Issues with dusk to dawn lights

[JohnD]

Modern LED lamps use so little electricity, and last so long, that trying to save a few pence with the "off" time is not worth the effort or expense.

 

[JohnD]

Interior switches, out of the weather and direct sunlight, last a long time,

24hr 7day Security Light Switch

but you will save more money by leaving it constantly On.

 

[ericmark]

Modern LED lamps use so little electricity, and last so long, that trying to save a few pence with the "off" time is not worth the effort or expense.

I would agree, however the Government says it must turn off in daylight hours.

6.60 Where installed in a new or existing dwelling, fixed external lighting should have both of the
following controls.
a. Automatic controls which switch luminaires off in response to daylight.
b. If luminous efficacy is 75 light source lumens per circuit-watt or less, automatic controls which
switch luminaires off after the area lit becomes unoccupied. If luminous efficacy is greater than
75 light source lumens per circuit-watt, manual control is acceptable.

So it seems we do need to have a control even if not economical to do so.

 

[JohnD]

They don't seem to mention solar lamps

 

[bernardgreen]

If you wanted on at dusk, off at a set time

Use a time switch to provide power ON at sometime during the day and OFF at the set time

24 Hour GP/Immersion Heater Timeswitch

Use the switched power to feed the lamp via the photo-cell's switch

 

[morqthana]

Any idea where I can get new photocell

Anywhere that sells Steinel products.

 

[morqthana]

Use a time switch to provide power ON at sometime during the day and OFF at the set time

24 Hour GP/Immersion Heater Timeswitch

Use the switched power to feed the lamp via the photo-cell's switch

Unless you have a photocell switch that turns on when power is applied.

 

[JohnD]

Any idea where I can get new photocell

https://www.screwfix.com/p/ced-indoor-outdoor-black-body-opal-head-photocell-standalone-sensor/980cg

 

[morqthana]

https://www.screwfix.com/p/ced-indoor-outdoor-black-body-opal-head-photocell-standalone-sensor/980cg

 

[FrodoOne]

Any idea where I can get new photocell

Anywhere that sells Steinel products.

Now, why did you specify Steinel.

They manufacture the "NightMatic 3000" (in several models)
which can switch off the lights at several "points" during the Night/Early Morning
and switch them on again just before Dawn - if required.


Unfortunately, you may not have access (in the UK) to this similar but more versatile device :-

https://www.cabac.com.au/amfile/file/download/file/97597/product/94003/

We utilize two of these.
One as a purely "Dusk to Dawn" sensor - for Garden/Driveway lights.
The other is for "Christmas Lights", which are turned On at Dusk and Off at around midnight.

(These Cabac devices tend NOT to fail.
The two mentioned have been working for 15 years.)

 

[SUNRAY]

Interior switches, out of the weather and direct sunlight, last a long time,

24hr 7day Security Light Switch

but you will save more money by leaving it constantly On.

Regarding economy one has to be so careful with this sort of device.
We fitted energy meters in an office block where they were wanting to save money.
I can't recall the exact details now but something like male and female toilets on each of 6 floors, each had a small lobby with a light then a light in the basin area and each cubicle/urinal area. All were CFLs so I guess ~7 or 11W
First person each morning would switch the lights on and the cleaners switched them off 10-12 hours later.
The energy saving expert electricians fitted 3 or 4 PIRs (dependant on male/female) in each facility.

As consumption went up, the electricians re-checked and gave the all clear, We were then asked to look at the meters. I happened to be still working on the project and spent much of a day in a riser in the lift lobby, from there it became quite obvious the lights were on for most of 9 hours of the day and beyond to a lesser extent so very minimal saving, however the PIRs were powered 24/365 including the relay at say1W plus it's relay at say 0.5W while the lights were on. Therefore adding 9x0.5 and 24x1 Wh per day or 10KWh each per year x~42 or 400KWh per year. OK not a huge amount but, as it turned out, a measurable increase.

I assumed I'd posted it before: https://www.diynot.com/diy/threads/bypassing-delay-switches.578891/page-2#post-5065701 post#21

 

[Harry Bloomfield]

As consumption went up, the electricians re-checked and gave the all clear, We were then asked to look at the meters. I happened to be still working on the project and spent much of a day in a riser in the lift lobby, from there it became quite obvious the lights were on for most of 9 hours of the day and beyond to a lesser extent so very minimal saving, however the PIRs were powered 24/365 including the relay at say1W plus it's relay at say 0.5W while the lights were on. Therefore adding 9x0.5 and 24x1 Wh per day or 10KWh each per year x~42 or 400KWh per year. OK not a huge amount but, as it turned out, a measurable increase.

I used to work, for a very large banking chain, with lots of offices. A specialist energy survey, flagged up the one per desk laser printers, left on, as a potential point for saving energy. Many thousands plug in time-clocks were issued, to plug the printers into, and limit the printers to only being on, during working hours.

It didn't take long, for the flaws to appear, when staff might decide they needed to start work a little early, work a little late, or there was a power interruption. In addition, the time-clocks, in operation, drew a similar 1/4w to the printers when the printers fell into sleep mode - so during the long hour of the day, when the printers were unused, they were paying for sleeping printer + timeclock. Then went the printers were switched on, on a morning, they would initialise, drawing lots of watts for several minutes, plus after a power cut, the whole office would be in chaos, unable to print, until an engineer had been called, to crawl under every desk, to sort the clocks out.

 

[morqthana]

Wasn't there a theory once that for commercial newbuilds, you'd save money by not paying for light switches and all the cabling thereof to be installed and just have all the lighting permanently on? I think the life-shortening powering on for fluorescents may also have been factored in.

 

[Harry Bloomfield]

Wasn't there a theory once that for commercial newbuilds, you'd save money by not paying for light switches and all the cabling thereof to be installed and just have all the lighting permanently on? I think the life-shortening powering on for fluorescents may also have been factored in.

I heard, for fluorescents - wear and tear, versus leaving them on, power wasted, if you were intending to return to the room in less than 90 minutes, then cheaper to leave them on for that 90 minutes. That was many years ago.

 

[SUNRAY]

I heard, for fluorescents - wear and tear, versus leaving them on, power wasted, if you were intending to return to the room in less than 90 minutes, then cheaper to leave them on for that 90 minutes. That was many years ago.

Yep, we worked on 60 minutes and even started installing 60 minute timers until the enormity of the task and cost was realised.