12 volt led lights

[Zac]

Can anyone help me with this problem?  I am replacing the tungsten and flourescent lamps in my caravan with led's as they are less of a drain on the batteries.  The tungsten bulbs are straight forward but the 11inch led tube that  I bought does not have a wiring diagram. I know that the flourescent ballasts should be removed but where do the live and neutral go when there are four terminals? The internet shows various methods which seem to conflict with one another. The led tube I have is an F2458 LED T5.  Thanking you all in the hope of some enlightment.  Zac 

 

[Richard-the-Ninth]

12v does not have live and neutral.

The lamp you mention is 12v not mains.

If you have 12v for your lighting and you have 4 terminals on the lamp you should get a multi meter and see what terminals the LEDs are on. Either that or try it very briefly and see.

If you have mains, you have the wrong lamp.

 

[Andy™]

contact manufacturer / look on their website for wiring instructions

 

[Zac]

Hi to Andy and Richard-the-ninth,  thanks for your inputs. The lamp was bought for me from a marine chandler properly packaged but without a maker's name, so I will use a multimeter and see how I get on . It is definitely 12 volt.  Zac  

 

[SLIPSHOD & SLAPDASH]

12v does not have live and neutral.

The lamp you mention is 12v not mains.

If you have 12v for your lighting and you have 4 terminals on the lamp you should get a multi meter and see what terminals the LEDs are on. Either that or try it very briefly and see.

If you have mains, you have the wrong lamp.

Thats long enough to blow a lot of Led's if the wrong type of driver/supply is used.

 

[Richard-the-Ninth]

Doubtful, since i already mentioned the lamp is 12v, the OP knows its 12v, no driver required, just 12v.

 

[Geoff1946]

Presumably it is the 12volt fittings in your caravan you are replacing. The "Ballast" in these isn't a ballast at all but is an invertor increasing the 12volt supply to around 90volts at a fairly high frequency to strike up the original conventional fluorescent tube. Yes, it must be wired out or would destroy your LED lamp.

The fitting will almost certainly only have one connection to each tube end. The heaters are not used in 12volt invertor systems. That's why the tubes quickly darken at the ends.

The LED "tube" you have bought is presumably designed specifically to retrofit into caravan/boat fixtures, so will surely expect one connection to each end. It would be very difficult to have to rewire the holder in a miniature fitting.

You won't hurt a 12 volt LED lamp by reversing it's supply, (at rated voltage of course). It's a group of diodes and simply won't conduct. Forward biased LEDs emit light.

When I converted my caravan lights I bought LED strip, which you can cut to length, and was much cheaper than conversion tubes. Not much difference in the work to install it, as you have to rewire the fitting anyway.

ps Checking diodes with a multimeter can be confusing. Apart from the forward volt drop of the diode giving strange resistance readings, it's the black probe of the meter which is connected to the +ve of the internal battery. 

 

[Zac]

Hi Geoff 1946, thanks for your information. I will do the same as you have done and use LED strips. 

 

[Geoff1946]

Hi Geoff 1946, thanks for your information. I will do the same as you have done and use LED strips. 

Take care which you buy. Some are much brighter than others. I also recommend the "waterproof" ones, not because your going to get them wet but to have the silicone insulation layer. The uninsulated ones are easily damaged if any metal contacts them causing a momentary short.

 

[Zac]

Thanks again Geoff,  can I ask where you bought your strips from ? 

 

[Geoff1946]

China. Seller Banggood. I've used them quite a bit and found them reliable.

A five metre roll of 50-50 in cool white, (my choice, there are plenty options) for about £6.