Lamp fitting and cable failure

royfellows

Well-known member
This applies to all lamps, mine and others, hence a general posting. I feel a need to raise awareness of this issue.
If something is put under stress it will fail.

The picture below shows how this comes about in a lamps fitting and the point of failure. If the cable is flexible rubber sheathed it will be the internal wires that will fail through metal fatigue, if the cable is the harder PVC failure will occur by the splitting of the outer sheath.

I changed my lamps to the type of gland which provides cable support a while ago for this reason.
 

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aricooperdavis

Moderator
Well worth thinking about how it's mounted on your helmet to reduce flexing in that cable! What sort of protective gland thing are you using, Roy?
 

royfellows

Well-known member
They are from Lapp Kabel and purchased from Farnell # 1204195
IP68 rated. I buy in quantities of about 100 and this gets the price down to less that I was paying for the Chinese metal ones!

Warning about Chinese stuff is same product gets made by different factories with vastly different quality standards, and this across the board from electronics to wellies.

Anyway, pic of my gland  fitted to one of my 'flat 4' power banks.

 

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aricooperdavis

Moderator
Ah I see, that's an excellent option. If you don't want to retrofit one of these onto a pack you already have then I have seen people create makeshift versions of these using a small spring and some heat shrink tubing:

ONETEsL_d.jpg
 
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