Electronics 2000

Hopefully this will be an easy question for someone. I am an absolute novice when it comes to electronics. The problem is I have mixed up two power supply units - one recharges the battery on my cordless hedge trimmer, the other recharges my car jump start system (one of those gadgets that has jump start, air compressor, light etc). The 2 psu's are identical apart from one being bulkier than the other and one is rated 400mA whilst the other is 500mA - both are same voltage (15V I think from memory) both positive inner. The rechargeable battery for the hedge trimmer says its 12v 1.7Ah and charge for 5hr. Which psu belongs to which gadget, or will it not matter if I get them the wrong way round?

Hi

I think the 400mA charger is for the hedge trimmer - the battery capacity suggests this should be correct. If, as you say, the voltages and connector polarities are the same (and both are DC) it shouldn't matter using the 500mA one for the hedge trimmer either, but might matter using the 400mA one for the jump starter.

These chargers are normally just DC power supplies; the charging circuitry being built into the equipment. As long as the current capacity of the power supply is equal or greater than that required by the equipment it is powering there shouldn't be a problem.

Do double check the voltages first though!

meh sould work both ways it to small to do any problems