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

[Doctorbass]

Doc
In this picture you show the wires coming in for voltage sense...where exactly do they go on the board..My charger arrived today, and want to start modding it.

Also, the pot for current limiting..is it just wired with two wires?
My pots are covered in white silicon, so i can't see the labels on the board for W104 etc...could you maybe make a drawing or indicate on the picture for me with them labelled

Another thing..do you have a part number or spec for that three pin diode you used for output protection? I have my charger set from fctory to 142.8 volt 12 amps...but want to take it down to 100volt..maybe 84

I finally connected the sense wire to my cycle analyst display so they are no more used to feedback the voltage... it was a pain to make it work with the relay that cut the power and the pwm controller that was trying to bring the voltage back to the setpoint while... the output relay disconnected the output...

I will take a look for the 4 pin diode... it is a 40A 100V if i remember correctly.

Doc

[megacycle]

Hey Doc luv your work.
What do you reckon the approx weight of the boards are
Want to run 3 of the chargers on the go to charge my A123 20Ah's.
The cards are often so much lighter without the case, i'll do an aluminium case

[NeilP]

Hey Mega...you want three of these boards! a 6kW portable charger on the bike!!. How long are you looking for a re-charge? 10 -15 minutes from full discharge?


Doc...

I wound mine down to 84 volts OK this morning, and the battery came up to full charge..it seemed to , current went down and I am sure I heard a relay click out, but both LEDs' stay red, and the ammeter shows a negative value. Do I need to adjust one of the other pots to change the Green LED on threshold too? when changing voltage?

Also, what happens to your supply after you remove the battery and also remove the mains input supply..Mine pulses on/off for a about 20 seconds before going quiet.

[NeilP]

When I first got it, I thought the front panel switch felt 'wrong'..and it was

This switch


Not sure if it was built with only one nut, or if it dropped off in transit. The side with the nut, has had slot cut int eh switch body, so the nut bolt can't thread to it, so i suspect it only had one any way. I cant find another loose inside the case.

Also the little tabs that hold the switch together were loose and switch internals were just hanging in there. lucky nothing seems to be lost



I e-mailed Judy this morning at BMS about this and already have had a reply..asking to see pictures..I have already repaired the switch as can be see in the pics. I will be adding silicon around the switch to hold it together

[megacycle]

Hey Mega...you want three of these boards! a 6kW portable charger on the bike!!. How long are you looking for a re-charge? 10 -15 minutes from full discharge?

Nearly
Hoping for 2.5C, 3 X 7S, so can charge as 3 phase, the self balancing shunting prototype setup on the packs is coming together, so hopefully can balance cells almost immediately will post on it when its ready.
Often need a 3 phase load at work, so i can test, kill 2 birds with one stone, hopefully not me and the packs

A pic of usual workplace ct chambers.

imagesCALQQL16.jpg (4.07 KiB) Viewed 622 times

.

PS. Bergerac in an ev, i'm a grockle aussie lived in St Sampsons on the 'other island' lol for 5 yrs, miss the nightlife, silver service, duty frees and yes dare say the ex.

[NeilP]

miss the nightlife, silver service, duty frees and yes dare say the ex.

Missed the Guernsey night life ...I'd hate to be where you are now then

[megacycle]

Remembering 60,000 pissheads clinging to a rock? The thinking man's Jersey.
Not allowed out anymore at night anyhow kids ev worshipping etc etc .
Still got the good old rivalry though just bigger islands, Aussies and Kiwis.

Anyhow anyone weighed these boards, 3kg+ ain't gonna cut it. Stated whole weight is 6kg's
Is there still a lot of wasted space, lots of discretes by the looks of photo's.

[NeilP]

NO not many SMD's, Just big transformers and caps

[NeilP]

From Judy at BMS, just to update what doc said earlier about what the pots do

1 :Change LED , red to green. Anti clockwise causes LED to change at lower current. Seems to just be an indicator..does not cut or drop charger in to float mode

2 and 5 : reset voltage

3 and 4 : reset current

6 : set current of indicating board .

7 : set voltage of indicating board .


于 2012-2-24 15:09, Neil Paisnel 写道:

[zombiess]

I need to open up my EMC-1200 I just bought and see if the internals look the same. If not, I'll email Judy and see if she'll tell me the pots to adjust for my own needs. Right now it should be set for 125V@5A.

What do you guys think we should keep as a good safety margin? Don't exceed 66% of the rating? So my 1200W unit shouldn't be set for more than 125V@6.3A/800W total? I'm pretty happy to just leave it alone at 5A for now, haven't even had the chance to test it out yet, been too busy with other stuff.

[dangerzone]

I strongly recommend you to buy one that is like 25% more voltage than you plan on using. Ex if you want 24s lipo, than ask for a charger for a voltage for 30s


The reason is that i ordered one for 100.8V ( 24s lipo) and the max adjustable voltage i have is 105V. If i try to modify the resistor near the pot ( the one that set the max range), it dont want to go over 105V and make a strange szzzz sound indicating that it become instable( not good...).

They call them 2000W but generally, the voltage and current they offer is all product that give around 1500W.. just like mine that they wanted to set to 15A max instead of 20A... I dont care about 120V ac at 20A draw or 240V at 10A draw.. but they seem to not accept seting it for output power over 1500W.

I succeded to boose the current to up to 22A ( diring short time) at 100V... but i dont feel confident about keeping that seting continusly...

Also.. if you want to activate the output without the need of having the voltage of a battery detected, you can just connect a resistor across the relay N-O contact... 1000ohm work well and than the relay activate so you have voltage at the output.

About the max voltage they set for you i thing that the component of all teh version of that charger vary depending of the voltage you want. I think that for a given range of voltage or power, they select components according to that... in other words, i thing they have let say 4 version of charger . one that they cah adjust from 12 to 36V with the capacitor and other parts optimized for that range of voltage and current , another for 36 to 72.. adn another for 72 to 105... , another for 105 to 200... etc... due to the higher number of parallel parts for the high current version etc...

That might be the reason why mine can't go over 105V... maibe the PWM is reaching 100% at that value... so That's why i recommand you to select a voltage little higher than what you plan to use... so by that way you will be able to readjust it to your desired voltage.. and the current limit should not be too affected if you use 25% more..


Doc

Wow, great info Doc..!

I was thinking about buying the 900W version (the EMC-900) to power my nominal 98V Headway battery pack (3x36V20Ah in series/36S2P) yet am still not sure if that would do the job. Cause the real voltage of my full pack is 120V and this EMC-900 seems to max at 120V which makes me doubt could it charge the pack efficiently..? Without the szzzzz sound and any smokes coming out from the charger, of course.

The EMC-900 charger in question is specified as 120V5A, is it really so?

http://www.bmsbattery.com/alloy-shell/28-alloy-shell-900w-lifepo4li-ionlead-acid-battery-ev-charger.html

Any ideas..? I have also noticed the weight of the EMC-900 is 2.5kg and the EMC-2000 is around 6kg. Which seemed a bit strange... Does anyone know what's the real weight of those..? I see they come in the same metal alloy shell and am aware the cables gotta be thicker for 2kW cotinuous but what is the biggest difference that doubles and almost triples the weight of the EMC-2000..? Heat sinks, coolers, fans, cables..?

[NeilP]

Anyone got any idea what the LED no.3 does...the one just behind pot marked '7' in my pic above.
This LED never seems to come on.

[NeilP]

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

[methods]

I set up a spreadsheet comparing nearly every aspect of the various models. After focusing down on the 1.2KW and 900W I found that the 900W was a "better value" in nearly every important category

$ / Watt
Watt / kg
Watt / Volume
% actual output vs rated output

This boils down to the fact that the 900W is "maxing out" its housing while the 1.2kw is under powered for its housing. This large 1.2kw housing takes it out of the running for being "portable".

My impression of the 900W units upon arrival was that they were very much within the realm of "backpackable". They are small and tidy. The voltage and current markings are accurate enough for indication use. The power cord that was supplied was beefy 14G.

They tuned the supply to the 75.6V @ 10A that we requested and even supplied mating Anderson connectors (though they were counterfeit)

We steered away from the 1200W unit because of a few factors

Twice as heavy
Twice as big
Half again more expensive
Power increase was not worth these costs

So in the end we felt that ordering a supply that could fit in a backpack, was light weight, cost effective, and could put out an honest 750W was the best for us and our customers.

If it was for strictly personal use?
I would probably go with the largest that they sell then mod it for more

Anyhow - this was a surprise for us as my gut feeling was that we should get the 1.2KW unit. It is always wise to do a proper cost-benefit analysis because sometimes the results will surprise you. This of course depends on what you value though - and we value portability. If on the other hand what you value is something that is overbuilt - the 1.2KW unit would have won out.

-methods

[Philistine]

Thanks for that info Methods, that is the sort of thing we as punters are unlikely to do (and in my case even consider). I hadn't even realised or considered there was a signficant size difference between the 1200W and the 900W.

On a side note, my 1200W the other day made a loud pop. I accidentally plugged the battery in before turning on the charger (don't know if that was the issue), and the unit made a loud pop inside the unit (like something blowing), but then everything worked fine and it has worked fine since. I should note I have been physically abusing the charger (it gets knocked around in my garage which is very messy and things get moved about constantly).

But it is still working charm, I am going to be interested to open it up. But so far it has worked everyday flawlessly since i got it.

[methods]

It may just be that the main output caps were drained and what you heard was them charging from your pack when it was plugged in - I don't know - as I have not played with these much. That is the same sound you hear when you plug a controller into the pack - POP. Usually accompanied by some burn marks on your connectors.

Lets say worst case you actually blew electrolytic caps - it makes sense that it is still working afterwards. Those act mostly as smoothing caps so the output will still produce your charge power - just a little bit noisier. If you look inside you should see fuzz from the popped caps (if you popped any). The top of the caps are always scored so that they will blow open at that point. Very easy to see. Have a look

Should not be a problem plugging a pack in first IMHO - but again - I have not played with these much yet. "Smart" chargers are always less smart in my opinion than a simple CC/CV supply. Just more to irritate us and go wrong.

-methods

[NeilP]

Methods,what was the reason the 2kW unit did not make it on to your list? Or evdn the 4?

[methods]

I like them, and they were on my personal list - but the purpose of this analysis was to find a charger that we can recommend to our customers for bulk charging their first Hobby City lipo packs. We have had a huge influx of folks trying to take the jump right into 18S2P for their first build - so that is why we have been spending a lot of time looking at these chargers, the Medics for balancing, and my gear for cell level limits. I am tired of telling everyone that I cant suggest a complete system for them because of battery management issues.

Folks generally want something that they can take to work, is affordable, simple (i.e. no DIY), yet affordable. I would prefer more like 1.5KW but the housings were just too heavy. My personal portable charger is 18S @ 17A and that is perfect - but it is sketchy as hell and expensive.

You know me - bigger is better.
Here is what is on my desk right this very moment - an 88S pack - 350V

IMG_20120225_203415.jpg (123.34 KiB) Viewed 419 times

I am being a big puss right now putting off the test..... that is a lot of voltage

-methods

[NeilP]

Is this for a bicycle or a motor bike?

Another thing..did you have a 2kW unit? I asked earlier about the third LED but not had an reply on that. On the 2kW there is a third LED...about an inch back behind the panel in the center. It on flashes on briefly when powering up then goes out. Any ideas what it may be?

Thinking it may be a warning LED or similar..but no definite idea..overheat? reverse polarity (I won't be testing that one out )

[methods]

That is just for testing equipment - it is a mix of 16AH and 5Ah in series.

I do not have a 2kw unit but our 900W unit also has an LED inside.

-methods

[megacycle]

Ordered 1X Meanwell 3000, as specs say it'll do multiphase and its only 4kg in housing.i'll just ask Fechter for limiters.
If its any good just get another one 6 or 7 kg onboard not bad for 5 or 6kw.
Aye bigger is better and with the pfc won't have to worry about popping those little single phase circuits on the fly.

[Doctorbass]

Ordered a Meanwell 3000, as specs say it'll do multiphase and i'll just get Fechter's limiters, and its only 4kg in houseing.
Aye bigger is better and with the pfc won't have to worry about popping those little single phase circuits on the fly.

How much?

And... why not two meanwell 1500 for serie or parallel operation ?.. that would give you wide range between max 36V and 112V


Doc

[megacycle]

How much?

And... why not two meanwell 1500 for serie or parallel operation ?.. that would give you wide range between max 36V and 112V


Doc

A$760+22 WA to SA
http://www.radioandelectronics.com/prod379.htm.
Hope you guys in the US and Canada would probably do a better deal at home.

Presently got a 3x2 cheap brick servers for 3 x 25V@50A and a little 24V@6A top up charger already so 7S was how i was setting up the packs for the server outputs. The mods to the packs i've been busy on will have no electronic balancing, its mechanical, instantaneous balancing and they're being set up with cell logs to monitor.
Also been considering redundancy in setup if i pop a cell and or switch, i could just switch out pack and ride home on 2/3.
So with the 3P7S or 3P8S, presently want to draw around 120A and balance switching in the 15 or 20 mins bulk charge time, though yeh there's always room for improvement and there's scope, " what do you think"? doc.

[megacycle]

I know she's a little pricey but it'll cost me $488.82 all up for 2x 1500W ecity @ 2 x approx 5 kg for say 2 x 1200W, the meanwell is good for 3kW+ its true rated and they've stood the test of time.
Bit extra for mods, but end of day got a lightweight powerfull charging solution.
Like you say doc 2 x 1500 meanies might have been the go, give redundacy too as well as flexibilty, but until the mini pulse chargers solutions have been nutted out in other threads, i dare say it'll have to do for now.
Only concern is that i'll be fast charging 3P and is this ok for the charging/balancing method i'm using?

[NeilP]

Ordered 1X Meanwell 3000,

What is the exact model number of this Meanwell?