Manual Battery Chargers
Manual chargers are great to use for when your battery voltage is too low for an automatic charger to work properly or for heavy duty commercial use, but they cannot be used as a maintainer. Do not leave a manual charger on a battery for an extended period of time after the battery is completely charged up. A manual charger will not stop charging or go into a float mode after the battery is fully charged. You can damage a battery if you continue to put voltage or amperage into it when it is already completely charged.