EMC-2000 charger from ecity (1500 to 2000W)

[Nuts&Volts]

With regard to increasing currrent, I have the 2kW model and I ordered it at 142 volts and 12 amps

As of today it has now done about 10 or more battery charge cycles, each one of about 10Ah back to the battery, This is with it re adjusted to 83 volt and 20amps and it barely gets warm

Neil any idea what the upper voltage limit of your 142V model is? I am thinking of ordering one of these and want to get as much voltage range as I can. My lower charge limit ever will be something like 80V, but down the road I may rebuild my pack to be a higher voltage. Thinking about getting a 1500 or 2000 unit and still trying to decide between 110V and 240V input

[NeilP]

I think that the thumb rule is that they are 3/4 of their model rated power.

but from now nobody seem to have pished them to their lilmit ( 100% of rated power)

They told me the max of 12 amps at 142.8, so 1713W..so the 3/4 is about right...85 % in my case At present I am running at 1660W..so 83%.

Neil any idea what the upper voltage limit of your 142V model is? I am thinking of ordering one of these and want to get as much voltage range as I can. My lower charge limit ever will be something like 80V, but down the road I may rebuild my pack to be a higher voltage. Thinking about getting a 1500 or 2000 unit and still trying to decide between 110V and 240V input

I would love to help you and push mine up all the way for you to see what it can max out at..but no...sorry no keen on popping something. Hey..I know..the price has dropped
you buy me a new one and get it sent my way and I'l push it all the way for you

BTW how come you have a choice of 110 or 240? thought that was decided by your countries mains voltage..where are you ?

[Nuts&Volts]

Neil any idea what the upper voltage limit of your 142V model is? I am thinking of ordering one of these and want to get as much voltage range as I can. My lower charge limit ever will be something like 80V, but down the road I may rebuild my pack to be a higher voltage. Thinking about getting a 1500 or 2000 unit and still trying to decide between 110V and 240V input

I would love to help you and push mine up all the way for you to see what it can max out at..but no...sorry no keen on popping something. Hey..I know..the price has dropped
you buy me a new one and get it sent my way and I'l push it all the way for you

BTW how come you have a choice of 110 or 240? thought that was decided by your countries mains voltage..where are you ?

Haha no I wouldn't ask you to push it too far. I am thinking that I should order for 10% less than the max voltage i want to run it on. say 40s or 166V, so order a 150V and tune it down to 88V for now. But then my current is quite limited

Another option. What is the thought on running one of these in series with another power supply? Using this guy as the current limiting device, like people do with meanwells. I would be doing this to get more voltage and power I can then get a higher current lower voltage model. Then just add more PSU for higher voltage needs. Especially if I can adjust the charger over a 40V range

I'm in the US. My parents have a 220V 50A we installed into the garage, the line used to run a hot tub. I may also be able to get a 220V line at my apartment at school, but 110V would be a safer beat for that and if I ever need it on the road. Maybe I should just get a 220V model and buy a transformer for my apartment??

[NeilP]

Haha no I wouldn't ask you to push it too far. I am thinking that I should order for 10% less than the max voltage i want to run it on. say 40s or 166V, so order a 150V and tune it down to 88V for now. But then my current is quite limited

Another option. What is the thought on running one of these in series with another power supply? Using this guy as the current limiting device, like people do with meanwells. I would be doing this to get more voltage and power I can then get a higher current lower voltage model. Then just add more PSU for higher voltage needs. Especially if I can adjust the charger over a 40V range

I'm in the US. My parents have a 220V 50A we installed into the garage, the line used to run a hot tub. I may also be able to get a 220V line at my apartment at school, but 110V would be a safer beat for that and if I ever need it on the road. Maybe I should just get a 220V model and buy a transformer for my apartment??

Depending on what other PSU you are thinking of, if you are like me and try and be as cheap as possible where possible, then finding another PSU that will push enough amps will be more of an issue. If you were thinking of 20 amps or so, then OLD PC psu's or better still server PSU's can put out good amps ut at low voltage. Standard PC PSU's (350-550W) are often good for 20-25 amps on the 5 volt line..but then you need a hell of a string of them to get the extra voltage..but if you just need 10 or 15 volts extra at 20 amps or so, then that could be the way to go.

Oh yea, I keep forgetting about the USA '220volt" still not quite got my head around it..I think it it basically a 2 phase supply right?

I have taken my charger down 60 volts...83 now from my order of 142.8.
I think you are better going for a higher range rather than a lower range than you need. Simply because..if you go lower you may then end up with a supply built up with lower voltage caps etc...so you take it up and you may have to start up-rating other components

[Nuts&Volts]

Depending on what other PSU you are thinking of, if you are like me and try and be as cheap as possible where possible, then finding another PSU that will push enough amps will be more of an issue. If you were thinking of 20 amps or so, then OLD PC psu's or better still server PSU's can put out good amps ut at low voltage. Standard PC PSU's (350-550W) are often good for 20-25 amps on the 5 volt line..but then you need a hell of a string of them to get the extra voltage..but if you just need 10 or 15 volts extra at 20 amps or so, then that could be the way to go.

Oh yea, I keep forgetting about the USA '220volt" still not quite got my head around it..I think it it basically a 2 phase supply right?

I have taken my charger down 60 volts...83 now from my order of 142.8.
I think you are better going for a higher range rather than a lower range than you need. Simply because..if you go lower you may then end up with a supply built up with lower voltage caps etc...so you take it up and you may have to start up-rating other components

I actually already have two of these bad boys which current limit by themselves, but I can't adjust the voltage below 48V easily and I feel like I may be stressing it by making it limit down 8V or so when charging. I also don't get a constant voltage range and those have to manual disconnect when charging.
http://www.ebay.com/itm/NEW-Cherokee-In ... 0847005833 (I unfortunately paid $150 each a year ago..)

I suppose I could spend a little bit more time trying to trim the voltage on the Cherokee, I have just been so busy with other things and got lazy . According to this post http://endless-sphere.com/forums/viewtopic.php?f=14&t=26039&hilit=cherokee+psu&start=15#p384738 I should be able to get down to 41V. If I can't easily do it I will get one of these EMC chargers to get proper voltage limits.

Oh and the 220V works by switching between 2 110V lines and ignoring the neutral line. The two "hot" lines are then run out of phase (110V+, and 110V-) which gives you 220V effective (i think). Everything should have been wired like this because you can still get 110V between one line and neutral, but I wasnt around when all this was created.

[Indubitably]

Damn, I was planning to string a bunch of current adjustable hobby king RC power supplies together to get something that I could scale down depending on the reliability of available power outlets, but if this can do the same thing for cheaper with half the headache I'm set. It looks like the 2kw model will fit perfectly in my battery box for that matter too (with some minor upgrades to the ventilation system of course).

[999zip999]

So is the 900w just a 700w or so. And what's the biggest difference between the 1200w model ? Does it have the read out on the front.

[heathyoung]

Can anyone confirm that the small power transformer is just running the fans? Or is it being used for the bias supply as well?

Very tempting to get one of these at this price and modify it.

[NeilP]

Dont think any of us have reversed a schematic for one yet...Looks like you got your self a job

[sn0wchyld]

ok so before I go playing with my only bulk charger, I want to ask if changing the 'cuttoff' voltage pot also changes the voltage display on the LCD (without a battery connected)? I've got the 900W model. Just don't want to pull it apart for what seems a quck and simple change if I actually need to find a different point in the charger to test what my new cuttoff voltage will be...

cheers all.

[Science Faction]

Hyena organised 3 1200W BMS battery chargers for myself and 2 friends I built bikes for.
We had them set to 76V for the 18S2P packs we run.
They charge at 13A, so 988W.
I adjusted pot number 2, as indicated in NeilP's post on page 5, so the indicator was showing 25V to see if I could charge a 6S 8AH Nanotech.
When I plugged it in nothing happened.
Is there another pot that needs adjusting?
Or is this just outside of limits?
Or do I have to bridge the relay as Doc describes?
I have since turned pot 2 up and taken the voltage on the display up to 76.7V and it works fine.
The combined 3 cellog readings added upto 76.68V, so it's pretty spot on.
I found using pot 2 alone i couldn't raise the voltage above 78V.
I will try using pot 5 as well and see if I can get the voltage up any higher.
I would like to be able to charge 24S as well.
If I do take the voltage up for 24S I will want to drop the current down to 9.75A to maintain that 988W peak.
Thanks to Doc and NEilP I know which pots to turn, however how do I make the current measurement safely without plugging it in to the 24S pack and potentially overloading?
Hang on, I figured it out myself.
I can connect my 18S pack at 76V and I will be able to turn the current pot and while in constant current see the Amp displaying dropping.
Hooroo

[Science Faction]

Ok so I tried adjusting pot 5 by NeilP's post on page 5 and the highest voltage I could get was 80.4V.
While feeding 13A into an 18S pack I was able to reduce the current to 9.7A using pot 4.
I started to turn it back up again but the voltage had reached 76.6 so the current was starting to drop.
So i am flattening the battery pack a little to give time to adjust, I am going to take it upto 13.5A and see how it goes.
I will try to see if I can turn down the voltage to do 12S 50V and then I can split my 24S pack and charge them or otherwise I am going to order the 900W charger set for 24S.
Cheers

[NeilP]

Can't check mine to see right now. i am at work. may make it home tonight not sure..when ever I get a call out, I never knwo what is going to happen

[zombiess]

Hyena organised 3 1200W BMS battery chargers for myself and 2 friends I built bikes for.
We had them set to 76V for the 18S2P packs we run.
They charge at 13A, so 988W.

Sounds like you are pushing the charger pretty hard, does it heat up much or give you any concern with how hard you are pushing it? When I talked to BMSBattery I asked them what I could adjust my 1200W to and they said not to exceed 125V 6A (750W) which is where I have it. I ordered it at 125V 5A.

[sn0wchyld]

Hyena organised 3 1200W BMS battery chargers for myself and 2 friends I built bikes for.
We had them set to 76V for the 18S2P packs we run.
They charge at 13A, so 988W.

Sounds like you are pushing the charger pretty hard, does it heat up much or give you any concern with how hard you are pushing it? When I talked to BMSBattery I asked them what I could adjust my 1200W to and they said not to exceed 125V 6A (750W) which is where I have it. I ordered it at 125V 5A.

What?!!?! my 900w unit is set to 100v 8.2A from the factory, or about 800W, and has been going strong for nearly a year. no visable heat damage on any internals (darkening of wires etc), and the fan only runs about 50% of the time on a hot day.

My 240w unit, however, which was set for 1.5A/100v, smoked itself on its first charge. so now I'm building my own.

[Science Faction]

"Sounds like you are pushing the charger pretty hard, does it heat up much or give you any concern with how hard you are pushing it? When I talked to BMSBattery I asked them what I could adjust my 1200W to and they said not to exceed 125V 6A (750W) which is where I have it. I ordered it at 125V 5A.

That's how it came, 76V and 13A, the fan comes on after a few minutes and stays on, but the air coming out isn't hot.
No weird noises.

[Science Faction]

What?!!?! my 900w unit is set to 100v 8.2A from the factory, or about 800W, and has been going strong for nearly a year. no visable heat damage on any internals (darkening of wires etc), and the fan only runs about 50% of the time on a hot day.

Have you tried adjusting the voltage down on your 900W unit?
Do you know if it will charge at 76V?
I am keen to order the 100V 8.2A and the set up a switch like Miuan to go to 18S 76V.
Cheers
Paul

[methods]

We (Matthew really) landed a couple of the 2KW units and ran some tests yesterday.

100.8V
~15A
~1.5KW DC charge Power

We were seeing about ~16.5A on the AC line which (here) runs about 120V.
Blew a 20A breaker once with a Shop Light running on the same circuit - but after turning that off we were good to go for a 20Ah charge

Fans are stout - only come on when things get hot and heavy and blow a ton of air.

These BMS chargers pretty much kick ass.... Shipping is a killer but value is great. The Volt/Amp readings are definitely close enough to be useful.

If I had to find something to complain about - the handle is made from a yellowish plastic that screams CHEAP to me.
But of course that means nothing.

We have been impressed with the Value on the 900W units and the power of the 2KW units. If we can just get them to lower shipping costs in quantity we will buy them all

-methods

[megacycle]

so now I'm building my own.

What ya building snow

[Science Faction]

I will try to see if I can turn down the voltage to do 12S 50V and then I can split my 24S pack and charge them or otherwise I am going to order the 900W charger set for 24S.
Cheers

I adjusted pot 2 down to 50.7V and it works.
So I just need to make a parallel harness and I can charge 12s 2p.
I left the current at 13.5 A, however I will try taking it up in 1 amp increments to 19.5A for an equivalent power output.
Just waiting on 2 150w discharge battery medics to get it all balanced.
Not sure if the 150W discharge will balance quicker or if it is just for discharging from the main leads.
Hooroo

[sn0wchyld]

so now I'm building my own.

What ya building snow

a ccvs charger... should be good for about 200w or so. the 24V ps's im using are 'rated' at 3A, but I dont think they'd do that reliably. 2A should be enough for something that'll easily fit in a backpack.

Basically I'm using 4 24v ps's in series, with the final one using a ccvs buck converter to control the power output. all up it should be less than $50, and be fairly robust. im currently trying to integrate some BM's to for a portable 24s balance charger!

[megacycle]

Was thinking you had a badboy design happening for a sec, till you said lipo.
Looking for a basic BMS for the 60-80A this 3kW meanwell is pumping into these A123 sacks i got,meanwhile i'm manaually doing balancing, experimenting burning fingers on 10W resistors and shuffling supercaps around, in between changing the setup from series to parallel shunting them.
Was hoping to touch base with local lads in Adelaide and surrounds.

[sn0wchyld]

Was thinking you had a badboy design happening for a sec, till you said lipo.

huh? not sure what ya mean by that... but yea, it is for lipo.

Looking for a basic BMS for the 60-80A this 3kW meanwell is pumping into these A123 sacks i got,meanwhile i'm manaually doing balancing, experimenting burning fingers on 10W resistors and shuffling supercaps around, in between changing the setup from series to parallel shunting them.
Was hoping to touch base with local lads in Adelaide and surrounds.

Keen as mate. I've been meaning to meet up with a few other locals for ages but I keep getting snowed under with uni and the rest of life's demands (also known as a girlfriend )...

[megacycle]

Badboy = rectified 240V little more than a few components to give serious and dangerous kW kick arse charging .
Want to do build when Hyenas 5404 & 4060 rock up this week and catch up for a burn and a pint soon .

[sn0wchyld]

Badboy = rectified 240V little more than a few components to give serious and dangerous kW kick arse charging .
Want to do build when Hyenas 5404 & 4060 rock up this week and catch up for a burn and a pint soon .

ah gotcha! yea I have thought about it... something like a hairdryer or similar to controll the power... but I think the gap from 240 to 100 is a bit harder to manage than our USA pals using 110V.

My one's more about walk away reliability, so I could plug this thing in at uni/gf's house etc and leave it for a couple of hours to charge. Hell, if it works well enough, It'd be easy enough to build a 2nd or 3rd in parallel, or I could use higher power PS's to begin with.

Sounds like a plan mate. Ill shoot you a pm with my #.