Low energy light bulbs in outside sensor lights

MrsE_2

Flame me now but I hate low energy bulbs, they are so ugly.

I got 2 free from Southern Electric.

But they are a baynet fitting & I was thinking of using them in my outside front lantern (light), but it takes a screw fitting.


Anyway the lantern is on a security hi-lo with light sensor.

As darkness falls it comes on at 60 watts, if someone approaches the drive & the sensor makes it brighten up to 100 watt, otherwise it just stays at 60 watts until dawn.

Saw some in Morrisons (screw fitting, 11 watts susposed to be as good as 60 watts) & bought them for 49p for 2!!!!!!!


But it doesn't do the hi-lo thing. Just the one brightness

Anyone used these bulbs in sensor lights?

I suspose its cheaper to have it on full all the time at 11 watts anyway, that to run the hi-lo at 60 & 100.

TimBuckTeeth

Compact fluorescent lamps can be used in some fittings with PIR sensors or light sensors, but it depends on the type, it will state in the instructions.
It is a good idea to use a compact fluorescent lamp in a dusk to dawn lantern as it is on for several hours a day so saves more energy and lasts longer, compared to a toilet room (for example) where the benefit is marginal.

Compact fluorescent lamps cannot be used with dimmer controls, which is essentially what your hi-lo lantern does. It may damage the circuit in the lantern or the lamp.
So you can either swap back to a conventional bulb, leave it and hope for the best or change the lantern to one that can be used with fluorescent lamps.

MrsE_2

Thank you.

Amazing how you can get info on anything answered on this site :-)

economiser

MrsE wrote: »

Saw some in Morrisons (screw fitting, 11 watts susposed to be as good as 60 watts)

This is a common claim but it's nearer to 50W. Also often claimed that 15W = 100W but it's nearer 75W.

theloft

A lot of PIR detector lamps state on the box - Unsuitable for use with low energy bulbs - I tried to use one in mine and it didn't work.

andrew-b

Yes the PIR (and dusk sensor if fitted) constantly draws a small current. As i understand it, normal tungsten light bulbs will let that small current pass without emitting light to complete the circuit but energy saving normally won't.

Andy

TimBuckTeeth

andrew-b wrote: »

Yes the PIR (and dusk sensor if fitted) constantly draws a small current. As i understand it, normal tungsten light bulbs will let that small current pass without emitting light to complete the circuit but energy saving normally won't.

Andy

That is true for timer and PIR units that fit in place of a lightswitch as a neutral connection is not available.
A normal light bulb acts like a resistor, a small current flow provides around 5 Volts to power the control circuit without illuminating. A compact fluorescent lamp will not conduct with a low voltage/current so the control circuit may not operate reliably and the lamp may flicker as the internal capacitor charges up.

For an outside light with a PIR sensor a neutral connection is available, current is not passed through the bulb to power the control circuit.
Whether it is suitable for use with compact fluorescent lamps depends on how the power to the lamp is switched. If a relay is used on the circuit board then it should be fine for use with fluorescent, if it is switched electronically using a triac then it may be damaged if a compact fluorescent lamp is used as relatively high currents are drawn briefly during the mains ac cycle.