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Battery Charger Faq


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What type of batteries do you recommend?

Most of our customers prefer to use deep cycle leisure batteries with their inverters. A few advantages are:

• Delivers higher peak amps faster than conventional batteries

• Provides up to twice the life of conventional batteries

• More consistent voltage across the discharge curve

• Superior cold and hot weather performance vs. conventional batteries


What size battery charger do I need?

To determine the size of charger required you must know there total battery capacity. General rule of thumb is as a bare minimum the charger must be at least 10% the size of the battery so for example a 100AH battery requires at the very least a 10A charger. You cannot buy a charger too large it will just charge your batteries faster.


How long will it take a charger to charge batteries?

It's pretty easy to estimate how long it will take. Simply divide the capacity of the battery by the charge rate of the charger, then increase the amount of time by about 20% to allow for a certain amount of inefficiency. As an example, a battery with a capacity of 100Ah will require about 12 hours to be fully charged by a charger with a charge rate of 10A. (100Ah/10A x1. 2). . Keep in mind that a battery that is only partially discharged will be recharged in less time.

What is a 3 stage battery charger?

The best kind of charger to use on a battery is a 3 stage smart charger. They are easy to use and worry free. They protect you battery from overcharging and can be left connected constantly and prolong the life of batteries.

Stage 1 Bulk –

The primary purpose of a battery charger is to recharge a battery. This first stage is typically where the highest voltage and amperage the charger is rated for will actually be used. The level of charge that can be applied without overheating the battery is known as the battery's natural absorption rate. For a typical 12 volt AGM, the charging voltage going into a battery will reach 14. 6-14. 8 volts, while flooded batteries can be even higher. For the gel battery, the voltage should be no more than 14. 2-14. 3 volts. If the charger is a 10 amp charger, and if the battery resistance allows for it, the charger will put out a full 10 amps. This stage will recharge batteries that are severely drained. There is no risk of overcharging in this stage because the battery hasn't even reached full yet.


Stage 2 – Absorption

Smart chargers will detect voltage and resistance from the battery prior to charging. After reading the battery the charger determines which stage to properly charge at. Once the battery has reached 80%* state of charge, the charger will enter the absorption stage. At this point most chargers will maintain a steady voltage, while the amperage declines. The lower current going into the battery safely brings up the charge on the battery without overheating it.

This stage takes more time. For instance, the last remaining 20% of the battery takes much longer when compared to the first 20% during the bulk stage. The current continuously declines until the battery almost reaches full capacity.


Stage 3 – Float

Some chargers enter float mode as early as 85% state of charge but others begin closer to 95%. Either way, the float stage brings the battery all the way through and maintains the 100% state of charge. The voltage will taper down and maintain at a steady 12. 8-13. 4 volts, which is the maximum voltage a 12 volt battery can hold. The current will also decrease to a point where it's considered a trickle. That's where the term "trickle charger" comes from. It's essentially the float stage where there is charge going into the battery at all times, but only at a safe rate to ensure a full state of charge and nothing more. Most smart chargers do not turn off at this point, yet it is completely safe to leave a battery in float mode for months to even years at a time.


Connecting Batteries Together in Parallel

If your battery application requires more starting power or reserve capacity you can install multiple batteries together in parallel by connecting the like terminals together (positive to positive / negative to negative). Each time you add a battery in parallel you increase the battery Capacity, the voltage remains at 12 volts. For example, two 12V Exide 80AH in parallel will provide 160AH at 12V. Three in parallel provides 240AH and so on . If you have any questions about multiple battery installations, contact us . for further information.


Suggestions for connecting batteries in parallel

• Use batteries of identical make, model, and age.

• Make sure cable gauge is sufficient to handle the higher current flow.

• Prevent cables from shorting (do not allow them to rub against the vehicle body).

• Use only high quality connectors, clean all contacts prior to installation.

• Periodically check all connections for snugness.

• If you are unsure of this procedure, contact us for advice.


Battery installation tips

• Ensure that the battery is properly secured in the vehicle or equipment to prevent movement or vibration wear.

• Do not over tighten the hold down bracket

• Replace any cables and connectors that have corrosion, rust, or other damage.

• Do not install batteries in a non-ventilated or sealed compartment.

• Do not lift or handle the batteries by the terminals.

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Thanks for all that information, brilliant for numpties like me ;)


Would ask the Mod's if this could be pinned :goodpost:




Bailey Pageant Series 6 Champagne 2007    Tow Car Toyota Rav4


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