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Hello

We (Dulas) used to sell small 12V LED bulbs with standard Edison Screw or bayonet bases. Combined with some festoon fittings (the ones that clamp on to flat cable) and a bit of 2.5 flat twin cable, connect to a small deep cycle or leisure battery via a fuse and charge it either every few days from a generator or with a small PV panel and charge controller. These LED lights were 1 watt or less so minimal current > low cable volt drop and small battery capacity required. The battery and any PV rig would need to be secure but could be a short distance away. Bulbs would still be nickable but not much use on thier own.

As a rule of thumb, work out total lighting power in watts, divide by 12 for current in amps (assuming a 12V system), multiply by cable length (one way) in metres and divide by 10 to get the cross sectional area of the cable for acceptable volt drop, eg 10 no. 1 watt bulbs = 10 W / 12 ~ 1 amp x 25 metres of cable / 10 = 2.5 sq.mm twin cable.

I'll ask at work if these bulbs or anything similar are still available. Another possibility would be to get some LED fairy lights. Get the ones with a 12V transformer (you don't need all the flashing programs though). Ditch the tx and connect to a battery as before. Cheap and cheerful. I've used a similar approach at parties and festivals many times. I've got some green ones in my camper that have a built-in miniscule PV and a couple of AA NiMH batteries - bit dim but enough to see where to put your feet.

Good luck,

Duncan

Hello

We (Dulas) used to sell small 12V LED bulbs with standard Edison Screw or bayonet bases. Combined with some festoon fittings (the ones that clamp on to flat cable) and a bit of 2.5 flat twin cable, connect to a small deep cycle or leisure battery via a fuse and charge it either every few days from a generator or with a small PV panel and charge controller. These LED lights were 1 watt or less so minimal current > low cable volt drop and small battery capacity required. The battery and any PV rig would need to be secure but could be a short distance away. Bulbs would still be nickable but not much use on thier own.

As a rule of thumb, work out total lighting power in watts, divide by 12 for current in amps (assuming a 12V system), multiply by cable length (one way) in metres and divide by 10 to get the cross sectional area of the cable for acceptable volt drop, eg 10 no. 1 watt bulbs = 10 W / 12 ~ 1 amp x 25 metres of cable / 10 = 2.5 sq.mm twin cable.

I'll ask at work if these bulbs or anything similar are still available. Another possibility would be to get some LED fairy lights. Get the ones with a 12V transformer (you don't need all the flashing programs though). Ditch the tx and connect to a battery as before. Cheap and cheerful. I've used a similar approach at parties and festivals many times. I've got some green ones in my camper that have a built-in miniscule PV and a couple of AA NiMH batteries - bit dim but enough to see where to put your feet.

Good luck,

Duncan

the LED bulbs I was referring to - see attached. They cost about 10 Euros. A possible supplier in that neck of the woods (well, Sierra Leone) might be

Mike and Clive Dawson, CEC Engineering (UK) 01342 315935 (SL) 00 232 76 734735 mikedawson@cecengineering.org.uk clive@cecgroup.org.uk

I don't know them personally, but colleagues have done so for many years and recommended them. Alternatively, we could ship some out with a PV panel, controller and battery if required.

I suppose they still might get pinched but a bulb on its own is a lot less attractive than a complete unit with it's own panel and battery. They could be fitted in vandal-proof bulkheads or something for more protection from casual pilfering.

Hope it's useful,

Duncan

Hello

We (Dulas) used to sell small 12V LED bulbs with standard Edison Screw or bayonet bases. Combined with some festoon fittings (the ones that clamp on to flat cable) and a bit of 2.5 flat twin cable, connect to a small deep cycle or leisure battery via a fuse and charge it either every few days from a generator or with a small PV panel and charge controller. These LED lights were 1 watt or less so minimal current > low cable volt drop and small battery capacity required. The battery and any PV rig would need to be secure but could be a short distance away. Bulbs would still be nickable but not much use on thier own.

As a rule of thumb, work out total lighting power in watts, divide by 12 for current in amps (assuming a 12V system), multiply by cable length (one way) in metres and divide by 10 to get the cross sectional area of the cable for acceptable volt drop, eg 10 no. 1 watt bulbs = 10 W / 12 ~ 1 amp x 25 metres of cable / 10 = 2.5 sq.mm twin cable.

I'll ask at work if these bulbs or anything similar are still available. Another possibility would be to get some LED fairy lights. Get the ones with a 12V transformer (you don't need all the flashing programs though). Ditch the tx and connect to a battery as before. Cheap and cheerful. I've used a similar approach at parties and festivals many times. I've got some green ones in my camper that have a built-in miniscule PV and a couple of AA NiMH batteries - bit dim but enough to see where to put your feet.

the LED bulbs I was referring to - see attached. They cost about 10 Euros. A possible supplier in that neck of the woods (well, Sierra Leone) might be

Mike and Clive Dawson, CEC Engineering (UK) 01342 315935 (SL) 00 232 76 734735 mikedawson@cecengineering.org.uk clive@cecgroup.org.uk

I don't know them personally, but colleagues have done so for many years and recommended them. Alternatively, we could ship some out with a PV panel, controller and battery if required.

I suppose they still might get pinched but a bulb on its own is a lot less attractive than a complete unit with it's own panel and battery. They could be fitted in vandal-proof bulkheads or something for more protection from casual pilfering.

Hope it's useful,

Duncan