All major starter battery manufacturers recommend maintaining such batteries FULLY CHARGED during periods of non-use.

OptiMate III is totally safe for months-long connection and maintenance or irregularly or seasonally used batteries even while still connected to the vehicle, No risk of over-charging.

Electronically protected against user errors. Just connect the OptiMate III to your battery, the rest is automatic. There is no switch, no-fuse... and there are no sparks. De-activates automatically if conections are broken.

Tests the battery for possible deep discharge or sulphation. If necessary, the OptiMate III automatically engages a special high voltage recovery mode ( up tp 22v ) with controlled very low fixed current, so as to desulphate very flat batteries, for up to 2 hours, controlled by internal timer.

Charges at 0.6 Amps constant current ( stage ) for maximum safe rate recharge until such time as the battery is normally able to crank the engine.

During a 30 minute timed verification stage the OptiMate III ensures that even well-used batteries are brought to full charge saturation. If necessary the programme reverts automatically to the bulk charging stage, repeating steps 2 & 3 as many times as may be necessary until the battery is thoughly charged.

During a times 30 minute pause in its programme, the circuit monitors the battery's voltage retention when . This is to identify batteries unable to retain their charge adequately without charger support. ( The charge LRD continues to indicate).

The green LED indicates for batteries which pass the voltage retention test. They are then offered charge current according to need for 30 minutes so as to support connected electronic alarms or other small loads. The voltage retention check (step 4) is then repeated and alternates thereafter with step 5 for as long as OptiMate III and battery remain connected. Suspect batteries are identified by the red LED indicating. The circuit will continue to offer the battery float charge support until disconnected.