Split charge relay, sort of, at Poundland

[Des]

Poundland have golf caddy battery chargers, boot mounting to charge a SLA in car, I've pulled one apart and there's a pretty sophisticated looking circuit, voltage sensing, very generously fused, thermal cut out, something I think is temperature compensation, only 5 amps so not much cop for the heavy stuff, but should be adequate for something like campervans that will drive all day, or I suppose for solar panels.

 

[Station]

What are they meant to charge? (don't say a pound).

[Des]

They're for charging lead acids used in motorised golfing trollies, which save lazy fat bastards having to pull a trolly behind them, apparantly will work with any size battery although I don't suppose the caddy batts would be much bigger than 20AH ish, I'll have to have a play with one, see how it behaves with a big battery.

[lovejoy]

I've got a golf, Des, will it charge that ?? or must I buy it with a charge card ?

no, really, this looks a good piece of kit for a quid, is that black box what it comes in, shown on your car seat ?

I might get one for my MEGA Fiat 900 camper, which at the mo' doesn't even have a leisure battery

( just a cheapo Macro jump start unit,

which is only 17 A/hr, but works for charging up cellfones / running 12v fluorescents, shaving, cooking 3-course dinners, running a dishwasher,

etc. etc. etc.)

[Des]

Yes, the black box is mostly a battery tray with a hold down strap, has a steel base for where it screws to the floor, you can see the little air vent for a great big thyristor and windows for green and red LEDs. The wiring has blue and brown for power in, red / black to aux batt and there's a purple wire to ignore as it's for the interior light to turn off charging when the boot's opened. It's annoying to see something so well engineered for so fickle a purpose.

[lovejoy]

- from an authority in electronics - quote... "Looking at the pcb - which is all I can do, it looks quite expensive! That choke will cost you the best part of £1.00 and is a good indication of the circuit design. Some nice micro-controllers as well I see! We used similar components in our torches. If its got what Des says in the circuitry then it is a well designed unit. 5 amps output is more than enough to trickle charge a battery in good condition. A knackered one is a waste of time and it will put high demands on the charger making it shut down. All these circuits are essential for the proper controlled charged of an SLA Battery - ever seen one explode because of an uncontrolled charge? It's not nice!.

Not too sure about solar panels because of the fluctuation of the input voltage as the sun going in and out. Will need some sort of voltage agc circuit to keep the voltage stable. Here I prefer to use a low output solar panel with a blocking diode in circuit and let the battery itself regulate the trickle charge.

That's about all I can add! For a £1.00 you can't go wrong if you use it for what it was designed - a trickle charger for SLA batteries."