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What size SLA Charger do I use for 17Ah Batteries
I'm looking to use your MFA 12V 500mA SLA charger on a 17Ahr sealed battery. as there is no range of battery capacity stated, will this be ok with this size battery?
Post Number: 94
For sealed lead acid batteries, the maximum charging current must not exceed 25% of the Ah capacity. So, for a 17Ah battery, the maximum charging current must be less than 4.25A.
However, if the available charging current is too low in relation to the Ah capacity, the charging time will be long. At 500mA, it could take as long as 40 hours to charge a flat battery. It is also possible that too low a charging current will not even start the charging process on a deep discharged battery.
We would strongly recommend one of out Mascot 2.7Ah chargers 1070-001) that will fast charge the 17Ah battery and automatically switch to trickle charge so as not to damage the battery by over-charging. In fact, the charger can be left on trickle mode indefinitely thus ensuring the battery is kept at peak charge.