Emergency Light in Electric Cupboard - advice

[EFLImpudence]

Well, nothing lasts for ever.

A quick Google suggests a minimum of four years but might be considerably longer.

I think that is where they must maintain the three hour operation time,
but after that they may only last for, say, two hours for several more years - not satisfactory when being used for their intended purpose but won't hurt where you want to use them.

 

[FatherDougal]

Buy this or similar:
https://www.lampshoponline.com/led-emergency-maintained-bulkhead.html
Connect mains supply to it, and a switch between the L&SL terminals.
With mains power available, the switch turns the light on/off
When mains fails, the light switches on and is powered from the internal battery.

If I connect this into a socket what is the correct/best fuse size to use? I've been looking for the correct rating but I cannot locate the correct information.
As this powers via the battery and only charges the battery over a long period would a 3A or 5A fuse be sufficient to maintain the battery?

 

[Taylortwocities]

3

 

[ban-all-sheds]

As this powers via the battery and only charges the battery over a long period would a 3A or 5A fuse be sufficient to maintain the battery?

Err...

Why don't you know that the fuse on the 230V supply does not control the charging current?

And why don't you know how much current a 4-5W appliance draws?

 

[winston1]

The fuse is to protect the cable, not the appliance on the end of it, so it depends on what cable you are using.

 

[Risteard]

Fit a switch that will interrupt the power to the EM and the light will come on when you need to see in the cupboard.

The switch most certainly should not interrupt the emergency feed. That would be the test facility (i.e. keyswitch) which does that. A functional switch to operate the luminaire should only switch the switched feed to the luminaire and never the permanent feed.

 

[ban-all-sheds]

Risteard - this is a cupboard in somebody's house, not an emergency exit route in a public building. There's absolutely nothing wrong with a simple non-maintained emergency light and ordinary switch.

 

[Risteard]

Risteard - this is a cupboard in somebody's house, not an emergency exit route in a public building. There's absolutely nothing wrong with a simple non-maintained emergency light and ordinary switch.

If you want to ganch the battery...

 

[SimonH2]

Risteard - this is a cupboard in somebody's house, not an emergency exit route in a public building. There's absolutely nothing wrong with a simple non-maintained emergency light and ordinary switch.

So what do you think he suggested ? You really do not want a switch in the permanent feed to an emergency light (as stated, it will ruin the battery in double quick time), but if you mean having the switch in the switched feed to the light then I think you are in violent agreement

 

[EFLImpudence]

Why not just have a normal light which doesn't go off with household faults - and

if you want a light in a power cut, an emergency lamp - not much use in the cupboard - or a torch?

 

[Lectrician]

Most LED emergency bulkhead type lights are maintained these days. They can be used as non maintained. You have two live terminals, one via a test key switch, the other via a light switch if you wish, to illuminate it from the mains supply.

As I say, most on the shelf EM lights these days are maintained as standard, and are approx £8-£15 ex VAT.

 

[ban-all-sheds]

So what do you think he suggested ?

Sorry - my "normal switch" was a bit unclear. The point I was trying to make is that there's noting wrong with a basic non-maintained EM light with a non-keyswitch switch in the permanent live to it.

You really do not want a switch in the permanent feed to an emergency light (as stated, it will ruin the battery in double quick time),

Why will it?

 

[ban-all-sheds]

Most LED emergency bulkhead type lights are maintained these days. They can be used as non maintained. You have two live terminals, one via a test key switch, the other via a light switch if you wish, to illuminate it from the mains supply.

Sustained, surely?

• Maintained: On all the time, no functional switch in the supply.
• Non-maintained: Off when there is power, only illuminates when there's a power failure, no functional switch in the supply.
• Sustained: Automatically illuminates on power fail, can be switched on manually when there is power.

 

[Lectrician]

As I recall from teaching, and through everyday work, sustained contain TWO light sources, one battery fed, one mains fed. Maintained contains ONE light source fed from both battery OR mains.

A maintained fitting has two lives, which are usually linked with a disposable wire. If the wire was left in place the light would be on 24/7 and during power failure. As expected in cinemas, night clubs etc. The link can be removed and a switch used.

 

[333rocky333]

Sustained used to be popular, but not seen much nowadays, the idea was the lamp that was used for normal on/off purposes, was a seperate lamp to the lamp that lit on power failure, idea being that the emergency lamp should work even if the normal use lamp had worn out and not replaced .

Nowadays a Switched Maintained seems to be used for the same purpose, however its often found that the constant use of the lamp wears it out and if not replaced and goes unnoticed it then dont work in an emergency situation.

A majority do still have the link for the switching facility, but not all, nowadays, Maintained tend to be for situations where the BS standard requires 24 hour lit, whereas back in the day pre year 2000 it was acceptable to switch them off, even exit signs mainly to preserve lamp life, relying on staff to switch on when occupied.

To be fair in the OPs situation your proposal may do the batteries good, the amount of times the OP uses it , the power will probably be off less than the total time of a Duration test carried out on a commercially installed fitting.