green dreemer Posted March 3, 2009 Share Posted March 3, 2009 the reason you need a contactor has nothing to do with the wattage of yyour light its the fact that starting a hid light takes nearly 5000 volts to start it and its this surge that destroys timers not the wattage of the light so no a 1.5 kw imersion heater timer wont work Link to comment Share on other sites More sharing options...
green dreemer Posted March 3, 2009 Share Posted March 3, 2009 Hey GuysWas reading into the whole timer thing and found this thread very interesting and it certainly made me question if I need one of these contactor things. So I done my research and came across this. Would you mind having a look and seeing if this is sufficient enough for me? I have one 400w light in a wardrobe. Heres the link, hope it works Envirolite Timer/Contactor £14.95 Click HERE the blurb says it should be ok but ring a grow shop to be on safe side Link to comment Share on other sites More sharing options...
green dreemer Posted March 3, 2009 Share Posted March 3, 2009 hi i been reading this thread and im proper paranoid about fire so i wanna do my grow as safe as i can i have a 250 hps and i aint got a relay yet but in 2 minds to get one not because of the cash as mine and my familys lifes are priceless but my problems is where i want to grow there is only one mains plug socket. i wanna know if it is safe or possible to run a four way adapter (surge protected) from that one socket then plug up the relay to that as they alll seem to be 2 plug relays and then mabe run fan on that extenstion as welll does anyone actully do this or is it remotely safe thanks in advance ragingbull totally safe do it all the time as i to have a shortage of plugs and my grow uses 9 pluged pieces of equiptment Link to comment Share on other sites More sharing options...
green dreemer Posted March 3, 2009 Share Posted March 3, 2009 HiWould I need a contactor/relay for my growroom? I'm planning on using 2 x 200W enviros? Sorry if it's a stupid question but I have no idea when it comes to electrics. Also, could someone explain to me what an RCD is and if I need one. Cheers no contacor required on enviros just hid's Link to comment Share on other sites More sharing options...
green dreemer Posted March 3, 2009 Share Posted March 3, 2009 i dont get the argueing about this subject ALL HID LIGHTS NEED A CONTACTOR if you want to use a timer i bured out a timer on a 100 watt halide it took a while but it still happend!!!!!! Link to comment Share on other sites More sharing options...
Sensi Addict Posted March 7, 2009 Share Posted March 7, 2009 I use an old "pin" timer ripped off a central heating boiler , its done well so far switching on upto 3x 250W lights for a couple of crops and still going strong. cost me £3.50 from ebay . Link to comment Share on other sites More sharing options...
maccer Posted March 10, 2009 Share Posted March 10, 2009 well said fido. some people come out with all sorts of theorys about electricity,wipe your mouths you talk sh*t. if the enviro timer dreamer is on about says its ok for 1 600w hid then it must be so(trading standards and all that) any more either watts or lights get a contactor/relay. Link to comment Share on other sites More sharing options...
scraglor Posted March 18, 2009 Share Posted March 18, 2009 (edited) The ballast provides the start-up voltage, not the mains. It's the current, not the voltage, that kills timers, the voltage through the timer is constant at 240V. no, the ballast produces a voltage spike to strike the arc across the tube. there is a brief current transient caused by the capacitor, taht can be up to around 30 times running current, this lasts for half the ac cycle, (1/100th of a second) this is often enough to weld timer/relay contacts shut. the inducatnce of the ballast causes a voltage surge when the timer is switched off. the magnetic field in the core of the ballast collapses and creates a voltage pulse, similar to how a car ignition coil works. the igniters used for hps lamps creates a 5kv pulse by means of a small electronic tank circuit. the current of course does the damage, but an arc can't occur without a high voltage, so the high voltage pulse causes an arc, allowing current to flow = fucked timer. those fuse requirements are the absolute minimum allowed by bs7671. try running 30A thorugh a 13A fuse and see how long it lasts! a 400w will pull an rms current at start up no higher than about 9-10amps, (negating the transient PEAK current drawn by the capacitor, this is a transient current and not the starting current of the ballast, also this depends on line inductance and various other conditions upon switching) e2a: although, i was wrong in that quote, should have said for protection against overload, not shock, although plug top fuses are of course there for both reasons, depending on application Edited March 18, 2009 by scraglor Link to comment Share on other sites More sharing options...
Guest Logik Posted March 30, 2009 Share Posted March 30, 2009 (edited) All I know is that relay and contactors are different in the smallest way but makes the biggest difference. ( reading from alot of guides and pros) use a contactor, better safe than sorry. If you aint prepared to make sacrifices in the pocket, dont grow, because you put people around you in danger not just yourself Edited March 30, 2009 by Logik Link to comment Share on other sites More sharing options...
Snatcher420 Posted April 9, 2009 Share Posted April 9, 2009 All I know is that relay and contactors are different in the smallest way but makes the biggest difference. ( reading from alot of guides and pros)use a contactor, better safe than sorry. If you aint prepared to make sacrifices in the pocket, dont grow, because you put people around you in danger not just yourself I just use one of these... Coralife Digital Power Center Wave Maker/Light Timer. 8-Outlet Timer/Power Strip 4 timer-controlled outlets 4 constant-power outlets 24 hour digital timer 15 minute setting intervals Great for switching water pumps to create tidal- flow currents Alternate day-night cycle timer Master on/off control switch 3-foot heavy-duty power cord Sliding outlet safety covers 3-prong grounded plug and outlets 15 amp 120 volt (1875 watts max.) circuit breaker UL listed . Works like a charm..Has a 600 hps,250mh,bath vent fan,oscillating fan,2 cage fans,and one blower fan hooked up to it. Link to comment Share on other sites More sharing options...
Joint hogger Posted April 9, 2009 Share Posted April 9, 2009 this is my contactor, got it of fleabay a few years ago & havent used it yet, think it cost about £20. im not sure about how to use it properly, does one of the plugs plug into a timer, which then plugs into the socket & i plug the ballast into the contactor, is that right or do i plug the two contactors plugs into a socket & put the timer into the contactor ? cheers Link to comment Share on other sites More sharing options...
Sugarwoods Posted May 7, 2009 Share Posted May 7, 2009 Really useful thread. I had to buy a contactor - got this one from Green's. I only have a 125w HID and a couple of 18w flouro tubes and they killed my Grasslin timer after a few months... So, you absolutely MUST have one with any HID I would say - I didn't think I needed one with such a small lamp - WRONG! Be safe people - it's not that much money - and what price safety? Another reason why UK420 is the best grow site you will find... Link to comment Share on other sites More sharing options...
darknightd Posted June 4, 2009 Share Posted June 4, 2009 The easiest way to address this issue would be to buy a timer, if possible, that has an inductive load rated as 600watts. They are available if a little pricey but you wouldn't have to worry about your ballasts kicking in as long as the bulb your using is 600watts or less. Anything above that then i would recommend a contactor. I have a couple of timers and they're both cheap and nasty ones from Morrison's but they handle an inductive load of 440watts which is ideal for my 125watt CFL. The other timer controls my oscillating fan. The nly time that you won't need a contactor is when you don't need a timer. Like when your running your lighting 24/7 for the amount of time of your grow. I will need another timer with a higher capacity for inductive loads but for the cos of them, i will just buy a contactor and a cheap and cheerful timer. Oh, i'm new to this site so hi everyone. Link to comment Share on other sites More sharing options...
scraglor Posted June 5, 2009 Share Posted June 5, 2009 (edited) The easiest way to address this issue would be to buy a timer, if possible, that has an inductive load rated as 600watts.They are available if a little pricey but you wouldn't have to worry about your ballasts kicking in as long as the bulb your using is 600watts or less. Anything above that then i would recommend a contactor. I have a couple of timers and they're both cheap and nasty ones from Morrison's but they handle an inductive load of 440watts which is ideal for my 125watt CFL. The other timer controls my oscillating fan. The nly time that you won't need a contactor is when you don't need a timer. Like when your running your lighting 24/7 for the amount of time of your grow. I will need another timer with a higher capacity for inductive loads but for the cos of them, i will just buy a contactor and a cheap and cheerful timer. Oh, i'm new to this site so hi everyone. HID's are capacitive as well as inductive, so the inductive ratings of timers (and relays and contactors for that matter) is irrelevant on it's own, a timer rated for 600watt inductive load, will still likely weld on trying to run hid's from it. also the inductive rating on timers, is for light inductive loads such as motors and general equipment containing small transformers, not heavy inductive loads such as lighting ballasts Edited June 5, 2009 by scraglor Link to comment Share on other sites More sharing options...
Guest 2hi2try Posted June 15, 2009 Share Posted June 15, 2009 i dont use a conntactor, there again i dont use timers Link to comment Share on other sites More sharing options...
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