on the Pos of each charger and that should keep any backfeeding. These would be kinda like the ones used on Solar Panels. But keep in mind, the diode has a forward voltage drop, usually around 1V. So those are rated at 54.6V max output. They would effectively become 53.6V (assuming exactly 1V drop) chargers.

But I'd recommend daromers approach and search for server psu's. They are generally not that expensive overall, considering what they are designed to do. And, they are designed specifically to be paralleled (most of them are) for redundancy.
Click to expand...

So, server PSU's sound like a good choice as I know I can find a few easily. What should I be looking for in a good high amp boost converter?
 
if you need a 48v charger, go for something like the eltek flatpack 2 or a delta esr 48/30d. 48v 40 or 30 amps, no stacking no hassling...
 
.... and you can series connect them, and they talk Canbus, and you can stack them.

Here's one of my 8kW @ 54v DC chargers.


image_hnegxb.jpg
 
Korishan said:
To prevent this, you could always put a schottky diode on the Pos of each charger and that should keep any backfeeding.
Click to expand...
Does this seem adequate?
I really like the idea of having a bank of 10 2-4A chargers. It'd be nice to have a redundant grid charger for sailing in more remote areas where shipping a charger in is expensive and time consuming. Also These little chargers are cheap and mass produced. Let's see if I can do this safely as to not burn my boat down. ;)

Charly144 said:
if you need a 48v charger, go for something like the eltek flatpack 2 or a delta esr 48/30d. 48v 40 or 30 amps, no stacking no hassling...
Click to expand...

Dang, those are exactly the thing I'm looking for! Thanks man

Sean said:
.... and you can series connect them, and they talk Canbus, and you can stack them.

Here's one of my 8kW @ 54v DC chargers.


image_hnegxb.jpg
Click to expand...

You guys are life savers, I had no idea these existed. This is what I need to fast charge.

I've been wondering how I'm goona charge the boat's 9kwh pack docking at a transient well overnight.
 
Yeah, that's one of the schottkys that'll work. It has a reverse voltage of 150V, so it'll handle a lot in case of an accidental sparky. Forward voltage drop is about 0.85V at 25C, so that's pretty good, too.
 
You mean the DB9 connector ?itcomes with the Leonardo kit, it's not soldered on,you just need to get the CAN lines from the board to the charger, via the charger breakout board, or if you want to save 15, solder direct to the pins (which is a complete bodge)
 
DB9 connectors are the most commonly used connector for CAN communications. The other connector is RJ45. But the kits Sean is referring to uses the DB9 (I'm assuming)
 
Fortunately,idohaveflatpackspluscontrolunitsplus19cases...pluspcbsforsale?Ialsodohavesoftwaretocontrolflatpackfrompcwithusb2canmodule.

Whereareyoulocated?
 
Sean said:
You'll likely just need the one 2kW unit for an overnight docked charge, along with a breakout PCB and an Ardunio board with CAN.

http://www.hobbytronics.co.uk/leonardo-canbus?keyword=Canbus

https://www.ebay.co.uk/itm/1x-Eltek...1cbe853723:g:M2YAAOSwq1NZhweV&redirect=mobile
Click to expand...

Can you share the library/sketch? I'm going this route for sure!

Charly144 said:
Fortunately,idohaveflatpackspluscontrolunitsplus19cases...pluspcbsforsale?Ialsodohavesoftwaretocontrolflatpackfrompcwithusb2canmodule.

Whereareyoulocated?
Click to expand...

Detroit MI, PM me.
 
Charly144 said:
Fortunately,idohaveflatpackspluscontrolunitsplus19cases...pluspcbsforsale?Ialsodohavesoftwaretocontrolflatpackfrompcwithusb2canmodule.
Click to expand...

What version of PowerSuite ?
 
I do have fp2, not the HE version. They are revision 1.2

They dont keep their settings, when turned off.
 
Charly144 said:
I do have fp2, not the HE version. They are revision 1.2

They dont keep their settings, when turned off.
Click to expand...

I was asking about what version of the PC software, thats used to configure the 19" rack controller.
 
Ive got powersuite 3.6.2, but have never used it. I made my own pcbs with can adapter...

In future my elteks will be controlled by victron directly
 
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