1100d external power help

[JAS]

I have removed the internal battery from a cheap copy canon battery and conected the live and nutral to the correct terminals. This is then attached to a 8v psu.

There is 7.9v at the battery terminals, but when I put it in the camera it says to replace the battery and shows a red battery symbol.

It looks like the camera uses 3 of the 4 terminals of the battery, do I need to have anything conected to the third terminal to make this work?

Thanks Jason.

[Gina]

I took a battery apart and found the contacts were just on the little PCB and I couldn't see where to connect the power so I thought rather than get it wrong and damage the camera I'd buy a proper adapter. Then I bought a cable to connect it or so I thought but the plug was the wrong size. I think I'm going to butcher the adapter and connect my own cable. The adapter has three contacts like the camera so evidently the third contact is used. I guess it's used to determine the state of the battery. The batteries have chips inside which I guess send data to the camera through this third contact.

When I take the adapter apart I'll take a photo of the insides and post it. I may well be able to see how the third contact is connected.

[JohnC64]

Hi Jason,

If you don't succeed with the mod to the battery case, I bought one of these from ebay AC Adapter For Canon ACK-E10 ACKE10 EOS 1100D Rebel T3 | eBay

At £9.59 its a bit of a bargin

Cheers John

[yesyes]

I seem to remember that I used a 10k resistor between GND on the battery and the 3rd terminal labelled T. This "fooled" the camera into thinking the "battery" is 80% charged. That was on a 1000D though and I'm not so sure about the 10k resistor value now. If you still have a working battery and a multi-meter, charge the battery fully and then measure the resistance between GND and T.

[Gina]

The third contact goes direct to -ve in the Canon adapter. It has + and - labels on the case for the outer two contacts. Here's a photo of the circuit board. This is a genuine Canon beasty which cost me £25 from Amazon. Took a lot of getting into

[Islander]

Are those ferrite beads or dummy links made for automatic insertion?

[yesyes]

Gina, can we have a picture of the other side of the board, please?

[Gina]

They look like ferrite beads to me but they aren't loose on the wire - a definite component. Can't detect any resistance on my digital multimeter which means it's less than 0.1 ohm.

[Gina]

Gina, can we have a picture of the other side of the board, please?

OK, will do

[Gina]

Other side of PCB and the case showing polarity labels.

[yesyes]

this looks odd.... why do they have to re-invent the battery with each camera model?

So does this battery only have 2 terminals or is the GND metal piece serving 2 terminals (it looks a bit bigger than the other terminal)

[Islander]

Some Canon cameras use batteries are chipped and that feed data back to the camera. I suspect that this is what the extra terminal is actually for.

[yesyes]

with the 1000D battery this seems to be some analogue signal, rather than a chip sending digital data.

Some said that the T terminal is only for measuring temperature during charging to avoid overheating. But that can't be right as it seems to have an influence on the level of charge displayed on the camera.

[Islander]

I've been having a dig around to see if anyone's reverse engineered the so called smart batteries but can't find anything. I think it only applies to the pro and semi pro models anyway.

[JAS]

Thanks for all the input.

I have a fully charged canon battery at home, I will put the meter on it tonight. I will also post pics of the insides of the doner battery.

Jason.

Sent from my LT15i using Tapatalk

[Gina]

Yes, the -ve contact is extra wide and connects to two of the contacts in the camera.

"Smart" batteries contain a "1-wire" chip that measures the accumulated input charge and output charge plus the temperature. The data is fed through one contact (hence the name "1-wire") with data flowing both ways. The host system interrogates the chip in the battery to collect the info. Incidentally, each 1-wire chip has a unique serial number lasered into it so you can have any number on a 1-wire bus in the same way as USB but with many more ID codes.

But why Canon should feel the need to keep changing the battery type I have no idea. I can see that they might have two types - one very simple with perhaps an analogue charge state indicator and another giving more info but anything more than that beats me.

[Islander]

Some Canon batteries are 4 contact, some are 3 contact. Contact positions vary too as do battery profiles and hence, chargers. It's all about selling accessories. Some of the original 1 series chargers are horrendously expensive - internally they won't be much different to the basic consumer models.

Great cameras and lenses though

[JAS]

This is what was inside.

The top of the battery, showing the terminal from each cell.

The bottom of the battery, the cells are joined here and the extra terminal goes to the pcb.

The terminal BC was connected to the bottom of the battery.

B+ and B- were conected to the top of each cell.

The 4 terminals that connect to the camera/ charger.

I put a meter on the cells, they show 7.75v across the top terminals and 3.87 from eather of the top terminals to the one that comes up from the bottom.

I have attached my input where the battery input was (B+/B-), and have had the same result. I am thinking I need to add 4v to the BC terminal to get this working?

What to you think?

What woud be the easy way to do this?

Jason.

[Gina]

I have mine working. That's using the 3 contacts that are used by the camera with the middle one connected to the GND or -ve contact. With this connection method the camera shows being on mains power rather than battery. This is shown in the various programs eg. EOS Utilities and APT. EOS Utils shows a mains plug instead of a battery symbol and APT reports AC rather than a percentage charge remaining.

I've been running the 1100D on mains power all evening.

[JAS]

Thanks Gina, I will conect the middle to v- and give it a go.

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[Gina]

You're welcome

BTW - I checked the current as well as I'm currently running it off my variable bench PSU and it was running at 0.33A.

[JAS]

I have just wired it up as Gina said and it is working:-)

I had it set on rapid shoot, and took about 60 continental shots and all was good. The camera does not say it is mains fed as Ginas does, I will see what backyard eos says later.

I am using a 2 amp regulator with a heatsink in my hub to power it so that should cover it.

Thanks for all the input, and thanks to Gina for cracking open her mains adapter to solve the problem.

Jason.

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[SniffTheGlove]

I know this thread a 18 months old but thought it would be better to post here than start a new thread.

Having brought a 1100d I soon ran out of battery juice, so I ordered a cheap battery off the ebay for £4 (surprised it only took a week to arrive from China), carefully sliced it apart and took the inards out. I then made up a new contact pad using thin copper sheets superglued to some thin plywood and soldered on 3 wires (+ T -), using the above posts I connected the T and the - together so now have onely two wires coming out of the case (+ -). I run this to wire to a 12vdc/7.5vdc converter I have from Caravan Technology http://www.caravantechnology.com/%2FCaravan-and-Leisure-In-Car-Charger-P46.aspx (also from Maplins but much much more expensive)

Turn the camera on and it works fine, says on full battery in the 1100d display.

[Psychobilly]

Nice work peeps

Slightly of topic -  With the older batteries the third terminal was "analog"  rather than "digitial"  basically a thermistor was used to measure battery temp to make sure it was in the proper range for charging - not too hot or cold...  the indicated battery level on those was purely a function of the terminal voltage...

The higher end models sulk if they don't see a valid battery and the camera manufacturers are locking out the "serial numbers" used in the cheap clone batteries in camera firmware updates... Without listign it as one of the changes as well...

I have had one of the cheap E-bay camera PSU's explode... fortunately not taking out the camera in the process.. In fact I have had quite a few  cheap Chinese wallwarts go off with a flash and bang so these days I tend not to use the ones supplied and use a decent one instead...

Peter...

[Alien 13]

I am allways super cautious when it comes to cameras and batteries i allways use a battery grip so any mods are done to that i.e. power socket for an external psu plus i also put some protection circuitry in the grip too.

This gives another benifit from removing localised battery heating effects from inside the camera and the external psu is also out of harms way, the battery grip continues to function with batteries as normal when required too.

Alan