DIY 'Chargenectifier'

[silverstone]

So I bought a thing (or a few things)

1. Eltek 48V/2000W rectifier for a steal of $50 from ebay
PCB interface board for $12 from ebay
vk4ghz Eltek Monitor to control it for $90+21 AUD (so around $78 USD)

My generator is only rated at 3500W continuous. I think a 48V/3000W would have been a better match, but it was going to cost about 3-4x as much. Though, if I stack 2000W units, I need another interface board and controller to run it.... hm. Maybe I should have done that after all, may have been cheaper. Oh well.

Either way, this will give me the ability to push around 35A into my battery packs from the generator.

Really, this is only for backup of a backup use case, if grid goes down and stays down for any length of time, and the solar sucks, and I need a boost.

.... Or maybe just an excuse to tinker.

The vk4ghz monitor just makes my life a little easier because I'm no programmer and having to buy an arduino and program it myself and all is just not for me right now.

It seems more expensive than what I / @upnorthandpersonal use .

Emerson Charger 48V 3000W around 80-85 EUR each with interface PCB included (you MUST contact Seller prior to ordering and remind them that you want the CAN Pads exposed, i.e. the "old Style PCB"): https://www.aliexpress.com/item/1005003755306962.html






Plus around 15-20 EUR for the CANAble Pro Adapter: https://www.aliexpress.com/item/1005004972158302.html

 

[SparkyJJO]

I have never bought anything from Aliexpress.
3000W would be a better match but oh well.
I could have used something else for controlling the unit but this should work and has a fancy display that while unnecessary adds a little nice feature, and it is already programmed to control it so no messing with CAN signals and stuff I don't want to have to deal with.

 

[upnorthandpersonal]

This is why I like DIY so much: everyone has their own set of requirements, goals, and way of thinking which leads to a multitude of different solutions to problems, for others to build and expand upon.

 

[silverstone]

This is why I like DIY so much: everyone has their own set of requirements, goals, and way of thinking which leads to a multitude of different solutions to problems, for others to build and expand upon.

I've seen worse requirements at full-time jobs trust me .

Anyways I really have to hurry up finding a new Job now .

 

[crossy]

Anyways I really have to hurry up finding a new Job now .

Yeah, I'm in that boat too.

I'm on a project in Cairo (Metro Line 4), I "started" in February and the Contractor (Thales) are now talking about an "initial" meeting with them mid-May!

No wonder it took them 2,000 years to build the pyramids (the site-office has views of the pyramids to remind them to hurry up).

I'm really getting far to used to the 7-day weekends, I may actually have to retire.

 

[SparkyJJO]

Another piece arrived. Fits the back of the flatpack nicely.
I would love to fab a nice enclosure for it, but I have no skills or tools to do so, so it will likely live bolted to the side of my battery shelf in some form or another.




Now just waiting for the control board/display.

 

[SparkyJJO]

Oh guess what, that showed up today.
Now when do I commission it? No idea lol.

 

[wandows]

It seems more expensive than what I / @upnorthandpersonal use .

Emerson Charger 48V 3000W around 80-85 EUR each with interface PCB included (you MUST contact Seller prior to ordering and remind them that you want the CAN Pads exposed, i.e. the "old Style PCB"): https://www.aliexpress.com/item/1005003755306962.html

View attachment 208966


View attachment 208968

Plus around 15-20 EUR for the CANAble Pro Adapter: https://www.aliexpress.com/item/1005004972158302.html

View attachment 208967

It seems more expensive than what I / @upnorthandpersonal use .

Emerson Charger 48V 3000W around 80-85 EUR each with interface PCB included (you MUST contact Seller prior to ordering and remind them that you want the CAN Pads exposed, i.e. the "old Style PCB"): https://www.aliexpress.com/item/1005003755306962.html

View attachment 208966


View attachment 208968

Plus around 15-20 EUR for the CANAble Pro Adapter: https://www.aliexpress.com/item/1005004972158302.html

View attachment 208967

Hello everyone!

Can this CANAble Pro Adapter also be used for FlatPack2?

 

[upnorthandpersonal]

Can this CANAble Pro Adapter also be used for FlatPack2?

Yes, you just need the right protocol for the FlatPack2. There are several sources on github etc.

 

[wandows]

Yes, you just need the right protocol for the FlatPack2. There are several sources on github etc.

Thank you very much for your attention!
This item in the link below is an updated version, will it work as well?

https://a.aliexpress.com/_mMJckx2

 

[upnorthandpersonal]

Should do just fine.

 

[Consumerbot3418]

I've been meaning to start a thread for this. Maybe I will someday. For now, though...

I've got a pair of these Eltek FP2 HE 2000W units set up, and working fantastic! I already use Home Assistant to manage power in my off-grid home, so this ESPHome YAML on Github was a great starting point. I made a few changes to auto-detect the serial number, and support a 2nd unit. Then I got a Home Assistant automation to update the charge current according to PV production.

What's great about this setup is that even if the Home Assistant server is down/gone, the ESP32 has its own webpage where you can set charging voltage/current and monitor input/output voltage, power, and temperatures. Tied to Home Assistant, though, that data is recorded and can even be charted:



I initially only planned to use these as way to connect to grid to avoid worrying about complete battery depletion (without having to get permission from the utility to connect an inverter/charger), but they've ended up coming in very handy--I've been using them daily, since I can't seem to get the XW Pro's charger to work without go haywire.

I had quite a bit of trouble getting CAN working, so I'll try to remember to share a few good photos to show how I got working. Someday, I may try to set up an automatic charge profile for LFP, maybe even other chemistries.

All in, for 4000W (71A at 56V), it was:
$45 x 2 FP2s
$12 x 2 for the PCB adapters
$7 for the ESP32
$9 for the CAN board

So about $130 total.

The vk4ghz monitor just makes my life a little easier because I'm no programmer and having to buy an arduino and program it myself and all is just not for me right now.

I didn't even know these existed... Pretty cool! I was actually considering trying to put together a kit like that (display/interface), and wondered if there might be a market for it.

 

[wandows]

Should do just fine.

Hello friend!
Can you clarify a question for me? I have two Flatpack 2 rectifiers, 48/3000 HE, black front panel, and I would like to know if it would be possible to connect these two sources in series to have a symmetrical source?

 

[zanydroid]

Hello friend!
Can you clarify a question for me? I have two Flatpack 2 rectifiers, 48/3000 HE, black front panel, and I would like to know if it would be possible to connect these two sources in series to have a symmetrical source?

You mean in parallel? Do you have the data sheet/manual handy for us to have a look?

 

[wandows]

Should do just fine.

Hello!
the connection would be in series and not in parallel.
+Vcc GND -VCC

 

[zanydroid]

If they are floating power supplies relative to ground, then you have a good shot.

DC/DC isolated supplies in series for higher voltage?

Can I chain two isolated DC/DC supplies together for a higher output voltage? (Say, a 48V and a 12V to get 60V?) They'd be fed from the same 24V DC source. I've asked a related question before (...

electronics.stackexchange.com

 

[wandows]

You mean in parallel? Do you have the data sheet/manual handy for us to have a look?

it would be more or less like this

 

[zanydroid]

it would be more or less like this

I posted a reference to a discussion about series wiring.

What is the use case? You have a HV battery pack or e mobility battery pack to charge? You might consider also asking on a forum for the specific use case

 

[wandows]

I posted a reference to a discussion about series wiring.

What is the use case? You have a HV battery pack or e mobility battery pack to charge? You might consider also asking on a forum for the specific use case

I have a HV battery and electric mobility batteries, but I asked this question because I was thinking about the many different possibilities of using this rectifier. For example: an audio amplifier that requires a symmetrical source, using two rectifiers in series (as shown in the figure above).

 

[zanydroid]

I have a HV battery and electric mobility batteries, but I asked this question because I was thinking about the many different possibilities of using this rectifier. For example: an audio amplifier that requires a symmetrical source, using two rectifiers in series (as shown in the figure above).

So far I’m thinking output protection (like reverse polarity and isolation), and floating outputs relative to chassis ground, are necessary but probably not sufficient.

There are likely other things to consider like what happens to the load if one leg turns on slower or not at all, which a single power supply maybe smarter at preventing.

 

[wandows]

So far I’m thinking output protection (like reverse polarity and isolation), and floating outputs relative to chassis ground, are necessary but probably not sufficient.

There are likely other things to consider like what happens to the load if one leg turns on slower or not at all, which a single power supply maybe smarter at preventing.

 

[wandows]

I have two units of the XY6020L Step Down (I bought it on AliExpress), I'm going to take the opportunity to do some tests with a symmetrical configuration. I'll show the results here later!

 

[wandows]

I have two units of the XY6020L Step Down (I bought it on AliExpress), I'm going to take the opportunity to do some tests with a symmetrical configuration. I'll show the results here later!

Hello everyone!
Today I was able to do a quick test with two FlatPack2 3000 HE rectifiers in series with two XY6020L dcdc, forming a symmetrical source (+ GND -).
The rectifier worked normally without any instability, so I can say that the rectifier can be used in series.
On the day I am not working at the company I will post photos and videos.

 

[42OhmsPA]

Over a year later finally got around to ordering one of the Emersons.
$89.51 with shipping and tax.
Should be here in a couple weeks.

Went with the 57V pre-programmed.
Plan to use it for a 'quick charge' of 690Ah of cells I'm picking up Sunday before top balancing. Now to find the best price on more JBDs.

Here's the link I used, the one I had in my cart said no longer available, I panicked for a second, but the seller must have made a new listing.

I noticed a familiar looking photo in one of the reviews. .

Just found this amazing item on AliExpress. Check it out!
$49.82 | Emerson R48-3000e3 Communication Switching Power Supply Module 48V Induction Heater Power Supply Disassemble With interface

https://a.aliexpress.com/_mr73c18

I'll regret not ordering 2 of the them about 30 minutes in to charging

I finally got around to using it....
The 57V version does ~40A on the DC side happily.

It took about 10 minutes for me to regret not ordering 2...

Note - wires were upgrading shortly after taking the photo, 16AWG makes a nice heater...

 

[silverstone]

I finally got around to using it....
The 57V version does ~40A on the DC side happily.

It took about 10 minutes for me to regret not ordering 2...

Note - wires were upgrading shortly after taking the photo, 16AWG makes a nice heater...

16AWG is less than 1.5mm2, I wouldn't put 10A on it, let alone 40A.

6mm2 for 40A is a gamble (depending if PVC/XLPE Insulation and Installation Conditions among other Things), I would just take 10mm2 or, since I never use that size, standardize to 16mm2 since that's the next size I commonly use.

So probably AWG8 or AWG7 ...