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

[dnmun]

well actually the transformer can be swapped. it is just impossible to buy another transformer and almost as impossible to unsolder the old one and remove it so just buying another charger is cheaper and easier.

i always use a charger in series with the power supplies to maintain the current control. otherwise if you only use power supplies you have to do the current limiting hack that richard created.

 

[Doctorbass]

i always use a charger in series with the power supplies to maintain the current control. otherwise if you only use power supplies you have to do the current limiting hack that richard created.

or you can buy a DC-Dc converter with current sdjust for about 20$ on ebay and connect the output in serie with your actual power supply. And to connect theinput f the dc-dc to the output of your charger.

It work very well.

i'm using that jfor my zero motorcycle 58.8V battery. I have few RSP-1000-48 power supply in parallel that are adjusted to 53.8V and i connected a 5V 60A DC-Dc converter in serie with the output to boost the voltage to 58.8V than i can adjust the current output o fthe Dc-Dc and it also control the overall outpyt current sinc eit is in serie. This DC-Dc have a 48V input so it accept up to 75V input and i connected this input to the output of the power supply.

Doc

 

[pm_dawn]

Hi !

I'm trying to set up this charger to end charging at 5A.
Does anybody know how to do that.

Or is it not possible ?

I have tried to adjust both W401 and W402, none of them seem to get the charger to cut off at any current.
What am I doing wrong.

Best Regards
/Per

 

[NeilP]

I do not think you can.

From what I have seen at ' End of charge ' indication when the LED changes colour, the only thing that happens is that the LED changes colour and the fan cuts out.
Possibly changes to CV mode, but I can't confirm that at all, just a total guess.

You could try adjusting the LED change pot up to max to see if that will go up that high.

Since you want to stop charge at 5 amps, I can only asdume that you have found that the pack is reaching a voltage you are happy to stop charge at.
So the alternative, if that is your aim, to stop charge at that lower half charged state is to reduce the charger output voltage to that which you require.

 

[dnmun]

his question is ambiguous to say the least. it implies he wants to know how to stop the charger from pushing more than 5A.

the only way the charger current drops off is because the battery voltage climbs up to the maximum charger voltage setting. when the charging current drops under a set value then the charger fn turns off and the charger continues delivering the balancing current until the battery reaches the final voltage.

 

[NeilP]

his question is ambiguous to say the least. it implies he wants to know how to stop the charger from pushing more than 5A.

You could well be correct. I was imaginin g charger that pushes out, 15 amps, 20 amps or more and he wanted to stop charging when charger current reaches 5A

when the charging current drops under a set value then the charger fn turns off and the charger continues delivering the balancing current until the battery reaches the final voltage.

I believe that is set by the "LED change colour adjuster" but I do not think it goes that high.

Till the OP gets back to us, no way f knowing what he actually means.

But if he wants to stop the charger from pushing more than 5 amps..then that is easy..in theory, it should just be done by adjusting the current limit pots 3 and 4 (W401 and /or 402) but he says he has tried that and they do nothing.

 

[pm_dawn]

Thanks for your input.

Maybe I was unclear. (I did not think I was but anyways...)

I want the charger to do CCCV charging.

CC level at 20A (its a 72v nominal 24s Lifepo4 charger)
Up to 85,2 (3,55/cell) and then hold that to when current goes down to 5A
Then I want the charger to cut COMPLETELY.
No Balancing, no Nothing after that.

Its a 24S 100ah Sinopoly pack so 5A@85,2 can be considered fully charged.

The W401 and W402 seems to control the Max current under CC phase.

Does anybody know if the charger can shut off or will it reduce the CV current down to 0.1A and stay there floating ?

Regards
/Per

 

[NeilP]

NO, that is clear, you were clear enough on your first post, that is what I thought you said

And the answer is that it is not possible in its standard form.

You would have to monitor the current somehow and then get that to monitor system to switch a relay to disconnect the charger from the pack.

If it is possible to set the LED to change from red to green at a current as high as 5 amps, then I guess it maybe possible to amplify the green LED driver signal up enough to drive a physical relay. I wouldn't know how to do it, but I can't see that it could not be done....anything is possible.

i guess it would be something along the lines of when the green LED comes on, it drives a transistor / Mosfet switch to either handle the charge current directly, or get the MOSFET to take the current that drives the relay. If the relay was a Normally Open contact then, a power failure would cause the pack to be disconnected from the charger too.

You may be able to tap power to run the relay energiser coil from the EMC-2000 , but probably safer to drive ti from a separate PSU.

Only ideas..I am sure dnmun will have a better way of how to achieve what you ask

 

[dnmun]

the way it knows to shift to the CV profile is when the current induced Delta voltage across a resistor in the current path drops below the voltage set point on the other side of the op amp that controls the leds.

on the 600W chargers the CV cuts in when the current drops below 450mA. but the charger will continue to push current right up to the voltage setpoint set with the trimpot on the end.

this charger has a different circuit from the 600W charger, but the principal is the same and i do not have one in front of me to look for the location of the resistor that would create that delta voltage. the trimpot will be connected to it, in parallel i assume. not sure which trimpot though. if you know which trimpot adjusts the max current during charging, then it will be the other trimpot that sets the current when it switches off the led rom red to green.

but this charger does not shut off totally. if there is a BMS then it will continue to push current through the shunts even as it reaches final voltage, and the pack voltage will not rise any higher once the current has dropped below the level that the shunts can handle.

if you have no BMS then the pack will charge up to the final voltage set point. at some point the pack voltage will match the charger output voltage and no current will flow.

for such a large pack, 100Ah there should be BMS that allows you to keep the pack balanced by fully charging all the cells and draining the high ones as it fills the low ones. but the BMS also provides short circuit protection and the LVC function to protect the battery from being damaged if left on accidentally.

 

[NeilP]

Seem to be two different sets of pics here...I know mine is a EMC-2000..but internal seem different..

These units have two current control pots and also an LED change colour trim Pot


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 = ?

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:

 

[dnmun]

i have only seen inside the EMC-1000 and it doesn't look like that but it does have a similar daughterboard as in the last picture. 1 and 5 set the voltage. if you look under 2,3,4 and see an op amp then follow the inverting input on the op amp, usually it is a dual op amp so you gotta look, and then find the traces that connect to the main current path that connects to that op amp and find the resistor that the trimpot is connected in parallel with. the trimpot that sets the CV current. then you would put another resistor on top of it in parallel so that the Delta voltage across the new smaller equivalent resistance would allow the charger to go to CV at a higher current. but not a good solution imo. 5A is way to high to stop charging imo. i recommend a BMS and balancing current.

 

[pm_dawn]

Hi !

Thanks again for your efforts. !

Seems I might have to add some cut off feature then.

The pack is bottom balanced and has no per cell LVC/HVC.
I do not plan to add one either.

Regards
/Per

 

[dnmun]

well no amount of good advice can overcome that. so sorry. let us know what happens.

 

[pm_dawn]

Hi All !

I'm really sorry if I stepped on your feet dnmun.
I do really appreciate your effort in helping me. But I'm trying do build a Clean, simple build in a thirties TT-Ford that is going to be used in a living museum. I have a tight budget and I have decided to go for the Bottom balance and undercharge method. You might find that stupid. That is partly why I choose the EMC-2000, because of price.
I read up on this site and this particular thread, where DocBass has stated that the potentionmeters would control the end of charge current. So I thought superb. Sounded like good bang for the $......

But if I cannot up the ending current of the charger so that it shuts of I don't really know what to do.
I might use the EV-Display to turn charger off at certain Ah.

I have a little problem following your case around the transition to CV phase.
In your 600w charger, what is your max current ? I would think much more than 450ma.
How can you say that Charger goes into CV at 450ma.
I thought that CV phase started as soon as the end voltage is reached during MAX current, so the charger has to start throttle the current down from max. Or Am I totally off in beliving that ?

I checked that specsheet for SinoPoly and they actually state C/50 as end current @3,8v as fully charged which is a little bit lower end current than the usual C/20 for LiFePo4. So I don't think 4-5A as ending current would be so undercharged.

Maybe one could use a latch and a SSR on the red led so when the Gren led goes on the SSR turns off the DC out of the charger. Then set it up so that you need to powercycle the charger to get the latch to turn on the SSR again.

When I tried to adjust the W401 I could get the sharging Led to switch from red to Green If I turned it almost to one end of the Pot. But the current would continue to flow.

Or perhaps one could use the output relay that is already there, have a latch that breaks the relay if the current goes below 2A, probably dont want to break any higher currents at 85v with that relay.

Best Regards
/Per

 

[dnmun]

i can tell that the 600W EMC charger goes into CV at 450mA because i measure it.

not my toes, i just feel sorry for you that someone has stuck you with this idea of how to charge and balance a pack that is so wasteful of good batteries.

 

[pm_dawn]

What kind of voltage does that 600w charger give 1200v ?
Do you mean when the Charging led turn green ?
If Not, what is your definition of CV in that case ?


And yes of course I meant your toes
English is not my native tounge so I tend to screw up sometimes when it comes to sayings.

I might just top balance the pack and go with a set of MiniBms shunts and a head end board.
But that would add a couple of layers of complexity.
That is so not what I need.

Best Regards
/Per

 

[madin88]

Hi guys, i have the EMC-1000 (900W alloy shell) charger from BMS battery and im still happy with it. No problems for so far.
The charger is set to 90V, 8A which is perfect for my 22s LiMn battery (charge to 4,1V per cell).

I have bought an amp / voltmeter display on ebay and now i want to wire it up. This meter measures 0-10A and 0-100V, but it needs a separately power source about 4,5-30V for the display itself.

my question: where i should wire this display to? There is a 12V fan (plugged to the vertical board with the pots) and the relay also is rated for 12V, so there must be somewhere a 12V source.
I do not want to disassemble the charger complete because everything is full of glue and sticked together.

this is the meter: http://www.ebay.at/itm/151180827541?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

EDIT: problem solved

 

[gone_walkabouts]

I am having a bit of a bad run at the moment with my electronics. I must be defying a few unwritten laws I have no idea about because in the last few days ..I may have blown up a controller (should have seen the spark and finger burns) , definitely caused my Cycle Analyst screen to stop working and now I have fiddle with my EMC 2000 charger and it no longer charges.

I have the board as picture below, it was working charging for 20s pack to 82v charging at 18 amps. I was able to go in and adjust the POT marked 4 to reduce the current to 6amps. All worked well !

Now that gave me the confidence, a few charges later, to go in an adjust the voltage so I could charge my 15s Lipo pack. This in when it all started to go wrong from me
I did this by changing pots mark 2 and 5 . This seemed to adjust the voltage down (indicator board read 62V however when the battery was plugged it did not trigger a charge. The setting on the display was 3 volts higher than the plugged in battery voltage.

So I wound up the voltage using the pots make to 82 volts and my 20s pack are not charging when plugged in. They are sitting at 75V.The charger is making a soft tick tick sound.

So can some one given me a brief description on how to re - set these chargers up for charging a 20s pack. I am perplexed at why there is a POT for changing the display voltage and what this mean in conjunction with the other for two pots on the main board.

The other crazing thing is changing the pots 2 and 5 now does not change the display voltage where it did when I first started adjusting the dame thing ! This is a bit random and at this stage I am perplexed.

Any ideas guys?




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 .

 

[NeilP]

The display voltage pot, is just a calibration for the display, that is all that does.

If it is still putting out voltage then hopefully all is not lost..but as for what has happened, n idea.

Maybe the range you have tried to adjust is just too great...not sure about adjusting down by that amount.

good luck

 

[gone_walkabouts]

Managed to get the display changing when I adjusted the pots...but if the display pot can change the display to read what ever you want...what is the true voltage set too

so how do you know what voltage the charger will output.....sticking a volt meter on the end of the output is only giving 7Volts....however is does say on the BMSbattery website

Warning:

there is a relay on the output of the charger, which other chargers do not have.
if you see a the negative voltage, it is normal, because the negative voltage is virtual voltage.
after you connect the battery, the relay will be connected to the output.
in this case, the voltage will not be negative anymore.
the relay is used for protect you.
without this, it is not that safe when you touch the plug of chargers.

SO assume you should not see voltage until something is connect and the relay kicks in >

So I am trying to work out how to set these charger up.........

 

[dnmun]

the relay on the output is to protect the charger from reverse polarity when the battery is attached to the charger.

it is the battery voltage that pushes current through a small diode and then through the coil of the relay. if the polarity is reversed, no current will flow through the coil and the relay will not energize the contacts.

 

[Doctorbass]

The best is usually to note the original position of the pot BEFORE to play with them and also if you adjust some of them, PLEASE count the number of turn you make and note that !!

I agree it can be easy to get lost after playing with them too many times and just use your memory to remind wich of the 5 pots are readjusted or not and how many turn! :?

having the original schematic I could help but this is complicated to adjust without any reference of the original setting and there is no test pin or reference voltage measurement..

We pay less for a 2000w charger and unfortunately we have to accept the risk too ..

some start might be to short the transistor that activate the relay to have it always ON and have the output active 100% of time.. then you can measure the real voltage on the output and also have the display working with it.

Doc

 

[dnmun]

there is no transistor that turns on to supply the coil but it would be possible to rewire the input to that diode so it takes the voltage from the positive output of the charge before the relay and that would keep the relay tuned on all the time.

but an easier solution is just to unsolder the relay from the pcb and remove it and then put a jumper wire across the spots on the pcb where the positive lead connects over to the positive output of the charge connects so it would be hard wired on all the time. i have repaired a charger with a bad relay this way.

 

[gone_walkabouts]

Thanks Doctorbass and dnmun for your replies....

Well I opted for the option to short the relay to see if I could get the charger working this way,

Took the board out and before I got there, i switched it on and puff....took out my house circuit..the board is shorted an we could not find out where.

Well a bit of an adventure for my friend and I, he was sure it was not going to go puff...I am calling him smokey from not on......

So in the market for an easily adjustable (voltage and ideally amps) charger to bulk charge 10s to 24s lipo packs....I assume they do not exist but I am looking high and wide for one !

 

[kmoonen]

Hey guys, i am repairing a EMC-2000 that was plugged into 220V without changing the voltage switch, i am looking for the value of Capacitor 201 (C201), would anyone be able to take a look and tell me what it is?.

Ken