external lighting

[sparkyb2]

hello lads , my querie is i have 10 external 500w sodium lights to fit outside a garage building rougley 50 m x 30 m long and i mainly work on house rewires so any help would be gratefully accepted in helping me with materials i need to order as the owner tells me he would like them on a time clock for night time operation and would it be better to use a 3 phase contactor as well to spread out the lights onto 2 circuits of 3 and 1 circuit of 2.
Much appreciate any input please.

 

[Spoon]

Rather than putting the lights on a timer for night time wouldn't it be better fitting a daylight sensor? Saves messing about with the timer for the different times of year.

 

[sparkyb2]

Iwould rather include a pir to bring the contactor in when it starts to get dark and lighter in the mornings and would i need a 3 phase contactor as well if this option used for starting the lights up rather than a switch and any idea of a contactor in an enclosure .

 

[Guest111]

It's not a pir you want,it's a photocell.you'd want to go through the cell then a timer so you could have the lights set from say 4 'till midnight but in summer the lights would only come on when it went dark but still go off at midnight.

 

[sparkyb2]

right a pir which is 240 v , a 240 v time clock and a 3phase 415 v contactor would work and operate these lights through our different seasons and changes in the seasons

 

[Spoon]

Is there any need for a timer phil if he is using a 'dusk-till-dawn sensor'? The lights will just come on when it gets dark enough.

 

[sparkyb2]

sorry meant photocell

 

[Guest111]

NO! forget the pir,that will only come on when it detects movement,it's a photocell that you need,wire from this to a timeclock then to the 240v coil on a 3 pole contactor,the three poles are then used to feed the 3 light circuits.where are you btw?

 

[Guest111]

take a live and neutral to photocell,then live from LO on photocell to common on timeclock,then from NO on clock to A1 on contactor,then A2 on contactor to neutral.When it goes dark photocell turns on feeding power to clock,now even though clock may be set to come on at 4 pm if it doesn't go dark 'til 6 the photocell won't switch.This saves altering settings for summer and winter.

 

[sparkyb2]

Cheers Phil D this will get these lights working off a photo cell and might do away with the time clock and have lights working off the photo cell.

 

[Spoon]

Personally I would not use a timer if I was using a photo cell. I don't see the need for both.

 

[Guest111]

Is there any need for a timer phil if he is using a 'dusk-till-dawn sensor'? The lights will just come on when it gets dark enough.

The timer is good for turning them off later on,if it's say a car sales garage they may not want the forcourt lit when there's no passing trade,so having them going off at say 2 AM, this would also save quite a few quid on the running costs,if they don't want this then just omit the timer.

 

[Andy78]

Cheers Phil D this will get these lights working off a photo cell and might do away with the time clock and have lights working off the photo cell.

I would incorporate a timeclock too unless your customer wants 5kW of lighting burning away all night.

 

[Spoon]

The OP did say that the customer "would like them on a time clock for night time operation"
I'm taking that as all night. If not then of course a timer is necessary.

 

[Guest111]

It's one of them isn't it? The customer would like,until he gets his electric bill.lol