How To Build A Contactor For 2-4 600watt Hps

[bren]

i 've looked at the pinned how to build a contacter

but what would i need for 1 that can operated 4 x 600 watt lights

please help

[Themadhippy]

but what would i need for 1 that can operated 4 x 600 watt lights

a bigger relay,actually a contactor in this case,something rated for a 20A inductive load wil do the job nicley (around £60 from your local electrical wholsaler)

[bren]

a bigger relay,actually a contactor in this case,something rated for a 20A inductive load wil do the job nicley (around £60 from your local electrical wholsaler)

what it will cost £60 to buy the shit to build one or do you just buy a complete unit for £60

[Redseal]

what it will cost £60 to buy the shit to build one or do you just buy a complete unit for £60

Maplin sell a 30A relay for a fiver.. the whole thing could be built for about £15 or so.

[bren]

Maplin sell a 30A relay for a fiver.. the whole thing could be built for about £15 or so.

in the pinned thered diagram they've used a round based relay does this matter cause i can only find a Power Relay 30A single pole double throw 240 v ac will this be ok cat no. N24AW

will this be all i need apart from wire, plugs and case

thanks

[Redseal]

in the pinned thered diagram they've used a round based relay does this matter cause i can only find a Power Relay 30A single pole double throw 240 v ac will this be ok cat no. N24AW

will this be all i need apart from wire, plugs and case

thanks

Should be ok.. there seems to be a lot of missing pictures in that thread now so not sure how it's wired up. Any cable and terminal blocks used will need to be able to handle the current aswell.

[bren]

Should be ok.. there seems to be a lot of missing pictures in that thread now so not sure how it's wired up. Any cable and terminal blocks used will need to be able to handle the current aswell.

yer that's sound mate i'll ask em in the shop as well just to make sure

[Themadhippy]

i very much dout the maplins relay will last very long switching 2400 watts (switching current of around 18A inducticve) of hps lighting,much safer (and cheaper in the long run) to vist your local electrical wholsalers and ask em for a suitable contactor for the job

[grobag]

I to favour contactors over relays for high loads.

[bren]

i very much dout the maplins relay will last very long switching 2400 watts (switching current of around 18A inducticve) of hps lighting,much safer (and cheaper in the long run) to vist your local electrical wholsalers and ask em for a suitable contactor for the job

what so your saying just don't bother with 30a power relay and 18a of light will blow it sooner rather than later

[Themadhippy]

yep.it maybe rated for 30A,but thats for a purley resitive load.just had a quick google and heres the specs for an equivalent relay

Resistive Load 30A at 250VAC, 20A at 28VDC

Max Switching Power resistive 7500VA reactive 560VA

Rated Voltage 5 to 110VDC 5 to 240VAC

Power Consumption 900mW

Mechanical Endurance 10,000,000 operations minimum

Electrical Endurance 100,000 operations minimum

Operating temperature -55° to 105°

looking at those specs youd be hard pushed to switch 1,let alone 4 hps lamps

Edited December 14, 2005 by Themadhippy

[bren]

yep.it maybe rated for 30A,but thats for a purley resitive load.just had a quick google and heres the specs for an equivalent relay

looking at those specs youd be hard pushed to switch 1,let alone 4 hps lamps

right the relay youy quoted would be equivalent you say

then you go on to say it won't switch 1 no alone 4 so what do i need excacly for

2 x 600watt hps and 4 x 600 watts hps

sorry to keep asking

[cf]

you need a contactor not a relay

contactors look like this

[Themadhippy]

sorry to keep asking

bloody young wiper snappers coming on here and pesting us with there questions,anyone would think its wot the boards are ment for

4 x 600 watts =2400 watts,from watts=volts times amps you'd assume 10 amps ,however were talking hps lighting here so we have to take a little thing called power factor into account, 0.8 is the accepted questimate without manufacters figures so the formuler becomes volts x amps x power factor or in this case 2400/20 x 0.8 = 12.5 amps, this is the current the relay will have to switch. so its a 12.5A relay we'd need? well yes if the switch is rated for hps lighting, if your switch dosnt have an inductive rating then you need to multiply it by 1.8.so our switch may need to handle 22.5Amps, however the relay maplins sells is olny rated for an inductive load of 2.3 amps,so its a little bit on the small side.

so what you need is a relay or contactor that can handle an inductive load of 12.5A, something like this contactor will do the job nicley,according to the manufacters it will handle upto 15A of lighting,not the 13A the other site claims. 2 x 600 watters needs a 6.25A contactor,if your switching all 6 off the one contactor then its 18.75A or something like this contactor

one final question how do you intend to power your lights as a 13A socket wont like it,your looking at a dedicated supply from your fuse board,even 2 x 600watt lamps may blow a 13A fuse if they both switch on together

[bren]

bloody young wiper snappers coming on here and pesting us with there questions,anyone would think its wot the boards are ment for

4 x 600 watts =2400 watts,from watts=volts times amps you'd assume 10 amps ,however were talking hps lighting here so we have to take a little thing called power factor into account, 0.8 is the accepted questimate without manufacters figures so the formuler becomes volts x amps x power factor or in this case 2400/20 x 0.8 = 12.5 amps, this is the current the relay will have to switch. so its a 12.5A relay we'd need? well yes if the switch is rated for hps lighting, if your switch dosnt have an inductive rating then you need to multiply it by 1.8.so our switch may need to handle 22.5Amps, however the relay maplins sells is olny rated for an inductive load of 2.3 amps,so its a little bit on the small side.

so what you need is a relay or contactor that can handle an inductive load of 12.5A, something like this contactor will do the job nicley,according to the manufacters it will handle upto 15A of lighting,not the 13A the other site claims. 2 x 600 watters needs a 6.25A contactor,if your switching all 6 off the one contactor then its 18.75A or something like this contactor

one final question how do you intend to power your lights as a 13A socket wont like it,your looking at a dedicated supply from your fuse board,even 2 x 600watt lamps may blow a 13A fuse if they both switch on together

right i'm just gonna get 2 600 hps for now well after xmas at least my grows in a garage thats got a fuse box in it which is the wired to the fuse box in the house with the trip awitch i'll find out whats whats with the fuses and ratings and stuff, i am in the UK by the way if that makes any difference

cause if you look on uk420 grow shop they have a relay / contactor section with info and say you can have 4 x 1000 watt lights with a 20amp relay contactor, so go on this a 10amp would work with 2 x 600watts but is this not the inductive load