I have a Selmar Turbo 6 12v Battery Charger, but no instructions
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We today have two types of lead acid batteries, flooded, which means you can top it up with distilled water, and the Absorbed glass mat (AGM) also called Valve regulated lead acid (VRLA) and the latter type can't be topped up, so you need a special battery charger which can not over charge them.
Your battery charger can only be used with the flooded type, were you can remove caps and top up each cell.
These
both from Lidi, cost around £15, so in the main not worth giving the old charger shelve space. Except for one safety feature on the new chargers, which can cause problems, they are designed to be fool proof, and one of the features is they will not turn on if leads are the wrong way around.
This same feature, means a 6 volt battery will not charge if completely flat, and a 12 volt one, not under 7.5 volts, as it thinks it's a 6 volt battery. The old charger will still charge completely discharged batteries, but often no safety to stop overcharging.
If a battery has a shorted cell, the a 12 volt battery is really a 10 volt battery, and so any battery charger will over charge them. With a pair of 35 Ah batteries, one shorted cell, got them hot enough to warp the plastic, this happened with my mobility scooter.
As to charging a battery which has completely discharged, seen one sit for two weeks doing nothing, then fully recharge, so my method is to put it in parallel with another battery, and plug the charger into an energy monitor, so I can see what it is doing from my computer or phone.
The grey 3.8 amp charger will charge a 110 Ah battery, the new 5 amp version is faster, but not by that much, as soon at battery voltage hits 12.8 volts charge rate drops to 3 amp on both. So that 110 Ah battery looking at 40 hours, or 2 days.
This is the problem with the old charger, can't really leave them a week unattended, where the new type you can.
Mine will charge until 14.4 volts then switch off until volts drops to 12.8 volts then switch on again, so I could leave it on the battery for months with no harm, the old type you need to measure the s.g. with a hydrometer to ensure not over charged. In this country around 1.28 is fully charged, but in hot countries we use a lower sg, so the sg reading is not that accurate, and has to be done at 20°C. If not you need a correction chart, and it depends on what glass the hydrometer is made from, so a Pyrex will hardly change with temperature but other glass with change a lot.
Your battery charger can only be used with the flooded type, were you can remove caps and top up each cell.
These
both from Lidi, cost around £15, so in the main not worth giving the old charger shelve space. Except for one safety feature on the new chargers, which can cause problems, they are designed to be fool proof, and one of the features is they will not turn on if leads are the wrong way around.This same feature, means a 6 volt battery will not charge if completely flat, and a 12 volt one, not under 7.5 volts, as it thinks it's a 6 volt battery. The old charger will still charge completely discharged batteries, but often no safety to stop overcharging.
If a battery has a shorted cell, the a 12 volt battery is really a 10 volt battery, and so any battery charger will over charge them. With a pair of 35 Ah batteries, one shorted cell, got them hot enough to warp the plastic, this happened with my mobility scooter.
As to charging a battery which has completely discharged, seen one sit for two weeks doing nothing, then fully recharge, so my method is to put it in parallel with another battery, and plug the charger into an energy monitor, so I can see what it is doing from my computer or phone.
The grey 3.8 amp charger will charge a 110 Ah battery, the new 5 amp version is faster, but not by that much, as soon at battery voltage hits 12.8 volts charge rate drops to 3 amp on both. So that 110 Ah battery looking at 40 hours, or 2 days.
This is the problem with the old charger, can't really leave them a week unattended, where the new type you can.
Mine will charge until 14.4 volts then switch off until volts drops to 12.8 volts then switch on again, so I could leave it on the battery for months with no harm, the old type you need to measure the s.g. with a hydrometer to ensure not over charged. In this country around 1.28 is fully charged, but in hot countries we use a lower sg, so the sg reading is not that accurate, and has to be done at 20°C. If not you need a correction chart, and it depends on what glass the hydrometer is made from, so a Pyrex will hardly change with temperature but other glass with change a lot.
