Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?


http://www.screwfix.com/prods/39148/...ight-Photocell

http://www.screwfix.com/prods/35156/...ell-Floodlight

Thanks.

Well the reviews on the latter say it isn't much good.

Decide how much lighting you want.
- SON re industrial sodium yellow light
- Fluorescent re conventional warm-cool white light

Decide how you want to control them.
- Single industrial photocell on wall switching the lot
- Individual photocell integrated into each light unit

Lights with integrated photocell provide better reliability at higher
cost, industrial photocell (box on a wall) are however quite reliable.


Ebay had some Coughtrie cbc IP65 photocell fluorescent lights for
£9-14, diecast aluminium opal diffuser, normally £45 normally as
proper industrial lighting gear. Nothing like them on there now
unfortunately as the price was excellent. Do not use the ASD bulkhead
photocell, they used to fail quite often.

Going for "real" IPx4 or IPx5 is a good idea re fit-n-forget. Go to
any electrical wholesalers and see what they have.

On Sun, 24 May 2009 18:26:05 +0100 someone who may be "Johnny
OneSpanner" wrote this:-

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?

Depending on the particular sodium lamp, sodium lamps are likely to
have a lower life-cycle cost due to the lower running costs for a
given lighting level. OTOH it will be more difficult to achieve an
even level of illumination with sodium lamps, as fewer will be
needed for a given level of illumination. However, fewer lamps may
mean less wiring depending on the particular circumstances.

I would go for sodium lamps, there is a selection at
http://www.tlc-direct.co.uk/Main_Index/Lighting_External_Index/Lighting_Floodlight_Index/Commercial_Lighting/index.html

Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?

They have advantages and disadvantages, the main disadvantage being
that if it fails there will be no light at all, or light all day. If
you go for one drive a relay/contactor from it and use that to
switch the lamps.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article ,
"Johnny OneSpanner" writes:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?

Yes, but they're less efficient, both the raw lamp itself, and because
it's not possible to design luminare optics for such a large light source
as efficiently.

Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?

Yes, but you should go and try an electrical wholesaler, who
will have a better selection than ScrewFix.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Johnny OneSpanner wrote:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?


http://www.screwfix.com/prods/39148/...ight-Photocell

http://www.screwfix.com/prods/35156/...ell-Floodlight

Thanks.

The various types of sodium light all have way better energy
efficiency, and thus lower run costs, than CFL
http://www.wiki.diyfaq.org.uk/index....harge_Lighting
If you dont mind spending extra dough for white light, cfl or linear
fl are an option.


NT

In article ,
"js.b1" writes:
Well the reviews on the latter say it isn't much good.
Decide how much lighting you want.
- SON re industrial sodium yellow light

SON (high pressure sodium) are a peachy, very warm white, but
don't have good colour rendering.

SOX (low pressure sodium) are the really yellow ones with no
colour rendering, but I doubt you'll find any (new) SOX
fittings, as the lamps are being phased out. (Somewhat ironic
given they're still the most efficient widespread light source
available.) Councils should have programmes to swap these out,
and you might be able to pickup some cheap, but make sure you
also get a lifetime stock of lamps, as they will become
unavailable (and they're expensive - I think there's only one
manufacturing facility for them still left).

- Fluorescent re conventional warm-cool white light
Decide how you want to control them.
- Single industrial photocell on wall switching the lot
- Individual photocell integrated into each light unit
Lights with integrated photocell provide better reliability at higher
cost, industrial photocell (box on a wall) are however quite reliable.
Ebay had some Coughtrie cbc IP65 photocell fluorescent lights for
£9-14, diecast aluminium opal diffuser, normally £45 normally as
proper industrial lighting gear. Nothing like them on there now
unfortunately as the price was excellent. Do not use the ASD bulkhead
photocell, they used to fail quite often.
Going for "real" IPx4 or IPx5 is a good idea re fit-n-forget. Go to
any electrical wholesalers and see what they have.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Johnny OneSpanner wrote:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?


http://www.screwfix.com/prods/39148/...ight-Photocell

http://www.screwfix.com/prods/35156/...ell-Floodlight

Thanks.



Can't add much to what others have said (but 70W SON would be my first
choice).

However, I recently brought this stand-alone dusk-dawn sensor from
Toolstation and it's OK (as in good value for money - but not industrial
quality):

http://preview.tinyurl.com/r4q6en

It has a 10A relay and a 6.3A HRC 20mm fuse inside and is rated by the
manufacturer at 1.3kW resistive load.

De-rating for 70W self-igniting discharge lamps (e.g. Osram 70W SONI-E),
it should comfortably switch up to 8 Luminaires.

Johnny OneSpanner wrote:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?


http://www.screwfix.com/prods/39148/...al-Floodlights

/Trac-Trac-Pro-SON-70W-Asymmetric-Commercial-Floodlight-Photocell

http://www.screwfix.com/prods/35156/...-Floodlighting

-Light-42W-Black-Photocell-Floodlight

Thanks.

If they've got motion activated halogens allready where's the advantage
in having other

lights that are ON all the time it's dark,is there something wrong
with the MA lamps or

sensors? are they positioned too low down so they can be interfered
with? or is it that

the ON time is too short.
Would they be better off investing in a camera,siren or something else
in addition to the existing lights, or am I missing something here?

Don

"Donwill" ""diddle\"@popple,dot" wrote in message
...
Johnny OneSpanner wrote:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen
lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights
also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the
ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?



http://www.screwfix.com/prods/39148/...al-Floodlights

/Trac-Trac-Pro-SON-70W-Asymmetric-Commercial-Floodlight-Photocell


http://www.screwfix.com/prods/35156/...-Floodlighting

-Light-42W-Black-Photocell-Floodlight

Thanks.

If they've got motion activated halogens allready where's the advantage
in having other

lights that are ON all the time it's dark,is there something wrong
with the MA lamps or

sensors? are they positioned too low down so they can be interfered
with? or is it that

the ON time is too short.
Would they be better off investing in a camera,siren or something else
in addition to the existing lights, or am I missing something here?

Don


Thanks for all the comments.
For wiring reasons, there will probably be only one light, so a 70W Sodium
lamp looks like a good solution.

I'm a little surprised that the police recommend dusk-til-dawn low level
lighting, but I supose the reasoning goes something like this:
- It provides a visible deterrent for any burglars scouting the area,
hopefully they will be discouraged before they ever get within range of the
halogen lights' PIRs.
- It provides reassurance to anyone looking out of a window (or through the
camera, which is also installed), that no-one is sneaking around, having
somehow dodged the PIRs. Because of the layout of the property, it's
difficult to provide 100% reliable PIR coverage without getting lots of
nuisance triggers from cats, foxes, sheep, etc.

Johnny OneSpanner wrote:
"Donwill" ""diddle\"@popple,dot" wrote in message
...
Johnny OneSpanner wrote:
Hello -

In response to local burglaries, some relatives have been advised by the
police to install a dusk-to-dawn low-level floodlight in their small (15
metres across) farmyard., which already has motion-activated halogen
lamps.

The police recommend a sodium lamp, but are the CFL-based floodlights
also
suitable?
Sodium lamps with dusk-til-dawn sensors seem to be quite thin on the
ground,
should I use a separate sensor?
Can anyone comment on whether these might be suitable?



http://www.screwfix.com/prods/39148/...al-Floodlights

/Trac-Trac-Pro-SON-70W-Asymmetric-Commercial-Floodlight-Photocell


http://www.screwfix.com/prods/35156/...-Floodlighting

-Light-42W-Black-Photocell-Floodlight

Thanks.

If they've got motion activated halogens allready where's the advantage
in having other

lights that are ON all the time it's dark,is there something wrong
with the MA lamps or

sensors? are they positioned too low down so they can be interfered
with? or is it that

the ON time is too short.
Would they be better off investing in a camera,siren or something else
in addition to the existing lights, or am I missing something here?

Don


Thanks for all the comments.
For wiring reasons, there will probably be only one light, so a 70W Sodium
lamp looks like a good solution.

I'm a little surprised that the police recommend dusk-til-dawn low level
lighting, but I supose the reasoning goes something like this:
- It provides a visible deterrent for any burglars scouting the area,
hopefully they will be discouraged before they ever get within range of the
halogen lights' PIRs.
- It provides reassurance to anyone looking out of a window (or through the
camera, which is also installed), that no-one is sneaking around, having
somehow dodged the PIRs. Because of the layout of the property, it's
difficult to provide 100% reliable PIR coverage without getting lots of
nuisance triggers from cats, foxes, sheep, etc.

70w should be about the right power for that size too


NT

In article ,
writes:
70w should be about the right power for that size too

You need to mount it high up too.

Ideally, you should get the photometric data from the light's
datasheet, and work out the correct mounting hight to cover
the area. In practice, you might find this data doesn't exist
unless it's a good make, and that the mounting height it
gives you is higher than you can manage.

If you have neighbours, check that either the light doesn't
spill onto their property, or that they don't mind. If there's
a road nearby, check the light doesn't cause dazzle to road
users. Always adjust the light so the beam cutoff is below
horizontal to minimise light polution.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Andrew Gabriel wrote:

If you have neighbours, check that either the light doesn't
spill onto their property, or that they don't mind. If there's
a road nearby, check the light doesn't cause dazzle to road
users. Always adjust the light so the beam cutoff is below
horizontal to minimise light polution.


Yes! I do a bit of amateur astronomy and security lights are one of the
banes of my life. Most of them spill light upwards which is both a waste
for the owner and a nuisance to me.

Another Dave.

Johnny OneSpanner wrote:

Thanks for all the comments.
For wiring reasons, there will probably be only one light, so a 70W Sodium
lamp looks like a good solution.

Another option might be a 70 watt HQI metal halide[*] lamp. Much better
colour rendering than SON and pretty good lumens/watt efficiency,
although not quite as good as sodium. Googling "hqi floodlight
photocell" finds a few suitable luminaires.

[*] Don't confuse "metal halide" with "tungsten halogen" - they're
totally different things.

--
Andy

Donwill" ""diddle\"@popple,dot wrote:

Would they be better off investing in a camera,siren or something
else in addition to the existing lights, or am I missing something
here?

My recent experience of cameras suggest that in most cases they'll be a
waste of time. The cheap ones tend to pick up bugger all, and end up
massively overexposed when the halogen floodlamps come one. I'm sure the
expensive ones are far far better, but you're then spending a hell of a lot
of money to get good coverage and to record everything.

OTOH once you've had stuff nicked and know which way they're coming in and
out, you have a hope of getting a camera and recorder in the right place
with the right lighting...

On 25 May, 16:27, Another Dave wrote:
Andrew Gabriel wrote:

If you have neighbours, check that either the light doesn't
spill onto their property, or that they don't mind. If there's
a road nearby, check the light doesn't cause dazzle to road
users. Always adjust the light so the beam cutoff is below
horizontal to minimise light polution.

Yes! I do a bit of amateur astronomy and security lights are one of the
banes of my life. Most of them spill light upwards which is both a waste
for the owner and a nuisance to me.

Another Dave.

SOX is near single line output, can use a dichroic filter to notch it
out.

Light tresspass is a real problem, now entering legislation in
Scotland, mounting a sharp cutoff flood high, pointing down should
keep it to a minimum,
Ofetn see them mounted far too low with resultant spill everywhere, in
the contryside its not just people who need darkness at night.
Remember light not on target is money going to waste.

Adan