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Power Supply providing inadequate power to portable video camera (Trek2000's Ai-Bal)

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neko_whisker

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Hi I have problem getting the power supply to provide the power to Ai-Ball. Ai-Ball use CR07 Lithium Battery, however the battery is used up in one and half an hour.
So I decided to use the DC Lab power supply so that the Ai-Ball can be used longer.
I set the power supply to DC3V according to the battery's voltage rating. I can't seem to get the camera working.

Do you have any idea where I went wrong?

If I can measure the working current of the battery for the camera, how do I set the current at the DC3V of the Power supply?

Clement
 

KerimF

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If I can measure the working current of the battery for the camera, how do I set the current at the DC3V of the Power supply?
Clement
First you need to measure the voltage (not current) of the battery.
It will be good if you can measure also the current that your camera needs from your battery (when it is most active).

Then a suitable power supply should have a rather constant voltage (close to the battery voltage) for a zero current (open circuit) up to the maximum current that is required by the camera.

Note:
Many power supplies may have the same regulated voltage but the maximum current which they can deliver (without their voltage drops appreciably) might be very different. That is why a PS is characterized also by its maximum current and/or power (V * I).

Kerim
 
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neko_whisker

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Hi Kerim,
Just as I followed your suggestion.
I connect the camera to power supply at 3v (similar to battery)
I then measured voltage across the terminal points of the power supply and adjusted until it is 3.0 to 3.5 DCV.
The camera is powered on but it is not getting hotter and I can see that max current as viewed on the power supply.
I tested the camera by checking it's WIFI signals on my computer so that I can see the video wirelessly.
But it is not.

So when I changed back to battery, it gets hotter and I can see the video signal and the wifi is detected.

I am still puzzled as to how to get the camera working with power supply. Is that because the current is insufficent?

Why does it get hotter? Is that because the current obtained from the battery is different from the power supply even thought both use 3VDC?

Please advise

Clement
 

KerimF

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If there is a ripple on the 3V DC external supply... this may be the cause. It happens once to me that a ripple of about 300mV peak-to-peak the set refused to work.
Sometimes we can have an idea about the amplitude of the ripple by using a voltmeter set for AC voltage (in this case it blocks the DC and passes the AC part only).

Added:
Of course, the AC measurement (on the 3V DC) should be made with load (camera on).
 
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