PSU - Info

[shirley_hkg]

OK , I suppose you'll take new old stock , not used items .

PSU + postage HK$1,200.00
PSU + CASE + postage @ HK$1,430.00

Paypal & pm me your Shipping address .

[steves1977uk]

Just sent you a PM Shirley

Steve

[shirley_hkg]

Gnomatic hasn't responded yet . Wait him another week and go ..

[Gnomatic]

Sorry shirley, been busy and havent kept up here.

I will send you PM with shipping and PayPal info.

[Gnomatic]

Thank you shirley, payment sent!

[steves1977uk]

Payment sent Shirley.

Steve

[shirley_hkg]

Six hours after checkout , they are coming to my way .

[Gnomatic]

Looking forward to it, shirley!

[shirley_hkg]

Foster home .

[steves1977uk]

Can't wait!

Steve

[Burgerman]

You wont have much choice. Takes ages! Slo boat from china!

[shirley_hkg]

Delivery in 2 or 3 days via Speedpost , postage doubled .

Allow me to test it , before shipping out .

[Gnomatic]

Looking good.

[shirley_hkg]

Parcels are out today .

[Burgerman]

Excellent! Thanks for all your hard work. Now we wait.

[Gnomatic]

Thanks shirley!

[Burgerman]

And then out with the soldering iron. And into the new case with anderson connectors and so on.

So it can charge chairs directly or via the PL8 or whatever.

[steves1977uk]

Thanks Shirley

Steve

[Burgerman]

We will ned a build thread!

[shirley_hkg]

No , you don't need one.
You guys opted the one that they are modified already , @ a .

We will ned a build thread!

[Burgerman]

I meant for swapping case, anderson, fuses, etc.

[shirley_hkg]

Try it on a pair of old MK Gel.

CV @28.2V ,for 9hrs . Current seems won't sag any further .

[Burgerman]

Because they are old...

With older batteries you need to lower charge voltage. The correct voltage at room temperature is 13.8 up to a max of 14.1V. But old batteries are not efficient and warm up as you charge so voltage must be lower. And the older they are the higher this current will be.

To desulfate old batteries as much as possible leave on a small 200mA limit with 15v max for around 3 days. But dont expect miracles!

[snaker]

I bought this 30V PSU. It looks sturdy and high quality.
https://item.taobao.com/item.htm?id=19995041970

I have some questions about this PSU:
1. I see 4 terminals +S, -S, SHARE BUS, ON/OFF in the center. What are they and what do they serve for? If it is unused, should I insulate them or leave them alone.
2. I worry about the non-insulated AC input terminals. Is there any solution to insulate them?

[shirley_hkg]

Hot Glue as insulation .

[snaker]

It seems this PSU was built for Military use. It is truly bulletproof

[Burgerman]

Unless charging at max power, I always choose 24V so that the charger is always in boost mode and doesn't need to swap from buck to boost at any time. But failing that setting it at anything under 30v should be ok.

[Burgerman]

Try it on a pair of old MK Gel.

CV @28.2V ,for 9hrs . Current seems won't sag any further .

Mine do. Yours dont because they are sulfated and old. So set termination or transition to float to occur at .5A instead of .2.
Or set volts to 28.0 instead. Or try to charge at CV for around 8 hours anyway, it might remove some of the sulfates. But watch out as the current can begin to increase. And then the battery gets warmer. Then it draws more Amps... Gets ever more warm, and melts...

[shirley_hkg]

Roger that .

[snaker]

Unless charging at max power, I always choose 24V so that the charger is always in boost mode and doesn't need to swap from buck to boost at any time.

Is the boost job easier and more efficient to PL8 than buck? If the purpose is only to charge a 24v lifepo4 pack at a medium current what input voltage is the best?