Questions on Elcon/TC chargers

Post by **coulomb** » Thu, 17 Jun 2010, 04:13

I happened across a genuine Australian 20 A plug, from a Woods battery charger in fact. It shows that the Elcon supplied plug is in fact not suitable for Australian 20 A outlets (which are extremely rare anyway):

The 8 mm blade width would probably work with an Australian socket expecting 9 mm blades, but the active to neutral spacing is 11.5 mm, compared to our 7 mm.

It makes me wonder now whether our 240 V 10 A outlets are in fact compatible with Chinese 220 V power outlets, as I had assumed. They're both listed as "type I" on the Wikipedia "Mains power around the world" page, but I'm not sure that this implies plug compatibility.

Fortunately, the charger itself has a completely standard IEC male connector, so it's just a matter of finding a beefy IEC cord, or replacing the 20 A plug on the cord with an Australian 10 A plug.

Post by **antiscab** » Thu, 17 Jun 2010, 04:26

australian 10A plugs do indeed fit into chinese 10A sockets (as do UK and US plugs).

chinese power outlets tend to be of the universal variety...smart guys they are

Matt

Post by **elconcharger** » Sun, 08 Aug 2010, 01:21

Please refer to below website to find the updated specification, connection instruction of ElCon Chargers..
http://endless-sphere.com/forums/viewto ... 8&start=15

Post by **elconcharger** » Thu, 02 Sep 2010, 00:40

Please refer to the update connection instruction of control methods for LiFePO4 Battery Charger.
http://tg1a189.mail.163.com/js3/read/re ... ode=inline

Post by **a4x4kiwi** » Thu, 02 Sep 2010, 00:52

Hi, this link does not work.
Do you have a web page to link to?
Thanks,
Mal.

Post by **rhills** » Thu, 02 Sep 2010, 01:06

I don't read Chinese, but I'm guessing you need a username and password to be able to log in. Maybe then you also need to be able to read Chinese to read what's on the page?

Post by **antiscab** » Thu, 02 Sep 2010, 01:47

the link leads to a webmail server....

I have an elcon charger using the LiFePO4 control method.

basically when two pins are shorted, the charger runs, when open the charger stops.
if the pin later gets shorted, the charger runs again.
this continues until the CV until a certain current condition has been met.

www.evpower.com.au resells this variant with the correct control lead aswell.

Matt

Post by **7circle** » Thu, 02 Sep 2010, 08:51

There is New Elcon Charger posts on Endless Sphere regarding connections.
ES - Nancy's Post for: "connection instruction of control interface"

And more Pdf's on next few posts from Nancy

nancy on E-S.... wrote: See attachment connection instruction of control interface for Lithium battery chargers.

Connection Instruction for Control Interface of ElCon Charger.doc.pdf

Chargers' Pricelist...
Models & installation drawing...
Pricelist- ElCon Chargers.pdf
Models for EV chargers.pdf.

Updated User manual for Lead-acid battery charger
Updated User manual for Lithium battery charger

EV Chargers 24V,48V,36V,72V,84V,96V,120V, 144V~420V etc.,
User Manual for Lead-acid Battery Charger.doc.pdf
LiFePO4 Battery Charger User Manual.pdf

Its surprises me that the larger units are not cheaper per Watt.
Dec. 31, 2010

The Enable pin Operation and use cases are explained in the
Connection Instruction for Control Interface of ElCon Charger.doc.pdf

Post by **elconcharger** » Wed, 06 Oct 2010, 22:02

ElCon Charger has changed the brand name to TCcharger.

All the systems for chargers have been updated.

Contact: Nancy Loo

Email: nancylooloo@yahoo.cn

Post by **elconcharger** » Fri, 29 Oct 2010, 21:14

SAA certification will be available within two weeks.

Post by **elconcharger** » Thu, 18 Nov 2010, 19:49

EV Power (www.ev-power.com.au) stocks a range of TC Chargers for resale
in Australia. Please contact them if you require just one or two units
and they will do their best to help you.

Post by **jonescg** » Tue, 07 Dec 2010, 23:39

Hi Nancy,

I am using an interim charger purchased through ev-power. It is the 120 V, 10 amp 1.5 kW version. My pack voltage is 105.6 nominal (32 cells).

When it states 120 V, does that mean it is used to charge a 120 V nominal battery pack? That is, 36 times 3.3 V? Because it's output voltage is clearly more like 130 V! If this is standard terminology, then am I right in needing to get a 105.6 V charger?

Thanks,
CHRIS

Post by **coulomb** » Wed, 08 Dec 2010, 01:26

jonescg wrote: If this is standard terminology, then am I right in needing to get a 105.6 V charger?

Assuming it's not the CAN bus version (where the voltage can be programmed up to a maximum value that is about 1.5x the nominal voltage, atually 161 V for a 120 V charger), then it probably comes programmed with a set of algorithms suitable for various pack sizes. Most of these will be for around 40 cell packs (taking the nominal lithium cell voltage as 3.0) or 36 or 37 cells (since 120/3.2 = 36.5). The nominal voltage for lithiums is sometimes taken as 3.3 V, so maybe there will be an algorithm for 36 cells. Alas, 32 cells is not likely to be among them.

You can probably do a search to find what algorithms come standard with a 120 V nominal charger. You can order them (perhaps only if ordered direct from the factory) with particular voltages, or you can get them reprogrammed (I don't know of anyone in Australia that can do this though).

But usually, the algorithm is simply CC then CV at (number of cells) * 3.65, so perhaps 131.4 V for a 36-cell pack. This would be an average of 131.4/32 = 4.11 V per cell, which would be at the very high end for your cells (assuming that they are Thunder Skys). (If the are CALBs, then they have a strict charging voltage limit of 3.60 VPC, and a 120 V charger would not be suitable at all.)

So if you can adjust your BMS to tolerate 4.11 VPC (e.g. bypassing at 4.0 VPC), then you could perhaps use a nominal 120 V charger. I'd be a bit uncomfortable with it, though.

Ideally, you'd want about 32 * 3.65 = 116.8 V for the CV phase, so you might need to drop about 131.4 - 116.8 = 14.6 V. That's a lot of voltage to drop across some diodes, especially at 10A (146 W of power). You'd need about 20 diodes (at 0.7 V drop each), so say 10 power bridges. But that might be a way of using your 120 V charger, since you've purchased it.

The figures above assuming a 36-cell pack may need adjusting for whatever algorithm is designed for the lowest number of cells.

There is also the possibility of voiding the warranty by changing the internals:

http://www.diyelectriccar.com/forums/sh ... 51100.html

Post by **jonescg** » Wed, 08 Dec 2010, 18:06

Hmm, thanks for the insight Coulomb. I know there are different algorithms available, but the whole thing is a sealed unit, so I'm not sure how you would change it. There is no serial port either. How do these chargers work anyway? Surely if the maximum output is X volts, then the pack, connected in parallel with the charger would reach X volts? At this point the current will have dropped and the whole thing would be consuming a small amount of energy just keeping things topped up?

Post by **coulomb** » Wed, 08 Dec 2010, 22:00

jonescg wrote: the whole thing is a sealed unit,

Everything can be opened!

so I'm not sure how you would change it.

I thought that the PDF had some clues. Some models might be harder than others, of course.

There is no serial port either.

Not officially. I strongly suspect that the CAN bus versions have a serial port available on two of the pins of the 7 (?) pin connector. Maybe the non-CAN versions do too. I suspect that the serial port is also how they overwrite the programs. But the protocol doesn't seem to be documented.

How do these chargers work anyway? Surely if the maximum output is X volts, then the pack, connected in parallel with the charger would reach X volts?

Eventually. Initially, the pack will be down by 10-20 volts, and trying to lift a discharged pack to maximum charge voltage immediately would take say 200 amps. So initially, the charger's output drops to below maximum, so as to draw only the maximum that the charger can supply (in your case, 10 A).

At this point the current will have dropped and the whole thing would be consuming a small amount of energy just keeping things topped up?

Right. After some hours, the battery will reach the CV voltage, at which point the current will be much lower, say 6 A. When the current reaches a certain low value (say 2-5 A for one minute), the charger will decide that the pack is full and terminate the charge, drawing almost nothing from the mains, and not charging the cells any further. That cutoff current varies with the capacity of the pack (for 200 Ah cells, the cutoff current should be about twice the value for 100 Ah cells, for example). This is one of the choices you make when you select the charging "algorithm": you choose a combination of a CV voltage, and a cutoff current.

I think it may be possible to overcharge lithiums by leaving them indefinitely on "float" charge, even if the voltage is still within specification.

Post by **mcudogs** » Thu, 09 Dec 2010, 00:41

Here's a link to a mod that lets you change the final voltage point of the Elcon chargers.
Mod Elcon Charger

Unfortunately it will void the warranty.

Post by **elconcharger** » Thu, 09 Dec 2010, 00:56

Engineer from TCcharger pointed out that if you want to change the voltages, you have to alter those two voltage detection resistances simultaneously.

Post by **antiscab** » Thu, 09 Dec 2010, 02:38

Thanks for the clarification Nancy

I'm going to have a crack at this with my Elcon 1500W.

I have already opened my charger so the warranty is a bit gone.

I need to adjust mine down from 165v to 154v.

so many projects, so little time

Matt

Post by **jonescg** » Thu, 09 Dec 2010, 17:49

Let me know how you go Matt. Not that I plan on hacking mine just yet, but something to keep in mind.

Post by **jonescg** » Tue, 16 Oct 2012, 19:40

Hi all,
Sorry to revive an old thread...

But I have three Elcon / TC chargers set to 117 V - perfect for 32 S LiFePO4. All are in great condition, and if you want a really fast charge, you just parallel them!

Before I go any further - they are all for sale $350 each, or $1000 for all three, free shipping to anywhere in Australia. PM for details.

However, I am also considering hacking one of them to make it put out half the voltage so it can be used to charge a 16s LiFePO4 pack. How do you reckon I should go about this? Who would have the know-how?

It will be much easier to sell them, I think.

Post by **bga** » Tue, 16 Oct 2012, 19:50

Halving the output voltage should be easy with the above procedure.

One issue will be that the current will be the same, so it will become a 750 watt charger.

cheers

Post by **jonescg** » Tue, 16 Oct 2012, 20:17

Thanks Bruce. Does this mean the resistor will need to be pretty beefy to take the current, or is this just a voltage divider for driving other hardware?

Post by **bga** » Tue, 16 Oct 2012, 20:55

Just a voltage divider - the power will be less because the voltage is lower, so the same size will be OK

Post by **Johny** » Tue, 16 Oct 2012, 21:01

WRONG - IGNORE
Chris - just in case you haven't realised yet - the modifications in the pdf file are for raising the charger voltage wheras you are wanting to lower it. To do that you either place resistors in parallel with R1 (75K in diagram) or lift R2 and place a trimmer/resistor in series with it.

Edit: Sorry - the last part of the document shows how to decrease it - I should read more carefully.

Post by **jonescg** » Tue, 16 Oct 2012, 21:04

Yeah I was onto that, cheers Johnny. The power hit is a bit disappointing, but if I can't sell them as perfectly functioning 32s LiFePO4 chargers, I might as well make use of them for a 50 V scooter or the like.