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

[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 #.

[electraflyit]

Are the 900w still availible? Can't see them on the BMS site
Eddie

[Indubitably]

So I bought one of these bad boys about a year ago (EMC 2000) and at the time I was using a 68.5v pack, but recently decided to down size to a 24v pack (3.6v * 7 thundersky 40a) to run a geared RC motor system. I've never had any trouble with the charger at the original 68.5v setting, but the moment I adjusted the voltage down to 25v it just sat there like a bump on a log without so much as attempting to charge the battery. I've got one of the newer models that (presumably) tells you what voltage you're at on the panel without needing any fancy resister tricks, so I'm fairly certain I've got the voltage dialed in (I adjusted w4011 until I was in the ballpark of 25v, then adjusted w503 until I hit a steady voltage) but the charger seems to think that I'm already done charging or something no matter what voltage I use (kicks on the fans for a second at start up, but then sits there doing nothing with both the green and red leds on, and reads 0 current no matter how I tweak W401 and W402).

Anyone have any suggestions? I'd like to eventually trick it out to function as a lab power supply for my robot/cnc projects, but for the time being I'd be happy just to see this thing running at about 26v and say 50A (it had a habit of tripping the breaker for anything but the 20a 120v washing machine line at 68v/25a, and I think 50a should be more than fast enough even for thunderskys).

[IBScootn]

How are these working for folks? Might get one for home charging. Wish I could hit it in my e-moto, but looks like two 900w units in parallel is the best i'll be able to.

[Indubitably]

I don't know about the 900w units, but the "2kw" units are pretty heavy. I dare say that you wouldn't want one tagging along for the ride on anything built for performance, even something in the motorcycle or scooter weight class. I suppose it might be worth the sacrifice for the right combo of high torque, and lack of convenient access to anything but 15amp sockets, in a utility vehicle just barely heavy enough to haul it along without noticing much difference in weight. I've been looking at throwing a 6kw RC motor behind a 258:1 winch gear box to create delta-style utility e-trike that may find itself in that awkward middling weight class though, so I'll let you know how it turns out, but I'm kind of doubting that my efficiency is going to be too terribly high considering that those gear teeth don't look like they were machined to a terribly high tolerance.

[heathyoung]

Chargers in that power class usually are pretty heavy - the stock 1.5KW from the vectrix weighs 15kg.

[megacycle]

How much do the case weigh compared to the bare boards?

[Kepler]

Once modded with external adjustable voltage, current and momentary switch for activation without attaching a battery, could you actually use the 1200W or 2000W model as a lab power supply?

I want to bench run and test new controllers and motors without the need to use a battery. Always a bit scary with LiPo and bench testing as if anything goes wrong, the battery just keeps on supplying current until components blow. Using the charger as lab supply would be ideal for this.

[Indubitably]

Mega: Not all that much really, the transformer is obviously your major stumbling block when it comes to weight. I suppose you could make it work with a coreless or aluminum wire transformer if you could find a way to cool it fast enough and were willing to trade volume for weight.

Kepler:

My understanding is that you can in fact use it as a lab power supply with some minor modifications. I'm still trying to adjust the voltage myself though, so I can't honestly vouch for the convenience of such a mod from personal experience.

[megacycle]

I wonder what the difference is between my RSP 3000W im using and ecity 2000W.
The RSP being only 4kg with about 0.5kg of case and bars.

[Doctorbass]

I wonder what the difference is between my RSP 3000W im using and ecity 2000W.
The RSP being only 4kg with about 0.5kg of case and bars.

The RSP case is way much lghter than the ecity extruded aluminum frame!!

Plus they have a true PFC circuit.. not a fake psc like the ecity have

The TRUE PF of the ecity is about 0.75 while the PF of the meanwell is trully corrected with a perfect note of 1.00!

A better PF mean less amp draw on the AC input to give the same amount of DC power at output.

Wich mean the meanwell are alot more efficient.

if only we could play with the current limit of the meanwell RSP serie!.. On the two RSP 1000 i have i removed hald theoutput shunt resistor to cut the current in half and it worked well.. but i wuld preffer finding the right smt resistor to trick with a pot.... I spend hours on that without positive result. the desing is much more complicated

Doc

[megacycle]

I meant to speak more with Fetcher on this, as he was very impressed with the RSP3000 as a lot of people are me included, when i see it pumping 140+A@ 24V+ into pack for a short period on start unreal, i used 6mm2 cable initially, but when the insulation was melting changed out for short 4G , i might push it to see if i can trip its over current soon .
Fetcher indicated a high likelyhood of current control built in to it, the daughter board has additional current tweaking control circuitry which i have honestly, been scared of touching, as it costing me around US$800, but would say well worth it, id say definitely one of my best even purchases.
With the PFC doc yeh drawing 3kW@even say 230V is 13A would be over 17@ 0.75PF, so need this otherwise need bigger than a 15A outlet here in Aus and bigger than 13A on ring in UK.
A couple of these modded for current control Doc, maybe, on your new build doc?

[GCinDC]

Ref EMC 1200

1 = W503 ; turn CW to increase V_out ; range 57V - 116.5V if W4011 set to max V_out
1a = W502 ; is for ??? (not mounted)
2 = W501 ; is for LED lamp indicator adjustment
3 = ?W401? ; is for current adjustment (can't see the label)
4 = W402 ; is also for current adjustment ( probably the fine or coarse)
5 = W4011 ; turn CCW to increase V_out ; shifts the range of W503, kind of offset?; I tried W503 ranges for a number of fixed W4011 positions e.g. 47.0-105.7V, 42.5 - 96.0, 32.5 - 73.5, 28.0 -63.5; I was able to trim down V_out minimum to 2V!
6 = ?
7 = ?

rolf

6 = Display voltage calibration
7 = Display Current calibration

anyone know figure out how exactly to adjust the current, re 3 & 4 above?
is it ok if i up the voltage from 83V to 99 and THEN adjust the current down to match 900W, for the 900W charger?
or should first try to drop the current from 10A to 9A before adjusting up the voltage? I'm planning to use a watts up meter across 4 cells of the 24 to see the amps..

thanks!

[NeilP]

I would wind the current down first, then up the voltage

I added my pic of the internal of my EMC2000 to the wiki

http://www.endless-sphere.com/w/index.p ... MS_Battery