#1  
Old 05-12-2009, 04:39 PM
pjphilli (Peter)
Registered User

pjphilli is offline
 
Join Date: Jan 2008
Location: Thornleigh Sydney
Posts: 613
Canon camera battery

Hi

I have a Canon 400D with a battery pack type NB-2LH.
The battery has three terminals. The outer ones are marked +ve and -ve
and the normal about 8 volts appear across these. However, there is a third (middle) terminal which appears to be at the same potential as the -ve terminal. What is the function of this middle terminal? I suspect it is a battery charge sensing function that the camera recognises.

The reason I am asking is that I have a 240 power pack which is specific for the Canon 400D and which delivers the required approx 8 volts to the + and - terminals as above. I have checked that this is so when the power supply plug is inserted in the back of the section which slides into the Canon like an ordinary battery. I have ensured that the power supply plug sits fully in when the insert is in the camera. However, the camera does not switch on. I notice, however, that bench tests show that the middle terminal of the slide in section is open circuit (ie no connection with the -ve terminal as per the normal battery). Is this my problem?

Cheers Peter
Reply With Quote
  #2  
Old 05-12-2009, 05:37 PM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,891
The third terminal is temperature sensor which charger recognises, not the camera.
So it should be OK to provide just +8V to camera..
Pay attention to switch, which is activated when battery is in place and the lid is closed, this may be your problem.

Having said that, I know that some mobile phones ( I used to work for NEC-A in mobile division) need to have resistor of specific value between GND and third terminal, so phone thinks it has battery inserted.
I think people have used power adapter with 400D without problems.

Last edited by bojan; 05-12-2009 at 06:59 PM.
Reply With Quote
  #3  
Old 05-12-2009, 07:26 PM
mswhin63's Avatar
mswhin63 (Malcolm)
Registered User

mswhin63 is offline
 
Join Date: May 2009
Location: Bertram, Western Australia
Posts: 3,327
I haven't a lot of experience in high DSLR's but do they have an external DC supply socket and maybe would be easier to place external battery pack to match the DC input jack. I would be like continually charging the internal battery.

Only a thought but it is a way I have done things on other electronic equipment to extend battery life.
Reply With Quote
  #4  
Old 05-12-2009, 08:17 PM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,891
Quote:
Originally Posted by mswhin63 View Post
I haven't a lot of experience in high DSLR's but do they have an external DC supply socket .
Canon 400D does not have separate power socket.
Reply With Quote
  #5  
Old 06-12-2009, 09:48 AM
pjphilli (Peter)
Registered User

pjphilli is offline
 
Join Date: Jan 2008
Location: Thornleigh Sydney
Posts: 613
Thanks Bojan for solving the mystery of the third battery terminal which I can eliminate from my investigation of the problem. I agree Malcolm that a simple side entry power socket would be better than the rather clumsy substitute battery arrangement. I suppose with the plethora of sockets already around the 400D that Canon did not wish to confuse the situation further. Maybe my difficulty is a simple contact problem which I will investigate further.
Cheers peter
Reply With Quote
  #6  
Old 06-12-2009, 02:08 PM
pjphilli (Peter)
Registered User

pjphilli is offline
 
Join Date: Jan 2008
Location: Thornleigh Sydney
Posts: 613
Hi - I just had another good look at the Canon powered battery adaptor and noticed that the -ve terminal seemed to be intermittent. So I cut the top of the adaptor using a fine hacksaw and my problem was revealed. The power socket -ve terminal had not been soldered to the lug (like the positive) but the lead just pushed through it. A bit of soldering and sticking the top back on with araldite has solved my problem. This stuff made in China may be cheap but you wonder about the quality control!
Cheers Peter
Reply With Quote
  #7  
Old 06-12-2009, 03:39 PM
mswhin63's Avatar
mswhin63 (Malcolm)
Registered User

mswhin63 is offline
 
Join Date: May 2009
Location: Bertram, Western Australia
Posts: 3,327
It is a bit concerning that high end equipment is using low end manufacturing method and using their name to boost prices.
Unless it is an after market product!

Glad it is sorted.
Reply With Quote
  #8  
Old 06-12-2009, 04:07 PM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,891
Quote:
Originally Posted by mswhin63 View Post
It is a bit concerning that high end equipment is using low end manufacturing method and using their name to boost prices.
Unless it is an after market product!

Glad it is sorted.
This is the trend today, everywhere.
It is all about profit (both for manufacturer and buyer.. everyone wants to reduce cost).
Not that this bothers me too much.. after all, today's products have very short life anyway.. becoming obsolete sometimes even before they reach the market.
The cost of manufacturing today is the question of life or death for many companies.. even if the quality of the product is the victim.
DIY skills are becoming essential in such environment :-)
Reply With Quote
  #9  
Old 07-12-2009, 03:14 PM
pjphilli (Peter)
Registered User

pjphilli is offline
 
Join Date: Jan 2008
Location: Thornleigh Sydney
Posts: 613
Thanks for your further comments. I cannot complain as I bought the Canon adaptor at a very reasonable price from a US supplier. Fortunately, I have electronic skills so I was able to do the repair myself.
Pity the poor purchaser who would have been faced with the cost of returning the item. In fixing gear over the years I have noticed that the high end electronics (eg in this case the power supply itself) are usually not at fault but very often connecting leads and their associated plugs/sockets. For example, I had trouble with my HEQ5Pro connecting cable which I was able to replace locally with a Cat 5e patch lead (cost $5.25!). Cheers Peter
Reply With Quote
  #10  
Old 07-12-2009, 05:46 PM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,891
Quote:
Originally Posted by pjphilli View Post
In fixing gear over the years I have noticed that the high end electronics (eg in this case the power supply itself) are usually not at fault but very often connecting leads and their associated plugs/sockets. For example, I had trouble with my HEQ5Pro connecting cable which I was able to replace locally with a Cat 5e patch lead (cost $5.25!). Cheers Peter
This is because the electronics itself is machine assembled, while cables etc are done with (cheap => un-skilled) human labour.. and this is where the problems start..
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 09:11 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Lunatico Astronomical
Advertisement
SkyWatcher Australia
Advertisement
NexDome Observatories
Advertisement
Celestron Australia
Advertisement
Meade Australia
Advertisement
OzScopes Authorised Dealer
Advertisement
Astronomy and Electronics Centre
Advertisement