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

I bought it and received it a week ago.

i'll try to review it and make some modifications to it.

I communicated with Jack Xie to confirm the adjustment potentiometer inside

W503 is for voltage
W401 is for end of charge current cut off adjustment
W402 is also for current adjustment ( probably the fine or coarse)
W4011 is also for voltage adjustment ( probably the fine or coarse)
W501 is for LED lamp indicator ajustment.

I had succed to adjust it to 12V to 105V and keep it stable.

I asked them for adjusting it for 100.8V and 15A.

They confirmed me that they can take 3% more for the current and for the voltage.. but i doubt about these data and i'll confirm. because they said it'S +/-3%.. but i acheived from as low as 12V to 105V.. so 12V is far lower than -3%.

I successfully installed an external panel mount potentiometer 10 turn Bourns quallity potentiometer fo rthe voltage and i'll make the same for the current...

That will make it like a lab power supply... :lol:

Mod 1: I also removed the original output cable and the input AC cable and replaced with quality CSA and UL 14/3 rubber flexible cable and quality Hubblle AC plug. This remove some weight to the charger cause the cheap chineese 2.5mm wires are too heavy for nothing and are not certified. And for the DC output, I installed ultra flexible 10AWG turnigy silicone wire and a good look protective aerospace looking skin!

Mod 2: Also .. for those who wonder if it is possible to make it giving power output WITHOUT the need to connect a battery to the lead and having this &?&?(&*!!! voltage detection circuit bypassed.. I say... YES it work... it's just a relay that is activated by teh presence of a battery with the right voltage range...

Mod 3:I also installed a jumper to the transistor that control the two powerfull blowers. I dont trust chinese electronic stuff of that power used in intermitent non cooled conditions!

Mod 4: I beefed up the traces of the power section with 10AWG euivalent ground cable

Mod 5:I am also installing some voltage sense to the output connector at the end of the output cord. By this way, my charger will push current longer period in the CC state ad charge the battery faster. Voltage sensing avoid the voltage lost in the output cord.. so the charger se the real voltage of the battery while pushing high current to it... and dont have the 0.1 to 1V loss in the wire that make the charger thing the battery is0.1 to 1V higher tha it really is!

This is the most complicated part of the mod. Usually all my meanwell have S+ and S- connection for the voltage sensing.. but these cehap chineese charger dont have this option as well...

I connected two additional little and twisted wires between the output charging connector and the charger circuit near the voltage feedback measurement is done in the PWM circuit.

What voltage sense make?.. let say the chrger is not connected to any load and that i measure 100.0 V
Than i connect a load to the charger to draw let say 15A... usually with teh voltage loss in the cable the real voltage i will measure at the end of the cable and near the load will decrease a bit and be probaly 99.5V depending on the wire size i used.

But with the voltage sensing feature the voltage near the load will stay 100.0V .. that fact will make the battery to keep being charged for more time at full curent! :wink:

Mod 6: I installed some silicon to to secure the loose parts from vibrations like the capacitors, transformers, inductors etc.

MOd 7: I also installeld some MS222 threadlocker to the nut that keep in place the transformer cause they was loose!!

Mod 8: I added a 4.7K 5W resistor in parallel to the output capacitor to discharge them faster when i turn down the voltage adgistment.. That clamp down the voltage and that avoid waiting that the capacitor discharge too slowly and keep the display to indicate higher voltage than the new adjusted V setpoint... A kind of simple crowbar circuit

Mod 9: I also added a Doc proof Diode against stupid reverse connections.. This is a dual parallel diode connected in serie with teh positive output!.. As well, the voltage sensing feature i added just keep the voltage setpoit to not loose 0.5V due to the conductioing shottky diode :wink: If i add 3 dide in serie.. or 100ft long output cable, the voltage sensing feature will alays keep the right voltage at the end of the cable. ) I t compensate for any V loss)





Doc

suite...

At full power ( 15A 104V) I measured a PF ( Power factor) of 0.74 wich indicate that it probably dont have any PFC circuit inside... like the RSP serie meanwell have..... But meanwell have max of 48V .. not 105V :wink:

Doc

Very nice work...thanks for that

the 900w chargers are the same? I've been thinking about bulk charging my 24s2p setup but didnt want to spend a fortune on a charger.

Well spend nothing and just string some PC PSU's together.

The basic ones (200 or 350 wtt or so) can put out 10 amps minimum on 12 volt line, usually 12 to 15 amps.

they have 12, 3 and 5 volt outputs, so a combination of them will give you the voltage you need. I have just got a string working today to charge a 20s4p pack 83 volts at 13 amps
Here is a thread I started about it...not updated to include it working as of today

http://endless-sphere.com/forums/viewtopic.php?f=14&t=28632

The solution of the EMC and almost the Meanwell is to have COMPACT PORTABLE chrger solution.

The best over all is the Meanwell RSP1000, RSP1500 or 2000 in the 1U shape .. you can cary it with you and it have similar size as a 500W meanwell and weight around 7pounds !¸

The RSP-2000 have 21.4W per cubic inch!!!... but it will require 120V 20A outlet...

the RSP-1000 is still the best portable powerfull solution and it can deliver 1250W continuous CC-CV

It cost 323$.. BRAND NEW not bad for that power and size! and it have a Power Factor Correction

http://www.trcelectronics.com/Meanwell/rsp-1000-48.shtml

This is why they are so great!

I would love one, but we are not all loaded with money to afford new stuff all the time,

I have one charger that is 2 Meanwells, that I use at home.
My crappy PC string is a 84 volt bulk charger that charges at 12 to 13 amp but cost nothing. As son as I can get enough I will re make using the 5 volt lines, and hopefully it will give 25 to 30 amps. Not compact by any means...but free and it can sit in the corner of the workshop in a packing case....240volt in 84 volt out..If I get fussy a volt meter and ammeter to monitor the output.

I was very tempted to buy one of these 2000W chargers earlier today after seeing the threads about them, but stopped myself. have spent over $2500 on building the bike...and the spending just has to stop. I do not need another charger, my 8 -9 amp home charge or (as of today ) 12 amp charge at the workshop will do me. If I build a bike for a friend, then I may get some free cash to buy one of these big Meanwells, but for now I guess I'll have to wait

Neil, mate. Be proud of your Ghetto charger. It does what you need, and is puts out a Kilowatt of Power. How big is your Batt?! :lol:

Even if you dropped 350+ USD on a fancy Meanwell, you'd still have to find some way to charge @ 84 volts!

Still, there are other cheaper PC server power supplies IE: from Server Supply in New York. Here's a thread:
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=27066&hilit=M7270

$30 USD for a 3000W 48V PS running on 220 V mains. NOT portable, but sounds like you want to leave it at the shop. Still need to solve the 84 V charge issue... maybe 2 in series if the Voltage can be trimmed down?

$50 for a 700W 48v PS that'll run on 110V mains. May be good as a portable charger for N.A. ebikers.

It's still sad, since we can buy PC PSUs on the 500W range for very little...

Hey Hey.. Hey. guys! . "Sad... cheap.. no need portable"... c mon guys.. I started this thread about good POWERFULL and PORTABLE AND SIMPLE solution!..

They ALREADY GIVE YOU THE VOLTAGE YOU NEED.. and ARE ADJUSTABLE for any battery mod you'll do...

I am so satisfied with these TOUGH and lightweight compact charger solution than i think it worth sharing that idea with the E-S

I am also part of a team that spread cheap charging solution.. I agree that PC power supply are good solution... but you will never bring them with you for a ride.. unless you have a cargo ebike :lol:

Njay... Yeah.. 500W.. but it work and will come out cheap solution IF your ebike is operating at 12V, 5V or 3.3V.... :lol: :wink:

Doc

I agree that the supplies that Doc mentions are great and a lot of power in a small space.

I do already have a compact 700 W Meanwell charge setup, built in small Powertool box, still would get one of these 2000W units if I could . Actually I was all set to order one a day or so ago, but stopped myself....I do not need another, It was just the POWER calling

I only mentioned the PC PSU solution here as zombiess mentioned not wanting to spend much. It is possible to build a PC PSU string for nothing, all my psu's came from the dump, so free apart from cost of solder, heat shrink and time

Holocene said:

Neil, mate. Be proud of your Ghetto charger. It does what you need, and is puts out a Kilowatt of Power. How big is your Batt?! :lol:

Click to expand...

My pack is nothing special,20s4p 20ah, so am trying to achieve a greater than 1C charge rate

Doc,
Do you know if the lower power EMC or DEMC models from ecitypower are adjustable also? I have a EP3012AL that I purchased from them a few years back. It's rated at 29.2V @ 12A. I adjusted the pots and am now charging to 27.6 (8S, 40Ahr Calb pack) @ 16A. I did not make any other modifications other than using an external fan to help keep it cool. So far, so good.

With these chargers on the market....
and them being so powerful, cheap, and adjustable...
why are we using meanwells?
they're only SLIGHTLY cheaper, require modding, and aren't nearly as adjustable.

I would say we are using Meanwells because they have been available longer for cheaper, As the EV. Market increases, I am sure more products like this are going to appear, more powerful and cheaper.... and better

It is only a matter of time before all the mods Luke has done to his charger become built in as standard, especially if a supplier gets requests from the likes of us to incorporate them



Doc, could you put a close up pic of how you wired the Voltage sense wire at the charger end ...near one of the pins of the control IC I guess? a TL494? or some op amp or comparator?

Doctorbass said:

I communicated with Jack Xie to confirm the adjustment potentiometer inside

W503 is for voltage
W401 is for current adjustment
W402 is also for current adjustment ( probably the fine or coarse)
W4011 is also for voltage adjustment ( probably the fine or coarse)
W501 is for LED lamp indicator ajustment.

I had succed to adjust it to 12V to 105V and keep it stable.

I successfully installed an external panel mount potentiometer 10 turn Bourns quallity potentiometer for the voltage and i'll make the same for the current...

Mod 1: ...cabeling
Mod 2: ...power supply into a battery... it's just a relay activated by the presence of a battery...
Mod 3: ...control the two blowers
Mod 4: ...beef up traces
Mod 5: ...voltage sensing to avoid line drops
Mod 6: ...anti vibes measures
Mod 7: ...anti vibes measures
Mod 8: ...add 4k7 / 5W resistor to discharge output capacitor
Mod 9: ...add diode against reverse connections ...As well, the voltage sensing feature

Click to expand...

thx for this info, Doc
I received my EMC-900 (100.8V) three days ago and was just about to start a similar work you have just done - loads of time safed!!!
Could you map the trimpots you mentioned to the location in the following picture?

it's obvious that the layout of the EMC-900 (EMC-1000 on the PCB!) and the EMC-2000 are much different. The EMC-1000 uses a separate PCB for the logic circuitry and places the trimpots at the top (very handy). The labels/numbering on the PCB seem to be the same though and read (comments copied from Doc):

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

My words were just words of frustration because these chargers and PSUs and PC PSUs are basically the same technology... but at a very different price.

rolf_w said:

Doctorbass said:

I communicated with Jack Xie to confirm the adjustment potentiometer inside

W503 is for voltage
W401 is for current adjustment
W402 is also for current adjustment ( probably the fine or coarse)
W4011 is also for voltage adjustment ( probably the fine or coarse)
W501 is for LED lamp indicator ajustment.

I had succed to adjust it to 12V to 105V and keep it stable.

I successfully installed an external panel mount potentiometer 10 turn Bourns quallity potentiometer for the voltage and i'll make the same for the current...

Mod 1: ...cabeling
Mod 2: ...power supply into a battery... it's just a relay activated by the presence of a battery...
Mod 3: ...control the two blowers
Mod 4: ...beef up traces
Mod 5: ...voltage sensing to avoid line drops
Mod 6: ...anti vibes measures
Mod 7: ...anti vibes measures
Mod 8: ...add 4k7 / 5W resistor to discharge output capacitor
Mod 9: ...add diode against reverse connections ...As well, the voltage sensing feature

Click to expand...

thx for this info, Doc
I received my EMC-900 (100.8V) three days ago and was just about to start a similar work you have just done - loads of time safed!!!
Could you map the trimpots you mentioned to the location in the following picture?

it's obvious that the layout of the EMC-900 (EMC-1000 on the PCB!) and the EMC-2000 are much different. The EMC-1000 uses a separate PCB for the logic circuitry and places the trimpots at the top (very handy). The labels/numbering on the PCB seem to be the same though and read (comments copied from Doc):

1 = W503 ; is for voltage
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 ; is also for voltage adjustment ( probably the fine or coarse)
6 = ?
7 = ?

rolf

Click to expand...

Since this is a different board, i thing that the pot label are not the same.. so best is to communicate with Xie on bmsbattery online contact during the night... ask them what all pot are doing like i did. I dont want you to blow som,ething by using the same info for your EMC 1000

Doc

Doctorbass said:

1 = W503 ; is for voltage
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 ; is also for voltage adjustment ( probably the fine or coarse)
6 = ?
7 = ?

Since this is a different board, i thing that the pot label are not the same.. so best is to communicate with Xie on bmsbattery online contact during the night... Doc

Click to expand...

the above mapping of trimpot labels and location on the EMC-1000 PCB is according to the actual letters on the PCB. Their assumed function I simply copied from your list, hoping they are the same - I will ask Xie to confirm (do you have his email? or simply is the website contact?)

rolf_w said:

Doctorbass said:

1 = W503 ; is for voltage
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 ; is also for voltage adjustment ( probably the fine or coarse)
6 = ?
7 = ?

Since this is a different board, i thing that the pot label are not the same.. so best is to communicate with Xie on bmsbattery online contact during the night... Doc

Click to expand...

the above mapping of trimpot labels and location on the EMC-1000 PCB is according to the actual letters on the PCB. Their assumed function I simply copied from your list, hoping they are the same - I will ask Xie to confirm (do you have his email? or simply is the website contact?)

Click to expand...

During the night, they are online for skype :wink:

Well, at my 900 watt charger is the w503 also for voltage, im pretty sure the rest is also the same.
But how to measure the voltage exactly ? When no battery is connected it won't give any voltage, any tricks to do this ?

Bazaki said:

Well, at my 900 watt charger is the w503 also for voltage, im pretty sure the rest is also the same.
But how to measure the voltage exactly ? When no battery is connected it won't give any voltage, any tricks to do this ?

Click to expand...

Easy :wink:

You will find a big tBLACK relay of 30A or more connected in serie to the output positive lead.. Just connect a 1K or so resistor across the two contact of this relay ( not across the coil contact!). and you should get output voltage you expect at the cahrger output.b

These EMC charger are made so that it need to detect a battery voltage present at the output to activate the output by closing the relay contact.

You need to know that the charger output power is always availlable but it's on the first contact of the relay... and you need to put voltage that is detected by the circuit to make the relay to activate and close the contacts to have the current flow to the output of the charger.

When you connect a resistor across the two contact of that relay, you simply fake that a voltage is present at the output befcause the voltage that travel the resistor will make a bridge from the always active output to the positive output connectionof the charger... so the circuit "think" a battery is present and it activa the relay, giving you power availlable at charger output :wink: You just need to momentanously connect that resistor.. and it will toggle the output.

You can also install a push botton that will connect the resistor to the relay in a premanent installation.. to let you be able to activate the output without a battery detection activation...

Thanks ADoc, sounds good to me.
In the mean time I did play arround some more and I found another trick, I switch on my bike, hook up the charger and let it charger, then I switch off my bike, and the charger is still in parallel with my controller, so the charger will continue with " charging" although this might be a bitt less accurate since there is some resistance from the charger, anyway it was enough to set the charger to 75,00v

What kind of range you think will this charger have with only trimming the W503 pot ?
I have ordered a few set at 100v and a few at 75v, I'm not sure if there is any difference in hardware between them ?

A sidenote, I ordered 9 of these, 2 are totally dead, maybe fixable ? Doc. maybe you got a tip for things I could simply check ? almost all the others have a broken FAN, that means that the FAN can't blow anymore and if I didn't repair it, the charge would probably overheat.

Bazaki said:

Thanks ADoc, sounds good to me.
In the mean time I did play arround some more and I found another trick, I switch on my bike, hook up the charger and let it charger, then I switch off my bike, and the charger is still in parallel with my controller, so the charger will continue with " charging" although this might be a bitt less accurate since there is some resistance from the charger, anyway it was enough to set the charger to 75,00v


I have ordered a few set at 100v and a few at 75v, I'm not sure if there is any difference in hardware between them ?

A sidenote, I ordered 9 of these, 2 are totally dead, maybe fixable ? Doc. maybe you got a tip for things I could simply check ? almost all the others have a broken FAN, that means that the FAN can't blow anymore and if I didn't repair it, the charge would probably overheat.

Click to expand...

What kind of range you think will this charger have with only trimming the W503 pot ?

Click to expand...

You need to try and turn it on both side until the charger make a tic tic sound.. wich mean you reached the max pwm or a bit above the power handling of the components that are the limit.

I dont know the 900W and 1000W.. but the desing is pretty similar.

Probably that that broken one can be fixed.

you MUST repair the one with the broken fan! :wink:

Thanks, I did a check and I can adjust the voltage at least from 50 - 100v, lower and higher I didn't try, I was afraid to blow something up.

The FANS that were broken are fixed, but 2 of them won't do anything, no idea's of what might have been broken ?