ZXD2400 modification guild 3Kw 0-60V 0-50A

[LROBBINS]

I decided on strain relief after I broke one wire (during installation in the fancy case - and yes, it was the wire itself) and spent a lot of time figuring out why the unit had stopped working. If the wires were a few mm longer there'd also be less chance of that, and given that there are different fans on different units there may also be slightly different hookups as well. In any case, it's easy to add strain relief.

[Burgerman]

I wonder if these boards/wires are different sometimes. Mine were adequately long, and pretty solid feeling. Anything is possible with the chinese. Trying to fix a wall wart yesterday. No problem, I can see what the components measure on a good one. I have 2 more exactly the same, bought together. They are just 5v phone USB thingies. Took all 3 apart. Inside, all were completely different! 2 used different wiring colours.The 3rd was totally different design. Consistency isnt something they are good at. Its all about price...

[Gnomatic]

I was charging a chair that had new Leoch LPG-70H batteries in it with my shirley PSU. Set to 28.2V and 10A, charging through the pod. The batteries were's too discharged I don't believe, as withing 5 min the volts had climbed to the 28.2V limit and the amps were starting to drop. The current kept falling, but VERY slowly. About 18hrs later, the current had fallen to 0.19V. At which point I disconnected the charger. These things are slowwww to take current.

[Burgerman]

Because the loom on the chair means the voltage at the charger is correct but its lower at the battery. And because the batteries are crap!

Also those batteries may need it set to say .3A and float at 27V. Because they might never drop to a low enough current. Some dont. Aim for around 8 hours CV.

[Gnomatic]

To compensate for the loom, should I up the voltage on the charger to say 28.4v?

[Burgerman]

No. That doesent work. As the battery becomes charged, the resistance of the long thin charge wires and loom, has less and less affect. The battery will be sat at your higher voltage for many hours once the current falls to a low level. And this higher voltage is where the damage is done.

[Gnomatic]

I see, good to know.

I used the chair again some more and charged, paying attention to how long the charger was at the CV stage before the current fell below .3A. It was 7hrs and change, right about where you guessed. So if using the shirley ZXD PSU in three stage mode I will set the offset to .3A, and float voltage at 27v with these particular batteries..

[Burgerman]

That will work.

It wont always be the same though. The depth of discharge and the battery temperature, and the actual charge rate in amps all make a difference.

Even how long it sits before recharging.

Think about that lead sponge - actually finely ground lead past that fills the grid (the plates are like a grid full of empty spaces). If you discharge say 5Ah fast, it all comes from the surface of the plates, rather than the insides. So CV will be short putting that back.

If you take the same 5Ah out over a long time. Or leave it a day sat with 5Ah missing, then the state of charge equalises across the acid, and across all that lead paste inside the cells grids. So now when you recharge, that charge has to reach the deeper lead past inside the plates. That takes about 10 hours...

Its also the reason your 70Ah battery is "dead" after about 35Ah is removed. All the remaining charge is in the centre of the pasted material. The surface charge has been used up. So if you set of at 8Am, go full speed, you stop in say 10 miles at 5mph (2 hour discharge). If you went say 2 miles, then waited an hour, rinse and repeat, it gives the inner charge time to "recharge" the surface where it meets the acid. So you will get 15 miles range instead... Same happens on recharge. Longer CV needed if discharged slowly, etc. Horrid things lead bricks.

[Gnomatic]

How the hell is anyone supposed to keep up with all that???

Makes lithium seem simple in a way.

[Burgerman]

You cant. You can only guestimate. The settings you have now are about as good as you will get. I just mention it so you understand why it may sometimes be faster, or slower. For no obvous external reason. Yes lithium. Easy! No peukert, and they charge at cc/full power right till 99% full.

[shirley_hkg]

One thing you should be warned of , is the fan noise .

It's not about large current , but small current less than 800ma on the contrary , that the heatsink at the front gets hot .

That happens when PL8 is either on idle , or in balance mode .

[shirley_hkg]

Shirley, are there any more available, modded if possible?

YES .

1, In stock case @HKD $1,270
2, FItted with aluminum case @HKD $1,770

Both are modified and shipping included .

[AlexAGF]

shirley_hkg, reply to a private message please.

[Burgerman]

His inbox may be full. And in hong kong theres rioting etc. So who knows!

Have patience. He will help!

[shirley_hkg]

Good new.

Fancy case with Anderson installed now.

I still need John's help to get it done.

[Burgerman]

how?

[shirley_hkg]

I tried several times to persuade Mr.mod_guy to install an Anderson for us with no luck .

Today , I tried the other way round , by talking the fency case maker to drill holes & cut opening for SB50. …… He says YES !

He need to know the sizes of the 2 holes and the opening , and where they should be.

I have no access to these.

John , would you please post a pic, with relevant information ?

[Burgerman]

I drilled through the anderson connector... Decided where I wanted it to be, then drilled holes.
The opening on the rear I will measure:

The cut out is 19mm deep.
And 35mm long.
It begins, 25.0 up from the bottom of the rear face.

the screw holes in the side, are 7mm from the back edge for screw 1, and 7mm + 19.1mm (26.1mm) for screw 2. And are drilled 4.2mm diameter.
And are countersunk for M4 stainless x 20mm cap (allen) bolts.
Two flat washergoes in between case and anderson. And the bolt is a perfect self tap fit into the anderson.

https://powerwerx.azureedge.net/product ... s-sb50.pdf

[shirley_hkg]

You mean you tap the Anderson shell , instead of using lock nuts ?

No room for nuts ?

Things got complicated then .

[LROBBINS]

I did mine a little differently. My cutout is a little smaller so the "groove" in the Anderson fits into it. I then used just one screw from the side (don't remember if its 4 mm or 5 mm and Rachi's napping right now so I'm not going to check). It sits out a little further, but is securely locked in place even if the screw fell out. The Anderson plastic shell is actually soft and elastic enough that the machine screw can cut its own thread.

[Burgerman]

You mean you tap the Anderson shell , instead of using lock nuts ?

No room for nuts ?

Things got complicated then .

No need for nuts. The M4 bolts tap the plastic easily and perfectly. Use nuts and washers if you want. When they come loose and fall inside you might regret that!

[steves1977uk]

Good new.

Fancy case with Anderson installed now.

I still need John's help to get it done.

I'd buy one if you can get this done Shirley.

Steve

[Gnomatic]

I'd buy one if you can get this done Shirley.

Steve

I might get another as well if it came w/ fancy case + Anderson connector already installed.

[martin007]

One thing you should be warned of , is the fan noise .

Is it possible to dispense with the fan?
The fan noise is not compatible with sleep.
Alternative...

[Gnomatic]

Yes, normal 80mm x 80mm x 25mm quiet pc fans can replace the stock ones in the fancy case. Thats what I did. BM removed the front fan completely in his to reduce noise I believe. And I think LROBBINS used a resistor to 'trick' the psu to thinking a fan was installed after he removed one.

[Burgerman]

Thats what I did. BM removed the front fan completely in his to reduce noise I believe.

Only temporarily to see how much quieter it was, while it was already running. But it wont start up if you remove it frst I am informed. It should if you just add a resistor that is the same value as the fan. Although I am using a resistor lead designed to slow a fan, (ebay) which is in seres, to make it quieter. But I dont have a quiet room, PC and solar inverters etc running 24/7. I am fine with a little fan noise. Others may notice it more. I just dont worry about it! Its almost unheard if you stick the thing under the bed. Mines on the chairs seat...

[LROBBINS]

I installed two very quiet fans that have their own temperature-sensor speed controls (you'll have to hunt for those posts if interested - I'm too lazy to do it for you). I also replaced the front perforated plastic screen with a cloth screen to improve airflow. They are very quiet, though some of the stock units are quieter than others as the mfr. used more than one fan supplier. Cooling is, however, on the marginal side especially for a large LiFePO4 pack that stays an extended time at CV, and it was necessary to adjust the multi-stage temperature/fan settings in the unit's EEPROM so that it can run a little hotter without limiting current. The annoying spot remains, as Shirley noted, the fan operation when in float; you'd expect the fans to stop at such low output, but they don't. With the original fans' "no temp control at float" it was really annoying. With the self-controlled quiet fans much less so.

[shirley_hkg]

I did mine a little differently. My cutout is a little smaller so the "groove" in the Anderson fits into it. I then used just one screw from the side (don't remember if its 4 mm or 5 mm and Rachi's napping right now so I'm not going to check). It sits out a little further, but is securely locked in place even if the screw fell out. The Anderson plastic shell is actually soft and elastic enough that the machine screw can cut its own thread.

Hat's off to a great papa.

It is M4.

No need for nuts. The M4 bolts tap the plastic easily and perfectly. Use nuts and washers if you want. When they come loose and fall inside you might regret that!

Good point .

[shirley_hkg]

Shirley, are there any more available, modded if possible?

YES .

1, In stock case @HKD $1,270
2, FItted with aluminium case @HKD $1,770
3, Fitted with aluminium case & Anderson SB50 @HKD $1,800


ALL are modified and shipping included .

[Irving]

Shirley, are there any more available, modded if possible?

YES .

1, In stock case @HKD $1,270
2, FItted with aluminium case @HKD $1,770
3, Fitted with aluminium case & Anderson SB50 @HKD $1,800


ALL are modified and shipping included .

You have PM...