Battery Eliminator project

ZeroID (Brent) · #1 25-09-2016, 06:48 AM

Rainy day project.
I decided to make up a battery eliminator for the 450D. I've got a suitable wall wart ( 7.2v dc ) and was pulling apart one of the old batteries to modify as a connector for the external supply.
The battery still had some life and I was checking which connection was which and noticed it had a small circuit board inside and three links to the battery. This appears to be a mid voltage connection providing about 3.6 volts and is present on the centre pin of the connector.
I had assumed I only needed the 7.5 v to run the camera. Is this extra voltage required or is it a battery check to ensure the right parts are used?

glend (Glen) · #2 25-09-2016, 07:02 AM

I will check my Orion battery eliminator and get back to you. However a quick Google search of "Canon 450d voltage supply" shows a number of previous forum threads discussing this topic and supply, seems 7.4v is all that is needed. Check by reading some of those threads, including one on iis.

julianh72 (Julian) · #3 25-09-2016, 09:19 AM

The third terminal is usually for a thermistor which is used to regulate the battery charging rate to avoid cooking the battery. You will probably find that the voltage varies with the battery temperature.

ZeroID (Brent) · #4 25-09-2016, 06:25 PM

Many thanks both of you, Project will now continue ....

bojan · #5 26-09-2016, 10:13 AM

After even designing 3D-printable battery mockup, I decided it is not worth the effort.. and I simply bought it from ebay, see here.

mswhin63 (Malcolm) · #6 26-09-2016, 01:51 PM

Quote:

Originally Posted by bojan

After even designing 3D-printable battery mockup, I decided it is not worth the effort.. and I simply bought it from ebay, see here.

I agree, th cost of the eliminators from ebay sometimes just make it not worth the effort.

I made mine about 3 years ago and yesterday cleaned out my crate. I also used a simple regulator from Jaycar to power it. I modified the regulator to get the voltage at a more accurate level.

ZeroID (Brent) · #7 27-09-2016, 09:33 AM

I just have to stick a couple of wires inside it, I have a suitable wall wart @ 7.2volt, fell off a truck ... ( Work throw out actually ). I have a few more to play with.

Rainy Day project, money has nothing to do with it. Looks like I will need a few more RD projects, this cloud\rain problem is forecast to last a a week or more still. Haven't seen clear sky for nearly a month now.

I'll have a go at cleaning the 450D sensor next, it will take me a month to clean the garage first for a clean area.

Should keep me busy ....

rcheshire (Rowland) · #8 01-10-2016, 06:00 PM

I use an 8V regulator in a battery grip. Supply voltage range, without running outside to look, 7.4 ~8.1V ~1A. It doesn't need to be exact.

silv (Annette) · #9 01-10-2016, 06:26 PM

a benefit is or would be that the battery compartment is open and EMPTY, except for the wires.

less heat = less noise.
I think the ebay ones still stick something massive into the camera body, tight?
So your idea is actually a tick better for AP, Brent

bojan · #10 01-10-2016, 06:47 PM

Quote:

Originally Posted by silv

...
I think the ebay ones still stick something massive into the camera body...

Only battery enclosure, but empty... and wires

ZeroID (Brent) · #11 02-10-2016, 06:35 PM

I think that 3.5 volt centre link is required for some reason. I've got 7.5 Volts across the two outer pins ( and in the correct polarity ) but camera will not turn on. Works ok on the remaining battery still. Have to investigate further.

bojan · #12 02-10-2016, 06:39 PM

Quote:

Originally Posted by ZeroID

I think that 3.5 volt centre link is required for some reason. I've got 7.5 Volts across the two outer pins ( and in the correct polarity ) but camera will not turn on. Works ok on the remaining battery still. Have to investigate further.

I remember a discussion on CN, it may be a resistor.
I have that eliminator, I will check it for you.

bojan · #13 02-10-2016, 06:52 PM

It seems middle pin is open.

Shano592 (Shane) · #14 02-10-2016, 06:53 PM

Forgive me for intruding on the thread.

Many of the Canon DSLRs have a little trip switch at the battery housing. If the battery housing lid is removed, and nothing is there to trip the switch, then the camera will not activate. Everything else can be perfect, but nothing will happen.

First hand experience on this one.

I'm not sure of your setup, so just throwing it out there.

bojan · #15 02-10-2016, 06:58 PM

Yep.. and door must be closed as well.

ZeroID (Brent) · #16 02-10-2016, 07:07 PM

Door closed, I'll check for a trip switch for the battery housing. Also do a centre pin voltage check on the other battery.
Tomorrow .. Following WRC at present in Corsica.

Cheers both ...

Shano592 (Shane) · #17 02-10-2016, 07:39 PM

The first time I used the battery grip, I forgot to put the battery door back on after taking the battery grip away. Lesson learned.