Testing my battery conditioner

[Norfolkandchance]

Hi,

I have combined battery charger / conditioner. It is supposed to charge the battery and then keep it topped-up. I've never used it to top up before.

It works as a charger - I attach it to a car with a flat battery and the battery will charge. However, it has LEDs which are supposed to indicate when it switches to battery conditioning. After 3 days the LEDs havn't changed. I have a multimeter but no idea what to do with it - how can I check if it is keeping it topped up and not overcharging.

Thanks

[andyiley]

If it still thinks it is charging after 3 days, either the conditioner or the battery is goosed.

Either get the battery drop tested, or try a different battery.

[AW10]

A fully charged healthy battery should show in the region of 12.5-12.8 volts. If you turn the charger off what is the voltage at the battery? And then wait an hour and test again? And what does it show when the charger is allegedly charging the battery rather than maintaining it?

[Norfolkandchance]

Thansk for the replies.

I should have said that after a few hours on the charger a slightly flat battery show all the signs of being perfect. The battery is only about 6 months old, and is a good make, and hasn't ever fully discharged. Once charged it then keeps its charge for a long time - can start the car 3 or 4 weeks later - so I have no concerns about the battery.

Either the LEDs on the charger are not indicating when it switches to conditioner or the charger isn't switching. The LEDs don't seem to work when it is charging either - the wrong one lights up. From memory they never did but since it charged OK I didn't worry as I didn't need it as a conditioner when I first bought it.

I wondered if there is anyway I can test the output from the the charger and see if it has switched modes.

[Locknut]

You can test it with an ordinary volt meter (or your multimeter set to DC Volts). I have not checked the manual of my unit so I can only quote round figures: the unit will charge the battery until the voltage reaches 14-ish, it then pauses until the voltage decays to 12-ish and starts charging again. My unit also has settings for three different types of battery or temperature and the correct one should be selected.