Page 2 of 4

Questions on Elcon/TC chargers

Posted: Fri, 14 May 2010, 05:30
by coulomb
I'm still mystified by what the CAN bus connector is going to be. From this image (315kB) from this great blog site, is this:

Image

My first guess is that the CAN connector will be the same 7-pin round connector that is documented. In fact, one document says "Connect CAN bus through plugging in CAN module (Model TC-619B), then use 2, 3, 6,
7-pin." The white collar on both connectors lends support to this idea.

However, that disagrees with this circuit:

Image

From http://lithiumate.elithion.com/php/elco ... th_CAN_bus

I'm assuming that "CAN module" is the little box that plugs into ElCon chargers when you buy the CAN bus option. 1 and 3 are different pins to what I would expect for the two CAN signals (I'd expect 6 and 7), and they had to tap into the original cable, so it seems that if it's a 7-pin round, it doesn't have all the other wires extended.

Others have suggested that it looks like a BNC connector, but using the IEC power connector as a comparison, it's too large. Besides, you need at least 3 wires for CAN (CAN-hi, CAN-lo, and CAN-gnd), which isn't possible with BNC.

Elconcharger, perhaps you have more information on that CAN connector?

Edit: I forgot to mention that Weber has ordered a 312 V nominal (417 V max) 5.5 A (2000+ W) charger with CAN option for the MX-5. So I guess we'll know in a few weeks.

Questions on Elcon/TC chargers

Posted: Fri, 14 May 2010, 21:35
by bga
Hi Coulomb,

I'd be very interested in how you ordered it. I have been considering two of the 288V version.

The idea being to simultaneously charge the battery as two 256V halves. I don't know how the isolation and grounding is arranged on these chagers, so they may not be compatible with this approach since the DC outputs will be at 300V with respect to the case.

I did receive some information from nancy:
It looks like the 'enable' line is linear, so variable charge current can be obtained by applying differing voltages or resistances. This sounds great for power supply limiting (10 amp outlets) and final equalisation charging.

I think that, with some external smarts, the CAN bus may be avoidable.

Cheers

Questions on Elcon/TC chargers

Posted: Sat, 15 May 2010, 00:09
by coulomb
bga wrote: Hi Coulomb,

I'd be very interested in how you ordered it. I have been considering two of the 288V version.
Weber emailed Nancy directly. As with most Chinese suppliers, they want Telegraphic Transfer for payment. There seems to be a glitch on the amount transferred; hopefully it will be sorted soon. The charger seems to be manufactured and ready to send. I guess we could see it next week.
The idea being to simultaneously charge the battery as two 256V halves. I don't know how the isolation and grounding is arranged on these chargers, so they may not be compatible with this approach since the DC outputs will be at 300V with respect to the case.
We considered this, but will likely retain the ability to split the pack into two halves for charging. It seems less dangerous to charge at half voltage.
I did receive some information from Nancy:
It looks like the 'enable' line is linear, so variable charge current can be obtained by applying differing voltages or resistances. This sounds great for power supply limiting (10 amp outlets) and final equalisation charging.
Yes, this is indeed interesting news! If our charger is usable without the CAN bus, we might investigate this. One of the Drivers Controls' gauge outputs, possibly slightly modified, could drive it, and keep the mains current to a selected level, cut back charge current when a cell overvoltages, and ensure that the final charge current while some cells are bypassing doesn't exceed the capability of the bypass resistors. It sounds like a lot less work that getting the CAN interface going, especially if it can't be on the same CAN bus as the controller.
I think that, with some external smarts, the CAN bus may be avoidable.

Agreed!   Image Thanks for the info.

Edit: minor changes for clarity re TT.

Questions on Elcon/TC chargers

Posted: Sat, 15 May 2010, 14:43
by coulomb
mcudogs wrote: Here's a link to the CAN protocol.

Ah, Don, I see from your blog that you have one of these chargers. Did it come with a 7-pin plug, or did you have to chase around and figure out where to buy one?

Did you get the CAN option? If so, you could tell us what the connector is.

How does your open-source BMS control the charger?

Questions on Elcon/TC chargers

Posted: Sat, 15 May 2010, 18:45
by coulomb
Ok, I have some information, thanks, Nancy!

It's a two-wire connector:

Image

The part number of the connector is not given, but presumably it's in the same series as the 7-pin for which the part number and manufacturer are given somewhere (I think on an Elithium page), and in any case, hopefully a suitable plug comes with the charger.

There is more information on the linear control mode; unfortunately, I can't seem to upload that manual at the moment. The relevant part is here:
2. Battery protector option. This is a working mode when use battery protector or BMS which has no CAN communication function. Charging can be switched on or off the charging through charging enable control wire:
(1) Charging process: When two enabling wires connect, charger starts cc charging while gets the external signal. And begin to charging CV when it reaches max voltage. During CV period, it stops charging automatically until current falls until to a preset value. If external signal is removed, charging stops as well.
(2) PINs description:
PIN 1: the input of enable voltage test.
PIN 1 can control the working status of charger and can set maximum output current.
PIN 2: GND
There is 10K ohm resistor in the inner of PIN 1 and PIN 2
PIN 3: 12V power output
(3) Control mode: During the stop state, charger will enter into working status when more than 2V between PIN 1 and PIN 2.
During the working state, charger will enter into stop state when less than 1.5V between PIN 1 and 2. Voltage of 2V~5V
between PIN 1 and PIN 2 corresponds output current 0%~100%. For example,
When it is 2V between PIN 1 and PIN 2, the maximum current of charger output is 0;
When it is 3V between PIN 1 and PIN 2, the maximum current of charger output is 33%;
When it is 4V between PIN 1 and PIN 2, the maximum current of charger output is 66%;
When it is more than 5V between PIN 1 and PIN 2, the maximum current of charger output is 100%;
(4) Method of Use:
A. If you only need charging enable function, please connect PIN 1 and 3 (you can use relay or opticalcoupler), then charger
starts working; Disconnect the PINs, charging stops. Re”connecting PIN 1 and 3, it will re”start to charge.
Wiring mode: Use the contact of external relay and connect PIN 1 and 3. Or you can use opticalcoupler to control the enable wire. Current direction is from PIN 3 to PIN 1. The current”output capability of opticalcoupler should be up to more than 1mA.
B. If you need to control the charging current based on the enable control, you can control the voltage between PIN 1 and
2 to realize it.
Wiring mode: First use PWM to drive opticalcoupler and then use a RC filter, then it will be 0~5V. You can also use other modes which can obtain controllable DC electrical level.
From my reading of this:
1) Control may only be possible in "stop mode" at the end of charge.
2) All the above may not work at all if the charger is configured in CAN mode.

Questions on Elcon/TC chargers

Posted: Sat, 15 May 2010, 19:02
by coulomb
Thinking about the analogue control a bit more, it would seem that connecting pins 1 and 3 is just a crude way of putting "at least 5V" on the control pin, pin 1 (pin 3 is at about 11 V wrt pin 2, which is like a controller ground). So if you put say 4V on pin 1 (wrt pin 2), it would seem that you might get 66% of maximum current during the CC stage, e.g. in case you had an outlet that you didn't dare draw too much current from while charging on the road. You could connect a pot and pair of zeners to allow complete control over charger current, if I'm right.

Sadly, all this is probably disabled when the CAN option is enabled, and it may not be a simple process to "switch off" CAN mode. Still, CAN mode will give control over the maximum voltage as well as maximum current, and should provide a little information as well from the broadcast packets.

Ooh, it's just occurred to me that if two chargers are used (e.g. to charge the two halves of the pack separately), it may be necessary to get one to have a different CAN id to the other. That way, when you get status information, you'll be able to tell which one it came from. However, voltage and current limits would presumably go to both chargers; there would be no way to say "charger number 1, give me 4 A, and charger number 2, give me 0.9 A".

It's starting to look as though it will be useful to drive the chargers with RS232, assuming we can figure out the protocol. Then we can drive and read the chargers independently. I suppose we could also use two separate CAN buses, but that starts getting expensive and awkward.

Questions on Elcon/TC chargers

Posted: Sat, 15 May 2010, 19:50
by 7circle
coulomb wrote:
...
From my reading of this:
1) Control may only be possible in "stop mode" at the end of charge.
2) All the above may not work at all if the charger is configured in CAN mode.


Wow great info.

The "STOP MODE" appears to be a the range 0V to 2V on the Enable pin.

0V < Venable < 2V : STOP MODE
2V < Venable < 5V : Scale output Constant Current limit 0% - 100%
5V < Venable < 12V : Scale output 100% of Constant Current limit

The dead band on the bottom is usefull for ignoring noise (EMI) on connecting control long wires in high current areas.

What would be good to know is, does the Scaling effect the charge current condition (ie 0.05C) that defines end of charge.

Looks like the ELCON will be very versatile.
Image

Questions on Elcon/TC chargers

Posted: Sun, 16 May 2010, 00:36
by mcudogs
coulomb wrote:
mcudogs wrote: Here's a link to the CAN protocol.

Ah, Don, I see from your blog that you have one of these chargers. Did it come with a 7-pin plug, or did you have to chase around and figure out where to buy one?

Did you get the CAN option? If so, you could tell us what the connector is.

How does your open-source BMS control the charger?


Yes it came with a plug with a 2 wire cable connected to the enable pins.

No sorry I didn't get the CAN option.

The BMS just enables the charger via an opto. If any of the cells exceed the max volts it disables the charger.

I wasn't told anything about the analogue control, maybe it wasn't included in my version. It sounds like a good way of cutting the charge current if you keep tripping breakers on the 240 input.

Questions on Elcon/TC chargers

Posted: Tue, 18 May 2010, 19:57
by bga
Hi Don,

You should be able to program the charge current with a resistor.
Only some of the documents seem discuss this and I only discovered it after Nancy sent me a document.

I was thinking the same, and also being able to reduce the charge current when bypass resistors are on so that the charged cells are effectively bypassed. Stopping at full charge should be easy as well.

Could I ask you to look at the isolation of the various charger I/O?
battery +/- to chassis earth and
battery +/- to control input / LEDs (or chassis earth)

I am considering two chargers is series with a connection to the middle of the 512V battery. If the B- output is grounded in the charger there's going to be a bang and I'll have to give up on this idea or bend the chargers.

I don't know that it would stop me buying them, but it would make a difference to the confguration.

Could you try a bit of multimeter probing?

Questions on Elcon/TC chargers

Posted: Wed, 19 May 2010, 01:59
by mcudogs
The battery output terminals are completely isolated from the AC input and ground. The control terminals are not isolated from the battery -ve, so you will have to isolate your control circuits. I just drive mine with an opto.

Questions on Elcon/TC chargers

Posted: Sat, 22 May 2010, 20:18
by bga
Thanks don,

That would make sense if the charger looks like every other switching power supply. Isolating the control interface isn't a big deal and is good for reducing disaster potential.

I must get my ordering underway. Pity that the dollar took a hit this weekImage

I'm still not convinced that 2 x charger is a good idea, but it will make for a faster recharge, provided that there is a 20 amp outlet handy. The concern is that two may not fit in the vehicle so well. A spare is a good thing in any case.

Questions on Elcon/TC chargers

Posted: Sat, 22 May 2010, 20:30
by weber
With two chargers you don't need a 20 A outlet (rare as hen's teeth). If you take two extension leads you can use two 10 A outlets that are on different circuit breakers (reasonably common).

Questions on Elcon/TC chargers

Posted: Sun, 23 May 2010, 23:35
by antiscab
or you could use a 3-phase point, and only use 2 of the phases.

lots of options :D

Questions on Elcon/TC chargers

Posted: Mon, 24 May 2010, 14:11
by coulomb
antiscab wrote: or you could use a 3-phase point, and only use 2 of the phases.
Oh, right, a 5-pin socket (most of them are, I think), using two phases, neutral, and earth. Good idea; that certainly guarantees two different circuits, and the ability to draw significant current from each. Another adapter to carry around.

Edit: emphasise neutral.
Edit2: "two different phases" -> "two different circuits"
Edit3: I guess if the adapter had three single phase sockets, you could manually juggle the phases to achieve the best phase balance.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 00:56
by coulomb
Now that our own charger has arrived, I can answer a few of my own questions about what the CAN connectors look like:

Image     Image

The 7-pin connector:
Image

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 07:28
by 7circle
Good Pics Coulomb
Wondering if the charger can be configured to only charge 4 cells.
That's way below your desired config. But was wondering if the parameters can be set over the serial port or CAN bus.

When you get a little box that can can covert serial to CAN bus I wonder what else the uController can do thats in there.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 07:49
by 7circle
From Weber and Coulomb's MX-5 Weber % Coulomb's MX5
coulomb wrote: The charger also arrived recently:
Image

... a standard IEC cord, so we can just use a beefy computer cord instead.


Was wondering about the nameplate.
see picture above wrote: OUTPUT: TCCH-416V-5.5A
          416V--3A@100V AC
3A@100V AC Is this indicating ripple?
This makes me wonder how much ripple there is during charging.
Less of a problem for LiFePO4 than for LEAD ACID.

And does the charger mains lead come out direct or via IEC socket.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 08:06
by evric
I think what it's trying to say is that the output current is normally 5.5A but if the AC input drops to 100V AC (or 200V AC in Australia) then the available output current is only 3A.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 17:45
by coulomb
evric wrote: I think what it's trying to say is that the output current is normally 5.5A but if the AC input drops to 100V AC (or 200V AC in Australia) then the available output current is only 3A.

Yes, it's just over half output with 100 VAC input. With 200 VAC, it would be derated very slightly; there isn't a switch for 120/240 V operation.

I think it's just a current limitation on the input circuitry. Probably the "PFC" stage.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 17:48
by coulomb
7circle wrote: Does the charger mains lead come out direct or via IEC socket.

It comes out to an IEC female connector. The 20 A IEC cord (if that's what it is) is separate. We did specify that this was for single phase 10 A operation.

Questions on Elcon/TC chargers

Posted: Thu, 27 May 2010, 17:55
by 7circle
evric wrote: I think what it's trying to say is that the output current is normally 5.5A but if the AC input drops to 100V AC (or 200V AC in Australia) then the available output current is only 3A.


Yep, Thanks Evric, It's the derated output not ripple Image.

As they group the input in two ranges 100-130 and 200-250.
perhaps they parallel they don't parallel the primary of the isolation transformer. So I wonder if they provide a better derating curve in the manual.
When I was a teen I wished Australia only had 55V to ground instead of 240V Image.
But when your paying for stuff, better power throughput is good.

Main thing is the charger keeps the batteries healthy.

Questions on Elcon/TC chargers

Posted: Mon, 31 May 2010, 02:25
by bga
Hi all,
I paid for a pair of chargers on friday, but it looks like USD25.00 disappears on its way to China.
I think that the same happened to Weber/Coulomb.

Elcon is devloping a programmer that should be available shortly and will hopefully take the guess work out of ordering these things.

BGA

Questions on Elcon/TC chargers

Posted: Mon, 31 May 2010, 15:47
by Johny
That happened to me on my AC motor purchase to Taiwan and battery packs from China. It varies a little from bank to bank but is generally AU$20.
On the battery purchase I couldn't pay all at once due to limit on daily withdrawal so I incurred it three times.

Questions on Elcon/TC chargers

Posted: Tue, 01 Jun 2010, 04:52
by EV2Go
Had that seperate charge turn up a couple of times on purchases in the US. It's a Aussie dollar conversion cost.

Questions on Elcon/TC chargers

Posted: Sun, 06 Jun 2010, 20:27
by bga
This must mean that the import bank to the US is charging a fee. I've not had a problem previously, but with smaller purchases these fees have become more significant.

Update of my funds transfer issue.

It's the US exchange bank that does it in transferring USD to China. Westpack uses Watchovia to do this.

I talked to my local branch and explained that I was objecting to not having been informed of the external fees and that while they are outside the control of the bank, they are not outside it's knowledge. They were very helpful and there's a very good chance that they will resolve this amicably.

I'm trying to get the bank to change the way they process overseas TTs so that customers are made aware of external fees and can accomodate these so that nobody's surprised by the outcome.