Low energy lamps in security lights

[Jason]

Hi

I've been looking to replace as many of the bulbs in my house as possible with low energy ones, and wondered if anyone could help with some advice on obtaining the following:

- Replacements for 60w ES bulbs, which are switched by PIRs. All of the lamps I've seen state they're not suitable for dusk/dawn or PIR switches. I assume this is due to a heavy surge surrent when they're first switched on. Does anyone know where I can get some that ARE suitable for use with PIR switches?

- The highest power candle bulb replacements I've seen are 7w (Screwfix and Toolstation). They're apparently equivalent to 40w. Does anyone know where I can get 11w ones, or are the 7w ones alright?

Finally, are there effective (and reasonably priced) R50 SES replacements available, or am I looking at replacing the kitchen light fittings?

Thanks in advance.

Cheers

Jason

[Andrew Gabriel]

The reason is that many dusk/dawn and PIR switches reply on powering themselves through the lamp filament, and this doesn't generally work if you use a compact fluorescent. Dusk/dawn and PIR switches which use a relay will work fine -- can you hear a relay click when your lights go on and off?

Secondly, compact fluorescents are unsuitable for frequent and short-term switching associated with PIRs. They can take a few minutes to warm up to full light output, particularly in the cold. Frequent switching will have a detrimental impact on their life.

My rule is to multiply the power by 4 times to get the equivalent filament lamp, so I don't believe 7W will be equivalent to a 40W lamp. YMMV...

For outdoor lamps, particularly in winter, I would suggest using the type with an additional outer glass bulb (which probably is the case with your candle lamps) rather than those with exposed tubes, which can struggle to get up to temperature.

R50 compact fluorescents exist. I don't have personal experience on how effective they are. The difficulty in folding the tube into the available space and getting all of the tube exposed to the front means, I suspect, that they would not do as well as my 4-times rule, which means you are going to struggle to get the same lighting level from them.

[Harry Bloomfield]

Jason wrote on 23/04/2006 :

The problem is not the switch on surge or running current, but the fact that some PIR units work without a live going to them - depending upon the the low resistance of the lamp to pass enough current to supply the PIR unit. If there are several lamps on one PIR, then make one a normal lamp and it should work fine. Anther way is to add a resistor across the lamp terminals to pass enough current.

Having said that, low energy lamps are best not used in places where they can expect frequent switching to take place. A secondary problem is that their light output is poor on initial switch on until they have warmed up. Outdoors this could take some time, especially so in winter.

[Guy King]

The message from "Jason" contains these words:

I've used 'em in PIR lights without trouble for years.

[Mary Fisher]

We don't have a PIR security light because the frequent switching on and off is irritating. Well, more than irritating.

But we use a low energy lamp in a holder which is sensitised by low and high light conditions. It comes on at dusk and goes off at sunrise, all year round.

This might not be what you want but for us it's ideal.

Mary

[David Hansen]

On Sun, 23 Apr 2006 19:06:05 +0100 someone who may be "Jason" wrote this:-

For such things instant startup is desirable. Dusk to dawn lights are an alternative.

Alright for what? Answers depend on your circumstances and opinions.

Yes they are available. For example B&Q sell them for about £10. I think this reasonable, others may not.

[chris French]

In message , Andrew Gabriel writes

Yeah, I fitted a 'dusk/dawn' sensor that would work with CFL, but for PIR operated lights which are usually only on for a few minutes it doesn't seem worth worrying about anyway.

Yeah I use the 4x rule - even at the normal claimed 5x it's only be 35 W

Re availability, look for specialist sellers, they have wider variety than more generalist sellers. A web search for 'light bulbs' etc. will turn up a number of retailers.

I've used

In the last year.

The latter list 11W CFL candle

[Guy King]

The message from "Mary Fisher" contains these words:

You can adjust/mask the sensor so it only goes off when you want it to.

[Mary Fisher]

Loses the point, really!

[Guy King]

The message from "Mary Fisher" contains these words:

No it doesn't. We've a PIR by the front door, but unmasked it reacts to people walking along the footpath outside. Masked it only lights as you walk through the gate.

[Pete C]

Depends on the size of room and number in the fitting. Philips do a 9w candle eg:

The problem they might have is that they stick out too much, so it's worth measuring the existing bulb and fitting to see how much room there is.

These might be OK in most fittings:

I've had good results with normal round shape 12w Philips Softone bulbs in R80 spots, they stick out a little but aren't too bad.

The other thing to watch out for is the colour temperature and CRI (colour rendering index) Colour temperature is basically how cool or warm the light is, and CRI how evenly balanced the light is in colour terms. A Google search will get you a much better explanation ~:)

If you get bulbs from Philips or Osram they should give pretty good CRI and their websites should give details, but some bulbs esp. unbranded or 'own brand' ones may not be that good. This may not matter /that/ much in a kitchen but will in a living room or bedroom.

For long term task lighting like over a desk or most used kitchen worktop a couple of halogens might still be worth having.

cheers, Pete.

[Frank Erskine]

On Mon, 24 Apr 2006 11:21:57 +0100, Guy King had this to say:

There's a street nearby where if you walk along the footway in the evening, PIR "controlled" lamps on both sides of the road at two particular houses activate almost simultaneously, even though the gardens are reasonably long.

[Mary Fisher]

Gosh, how useful!

We have a dusk todawn light in the carport so that we can see in the dark if we need to go out and so that visitors can also see. I'd rather not have it at all, there's enough light from others ources, but Mr Gadget Man (Spouse) wanted to use a rather nice light bracket he found in the depths of the garage.

It makes me smile when he complains about people using torches when there's no street lighting, saying that it spoils their night vision. He's right, it does, but he can't relate that to our 'security' light.

But he's a man.

What security does it give by the way?

Mary

[Guy King]

The message from "Mary Fisher" contains these words:

What, ours? None, it's so you can see to put the key in the lock.

[Mary Fisher]

You can get these little torches which attatch to your key ring ... or usethe one in your mobile ... or simply feel for the keyhole.

Or call them keyhole lights, not security lights. And they don't need to be pir or filtered.

Mary

[Guy King]

The message from "Mary Fisher" contains these words:

Ah - the wife can't really manage that. She needs two hands to get the door open.

[Helen Deborah Vecht]

"Mary Fisher" typed

False sense thereof, methinks...

[David Hansen]

On Mon, 24 Apr 2006 12:18:59 +0100 someone who may be "Mary Fisher" wrote this:-

Very useful in one of the houses in the family. The light comes on as a human reaches for the gate on the drive. It is not set off by the neighbours or people on the path. Now all we have to do is stop a cat setting it off.

Nothing wrong with being of the male persuasion.

Low level lighting does deter some people, who would rather be in the dark. However, it does not deter all of them.

[Mary Fisher]

Quite.

Nothing at all. But many of them do seem to have inconsistent thinking - not you IME.

No. And it's rarely dark in cities. Our drive certainly isn't even without the light :-(

Our house is one of the few in this street which hasn't a burglar alarm, many prominently displayed.

Our house is one of the few in this street which hasn't been burgled.

Those facts aren't necessarily related but those without alarms never cause nuisance by 'false' alarm soundings. There are advantages and disadvantages to any device.

Mary

[Owain]

That's good, coming from a woman!

Ditto

That, Mary, is because your house is one of the few in the street - probably in the land - where the bin lorry doesn't collect, it delivers. Empty jam-jars? Scrap iron? Anything that can be unpicked/unravelled/reused/recycled? The Fishers will take it, if they haven't already got it, which by now they probably have.

(In the nicest possible way, of course.)

Owain