Too much battery

[AllisonJ]

My brother plugged a 12V 7Ah battery into his game cam's external 12V power supply port and the cam became instant toast with associated smoke. He's used the 7Ah battery on other game cams without problem. The blown cam reqiures 8 AA batteries or the manufacturer's power supply if the external port is used. I can only guess that the circuitry's resistance properties couldn't handle the additional current capacity of the battery, Can some enlighten me on this.

 

[duke37]

The device will take only the current that it needs as long as the supply is 12V. It doesn't matter where it comes from.

My guess is that you connected it the wrong way round, that is a sure way to disaster.

 

[AllisonJ]

Of course, one would certainly think that. However, it did happen. And, the only way that the battery could have been miss connected would be if the little 5mm plug that connects to the camera required center negative polarity. We assumed that the outside housing barrel to be negative and connected it to the battery accordingly.

 

[(*steve*)]

Measure first...

 

[davenn]

We assumed that the outside housing barrel to be negative and connected it to the battery accordingly.

NEVER assume anything ... it can lead to costly mistakes

As steve said always measure first

Dave

 

[duke37]

Older equipment often had central pin negative. It is now more common to have the central pin positive. There is often a little diagram on the equipment to show the correct connection, you may need a magnifying glass to see this.

Did you check the 'official' power supply for polarity?

 

[AllisonJ]

measure ?? How do you measure what the device itself requires for polarity on it's external 12V input port.? There is no designation or info written on the port Of course, we confirmed that the plug from the battery hookup was connected center positive to the plug with a voltmeter. The external power-in port is electrically isolated from the AA battery pack so it's useless to check anything there. Without disassembling the unit, there's nothing externally that's conductive to verify circuit board ground with the plug-in port.

 

[duke37]

If you have a power supply to go into the 12V input port, you can determine the polarity. Alternatively, find the users manual or contact the makers.

Is the battery pack inside the camera?
Does the camera have two inputs?
How about a sketch of the bits you have and how they are connected?

 

[AllisonJ]

The attached pic show the simple battery hookup to the cam. I added the cam manufacture's description of the battery and solar setup as a 12V system. Also, I included the back of the batt pac, and after looking at it, realized that it's comprised of two 6V banks in parallel- no 12V is sight. Talking to the maker's Ist tier interface would be a waste of time. They wouldn't be concerned about anything that might circumvent an overpriced accessory sale. I'm ready to lay this problem to rest and simply stay with the batt pac setup. Thanks for your input.

 

[(*steve*)]

measure ?? How do you measure what the device itself requires for polarity on it's external 12V input port.?

Several ways.

The easiest is to get the regular poser supply and probe it with a multimeter.

Another way is to look for a symbol (on either/both) the equipment or the power supply designed for it. (Normally you look on the equipment first.

Lastly, you can open up the equipment and either trace the wiring or measure voltages while it's powered up.

 

[CDRIVE]

Are you saying that the cam survived the over voltage and is still functioning off the battery pack?

Chris