Charging speed, any conclusions?

[RagingGrandpa]

5 minutes ago, MrRobot said:

how the ewheels / Jia Rui charger does cell balancing if it cuts off all the electricity at the end of the charge?

I own an ewheels-branded Jia Rui 900w 100V 8A charger.

It cuts off once current falls to 400mA.

That's a good thing.

Balancing is occurring during all of the CV phase (when the pack voltage is steady at 100+ V and current is slowly falling), and also after the charger cuts off (to bleed any 'high' cells). More info below:
https://forum.electricunicycle.org/topic/22109-passive-balancing-a-simulation/?tab=comments#comment-361242

[supercurio]

6 hours ago, MrRobot said:

Wait what?? What kind of charger is this... Should I cancel my ewheels quick charger order?? 

It's a charger made from a hacked / re-purposed server PSU, which can be found by the sellers or brands GTKPower, ShenZhen Battis or Shenzhen Foxell.
Not at all a polished, user-friendly product like the well known quick chargers.

The GTK one which Shane uses seems to have an annoying user experience forcing to set the voltage and battery every time it is plugged so I'm exploring other options.
However there are inconsistencies on weight and dimensions in the various listings so I'm trying to get clarification from the sellers, which unfortunately have not been very good at providing timely or accurate replies so far.

I wouldn't consider the Chargery @RagingGrandpa due to its weight or prices, neither being competitive for a Sherman compared to a 9A adjustable + stock 5A charger combined.

For now, I'm waiting before ordering to have  bit more about what I'm about to order, but I expect:

• crappy external appearance: might need some mods to be handled safely in use and tossed in a backpack
• I'll solder my own XT-60 to 2x GX-16 dual pin adapter
• between 1.9 and 2.4kg
• 3000W peak
• 2400W sustained
• adjustable 0-140V
• adjustable 0-15A at max voltage
• more than 20A at 100V
• pretty loud fans most likely, which I hope to replace if suitable

I would only use it for fast charging during very long rides, I think that if it works out that would be the best option for me - but not for most due to all the things that can go wrong with it.

[Shad0z]

Very simple, does the 100.8V 8AMP Gotway charger actually work for the Veteran sherman? 

[div]

Any charger that works with 100.8V Gotway will work with the Sherman.

The only thing to look out for is whether the Shermans charge ports have single or double pins wired. If early batch it is single pin, you will need a split to spread the 8A over the two ports. If double pin you can use the 8A on one port.

It should be possible to confirm by checking if there is continuity between pin 1 and 2, as well as 4 and 5. (careful not to short anything) Some Sherman had a mix of single and double pinned ports.

edit: you're welcome.

Edited September 13, 2021 by div

[Shad0z]

On 9/10/2021 at 10:57 AM, div said:

Any charger that works with 100.8V Gotway will work with the Sherman.

The only thing to look out for is whether the Shermans charge ports have single or double pins wired. If early batch it is single pin, you will need a split to spread the 8A over the two ports. If double pin you can use the 8A on one port.

It should be possible to confirm by checking if there is continuity between pin 1 and 2, as well as 4 and 5. (careful not to short anything) Some Sherman had a mix of single and double pinned ports.

edit: you're welcome.

The charger itself (bought and received it) seems to only have two pins wired up) my sherman is also fairly early in terms of batch, so an educated guess would be that my sherman doesn't have 4 pins wired up per port. So I'd need to get a splitter. 

 

But what's the actual issue with charging at 8AMPs on two pins. What issues does it actually cause? I've charged it like that once already, out of necessity. It it seems fine for now

[Planemo]

48 minutes ago, Shad0z said:

But what's the actual issue with charging at 8AMPs on two pins.

Heat.

Personally I think that 8A on two skinny GX pins is pushing it, but tbf it sounds like you don't know for sure whether your Sherman has linked pins or not. Maybe it does.

And yes, the pins on the charger should also be linked. Although my Sherman came linked, I don't know if the stock charger was linked or not as it sold with my old MSX.

As a belt and braces, on my 6A charger I have not only linked the pins but run a splitter as well. Overkill yes but I was bored and had a spare 5 pin plug anyway

 

[RagingGrandpa]

On 9/23/2021 at 5:48 AM, Shad0z said:

what's the actual issue with charging at 8AMPs on two pins

When you exceed the current rating for the terminal contacts, they get dangerously hot.
"How hot" depends on the resistance of the connection (which varies randomly during each plug-unplug cycle), the duration of the overload, and the ambient environment.
You may get away with 8A thru the 5A-rated contacts for a 2hr charge cycle in a cool shaded location; but maybe not for a 4hr charge cycle in a hot sunny location, especially if the connector isn't seated perfectly.

When overheated, soldered terminals (like our EUCs use) typically desolder themselves. This is bad because you'll have an intermittent, arcing & smoking connection, and then possibly an uninsulated wire bouncing around, either inside the EUC or within the charger cable connector. Luckily, the charger and Sherman charging port are protected from short-circuit faults, so the damage is unlikely to be catastrophic. And of course, you won't be able to use the damaged connector until you repair it.

(Crimp terminals, on the other hand, can weld to eachother, melt their connector shells, or ultimately melt their own metal parts, when overloaded...)

  

On 9/23/2021 at 5:48 AM, Shad0z said:

The charger itself (bought and received it) seems to only have two pins wired up

Where'd you get your charger?

If you purchased from pmbatterychargers.com, it's important to select the option "GX-16 5pin 1+ 2+ and 4- 5- "
(All 900w chargers from ewheels / EUCO / other EUC vendors were already this way)
... but also pretty easy to solder a new GX16-5 connector onto your existing charger if you missed that option.

Edited September 27, 2021 by RagingGrandpa

[Ginger On Wheels]

I just read all the posts in this thread and I just wanna chime in and say I own a Sherman that I got on preorder from ewheels when they first came out. I charge mine with the 8amp ewheels and 5 amp stock chargers all the time, so 13amp total. 

 

Also want to say I got one if those repurposed PSU chargers today and its intimidating. Sounds like a small jet engine and gets louder the higher you crank the amps dial. Charged my Sherman with it as a tester @10amps, no issues. Its an xt60 connection then splits into dual gx16-5 connectors.