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The easy fix is to use a normal filament lamp bulb.
The spec says 10v at 1.3W which could be awkward so I would suggest something like a 12v bulb at 1.2 to 1.4W but a 9v 1.4w bulb could be OK :?
Your 10v bulbs will be wired in series of 24 bulbs across a high (mains 240v) voltage, typical christmas tree style.
If any one bulb fails the whole string would go out so the manufacturers use special bulbs which go short-circuit when the filament fails. This is OK if just one bulb fails (giving 240v/23 bulbs = 10.44v) but if a second one goes the problem worsens to 10.9v per bulb. Eventually this over-running causes further failures and the whole string goes dead-short across the mains :shock:
By fitting one so-called fuse bulb (a normal filament lamp), if this blows the whole string is safely killed - you know (in theory!) that this is the cause of the string failing so is easily found and fixed.
All you need then is a bulb that will run on the 10v, 1.3W (0.13A) that is available without being over-run (too bright) so that there is a point in the circuit that can fail open circuit (a fuse). 12v 1.5W may be dimmer than the other bulbs but could be easy to find and cheap :wink:
There are actually 27 bulbs in the chain. This workes out at 8.89V per bulb.
mechie said:
If any one bulb fails the whole string would go out so the manufacturers use special bulbs which go short-circuit when the filament fails. This is OK if just one bulb fails (giving 240v/23 bulbs = 10.44v) but if a second one goes the problem worsens to 10.9v per bulb. Eventually this over-running causes further failures and the whole string goes dead-short across the mains :shock:
By fitting one so-called fuse bulb (a normal filament lamp), if this blows the whole string is safely killed - you know (in theory!) that this is the cause of the string failing so is easily found and fixed.
If one bulb goes out (fuse or ordinary) the whole lot go out.
mechie said:
All you need then is a bulb that will run on the 10v, 1.3W (0.13A) that is available without being over-run (too bright) so that there is a point in the circuit that can fail open circuit (a fuse). 12v 1.5W may be dimmer than the other bulbs but could be easy to find and cheap :wink:
It looks like a fairly standard christmas tree light fitting, you may be able to get replacements at a lighting outlet - although you will probably have to ask.
But probably the first place to look is where you bought them from, they should be able to help you - either by sourcing the bulbs for you, or giving you details of where you can get them from.
It looks like a fairly standard christmas tree light fitting, you may be able to get replacements at a lighting outlet - although you will probably have to ask.
I did ask at my local electrical and lighting shop and they said they cant get that particular fitting.
Nigel Goodwin said:
But probably the first place to look is where you bought them from, they should be able to help you - either by sourcing the bulbs for you, or giving you details of where you can get them from.
I don't know how it's done there in the UK, but over here, we just use a replacement bulb with the right specs and swap it into the plastic base. The replacement bulbs themselves have no bases -- they are simply wire terminal type bulbs similar to the ones shown here, except that they are about 20mm long with a pointed tip to the envelope. We simply straighten the wire terminals on the dead bulb and pull it from the base. The new bulb gets slid into the base, with its wire terminals aligned with the holes in the base. Bend the wires over the base to complete the swap.
In that way, the base style becomes irrelevant -- all that matters is the actual bulb specs.
As the retailer they have the same responsibilities as any other retailer, being a supermarket doesn't alter that in any way. They should be able to either supply you with bulbs, or put you in touch with someone who can, they have an obligation to do this!.
I would expect a large concern like Safeway to have systems in place, even if it's only giving you your money back.
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