topic Re: External power supply in Point & Shoot Digital Cameras

External power supply

timgor — Thu, 26 May 2016 17:46:02 GMT

Hello, I have a question about external power supply for Canon powershot cameras.

Regular battey use about 3.6V to power the cameras.

Some cameras can work with external power supply and they rate as 4.3V

First question: 4.3V value sounds very strange to me. Is it made specifically that users would buy only recommended 4.3V adapter and wouldn't buy any other? I tried to measure real voltage and it varies plus minus 0.1V

Second question: What is the top safe voltage that I can use for my camera? Can I use 5V for exmaple? 5V power supply costs $1.

If somebody don't have an answer I can make a test and "fry" my old camera by increasing the voltage.

I know that lowest voltage is 2.3V (2.2V just shut down the camera).

This is question to experienced users, not to officcial Canon representatives

Re: External power supply

Waddizzle — Thu, 26 May 2016 17:53:14 GMT

Experienced users purchase the AC Adapters from Canon.

Re: External power supply

John_ — Thu, 26 May 2016 18:01:28 GMT

lol yeah dont commit PowerShot suicide spring for the Canon power supplies!!

Re: External power supply

timgor — Thu, 26 May 2016 18:17:47 GMT

Are you serious? I should not publish that sort of investigation?

Re: External power supply

timgor — Thu, 26 May 2016 18:24:31 GMT

@Waddizzle wrote:
Experienced users purchase the AC Adapters from Canon.

I understand what you mean. How Canon would explain me why it's real power supply voltage is 4.5V while it says 4.3V?

Re: External power supply

kvbarkley — Thu, 26 May 2016 18:30:09 GMT

Are you testing it loaded or unloaded?

Re: External power supply

Waddizzle — Thu, 26 May 2016 18:33:54 GMT

@timgor wrote:
Bu
@Waddizzle wrote:
Experienced users purchase the AC Adapters from Canon.
I understand what you mean. How Canon would explain me why it's real power supply voltage is 4.5V while it says 4.3V?

Who knows. It could be differences between your measurement methods and theirs. I can think of half a dozen reasons, ranging from rectification to root mean square.

Re: External power supply

timgor — Thu, 26 May 2016 18:36:45 GMT

@kvbarkley wrote:
Are you testing it loaded or unloaded?

What do you mean loaded or unloaded? With zooming and lightning charging?

Re: External power supply

kvbarkley — Thu, 26 May 2016 18:40:25 GMT

If you don't know the answer you should not be playing with it.

A typical digital multimeter has an impedance of millions of ohms, and draws very little current when you make a measurement. Due to its internal resistance a power supply will lower its voltage as the current drawn from it increases.

Your multimeter does not look like the same resistance as the camera so the voltage is higher.

Re: External power supply

Waddizzle — Thu, 26 May 2016 18:40:36 GMT

@timgor wrote:
@kvbarkley wrote:
Are you testing it loaded or unloaded?
What do you mean loaded or unloaded? With zooming and lightning charging?

If you need to ask, then you really shouldn't be bothering with power supplies.

Re: External power supply

timgor — Thu, 26 May 2016 18:51:13 GMT

@kvbarkley wrote:
If you don't know the answer you should not be playing with it.

A typical digital multimeter has an impedance of millions of ohms, and draws very little current when you make a measurement. Due to its internal resistance a power supply will lower its voltage as the current drawn from it increases.

Your multimeter does not look like the same resistance as the camera so the voltage is higher.

Do you really beleive that power nominal voltage has soo deep meaning? usually it has a very flat voltage and slight drop at the full current. But my question was not about it.

My question was why the voltage is so non typical - 4.3V.

Standart adapters have 4.0V 4.5V 5.0V even 4.2V but never 4.3V.

everybody understand that he can take at least lower voltage that is much cheaper than official 4.3V adapter.

Re: External power supply

timgor — Thu, 26 May 2016 18:56:20 GMT

Ok, my last questions is should I publish my results here or I should avoid doing this not to offend somebody from Canon?

Re: External power supply

kvbarkley — Thu, 26 May 2016 19:00:31 GMT

They are pretty loose, you can publish it, but if it gets deleted, don't complain.

And you never can tell with power supplies, many depend on a particular load to put out its rated voltage - which Canon can do since they are camera specific.

You have been spoiled by the tightly regulated USB supplies.

Re: External power supply

timgor — Thu, 26 May 2016 19:10:18 GMT

Ok, I will wait untill get permission from them. I want to be friendly.

Another question: can I read something about the third (middle) electrode of battery? How it measures the battery temperature and how does the camera regulates it. I notised that when I have extreme temperature (for example in a hot day in a closed car) - camera shuts down on itself. That means it has overheating protection. I would like to know more details and more numbers about it.

Re: External power supply

kvbarkley — Thu, 26 May 2016 19:13:14 GMT

That is an internal Canon thing, We have no info on that, but I suspect it is more than just temperature, (i.e., it is a serial connection to an internal microcontroller on the battery.) I think it also keeps track of charge/recharge cycles and the state of the batteries charge.

Re: External power supply

timgor — Thu, 26 May 2016 19:19:31 GMT

@kvbarkley wrote:
That is an internal Canon thing, We have no info on that, but I suspect it is more than just temperature, (i.e., it is a serial connection to an internal microcontroller on the battery.) I think it also keeps track of charge/recharge cycles and the state of the batteries charge.

I expected that nobody know and nobody really need this information. Just interesting...

official canon power supply has just two electrodes so it must work in a different way than battery. It would be interesting if it still shut down in case of extreme temperature with the extwernal power supply. If yes than what is the maximum temperature in both cases. Does it have some other temperature sensors inside the camera?

Re: External power supply

kvbarkley — Thu, 26 May 2016 19:21:59 GMT

Yes, because they monitor the temperature of the sensor during video.

Re: External power supply

timgor — Thu, 26 May 2016 19:30:19 GMT

@kvbarkley wrote:
Yes, because they monitor the temperature of the sensor during video.

During video? It's a new information for me. Can you please explain, does it monitor and protects camera (shut down) during video only or it's monitoring temperature constantly but it overheats especially during video?

Do you understand what I mean?

In other words if I don't run video will it shut down anyway if it would reach some maximum temperature?

Re: External power supply

kvbarkley — Thu, 26 May 2016 19:50:50 GMT

I believe it is for live view in general, not just shooting video, but I am not a Canon Engineer.

Re: External power supply

timgor — Thu, 26 May 2016 20:03:13 GMT

@kvbarkley wrote:
I believe it is for live view in general, not just shooting video, but I am not a Canon Engineer.

Sounds like reasonable, anyway I will publish my results here If I measure this. i think there is no chance to get this information from engineers.