Light Keeps Killing Timers

[scraglor]

they have a high powered relay built in, so thye're good enough, but will where out, where as properly rated lighting contactor should last decades

[dickcheese]

I use plug n grow timer think they have there own contactor built in dont they?? Well at least I hope they do

i have two im sure they have a built in contactor

[scraglor]

.

Edited March 22, 2013 by scraglor

[GTWMT]

yeah.. tbf that's really really dangerous, you should be using a contactor.. but its all god as they are only like 15 bucks..

[Peregrine]

This should do the job...

• Designed to take high loads;
• Normal household timers are not built to take the high inductive loads produced by HID ballasts. If used with an HID ballast, the contacts inside the timer that open and close the timed circuit will overheat and weld together, breaking the timer and leaving your grow lights permanently on;
• The LUMii Heavy Duty 24 Hour Plug In Timer is different - as the name suggests it is designed to take high loads and has no problem dealing with the inductive loads produced by a 600 watt ballast. This means no separate contactor is required, saving you money;
• There are 96 switching operations within a 24 hour period (every 15 minutes); Heavy duty contacts mean it can take high inductive loads. It is suitable for timing 1 x 600w HID ballast or up to 6 x 200w CFLs. It is very reliable and has a high quality timer unit with a robust 'inline' case design with socket and timer dust covers.

Edited June 6, 2015 by Abe Froman
to remove spam

[Peregrine]

I just bought me a Davin DV-12 which is a time-controlled relay box. 59 euros.

Just finished installing it. It will support 2x400w or 2x600w(which is what I have connected) but works also with just one HPS bulb if that's all you have. Quite useful if you plan to have 2 lights at a later stage.

It's plug and play basically with a built-in timer, just mount it on the wall, plug it in, then plug in your ballast.

I had a problem with timers failing due to the 600w so this should sort it out.

Have to say I was getting concerned about the fire risk, not to mention a growing list of ruined timers.

[Wiggles41]

Get the digital timers from Argoos Beenusing em for years, ALL mechenical timers are no good for us growers.

You will get 2 timers from Argoos for 10 - 15 squidm best deal in town

nice bit o' troll-baiting mate

[Peregrine]

Struth, now the DV-12 keeps tripping. 3 times yesterday and already once today.

The DV-12 has a built-in 6 Amp thermal fuse which shuts down the DV-12 automatically in case of an overload/short circuit.

So, time to call Sparky methinks.

[cressman]

Hi all, I have been looking through this thread and I have got a little confused.

I have an envirolite CFL 250w with reflector etc and a Grassline mechanical timer, do I need a contractor as well? or is it safe combo without?

[scraglor]

contactor, a contractor is a person you hire :/ you "should" be fine without a contactor but better to have one

Edited April 13, 2014 by scraglor

[craigfjyp]

Definately just a matter of time untill your timer goes wrong possibly burning down the house and killing you. You certainly need to run any high voltage equipment through a relay switch so the timer operates that and the high voltage runs through it and not the timer itself. For me its well worth the fifty quid or so for the proper thing. I killed many timers before I found out about the relays, luckily never killed myself.

you can get a 2 socket contactor from hydro shops for £25 mate...its worth investing in one.

[Saddam]

you can get a 2 socket contactor from hydro shops for £25 mate...its worth investing in one.

I think Forest Dog might've sorted it now mate, this thread's over 8 years old!

[stu914]

@@Saddam

[Indicaderek]

Low power lamps not requiring a contactor relay? (Think again possible 17amp+ inrush currents across all growlight types, HPS - MH - CFL and even LED arrays)

Been reading an article about 20watt CFL's, no contactor relay needed? Think again, some of these little lights can draw upto 17Amps at switch on due to inrush currents with a duration of 300 microseconds, this is more than enough to weld the contacts on even a 10amp contactor relay in some cases, this is more likely when you have short cabling to your lamps as longer cables increase the resistance reducing the inrush current, I myself was surprised at this issue with tiny CFL lamps and can only put this down to poor electrical design in the lamps starter circuit, in conclusion if you are seeing timers fried that are running CFL's get another brand of lamp that is hopefully better quality along with a good quality contactor relay and maybe just fit a relay contactor as a precautionary measure even if you aren't having issues with timers.

Article source on CFL's is from a reliable, digital electrical/electronics wholesaler who did run tests on these lamps with the alarming results, after contacting the lamp manufacturers they were told that the lamps drawing these huge inrush currents are working as intended! If you want to read the article yourself google 'compact-fluorescent-tribulations' as this is the article title and comes up as one of the first google results though some lamps may not suffer this issue some certainly do and its very much a case of better safe than sorry especially when a basic relay contactor can be purchased ready to go for £25 which is a whole lot better than burning your crop and home!

Low power sodium or halide lamps also have large inrush currents in my experience, I used to run a cheapo highbay 150w M/H light that fried several timers and welded the relay contacts, once I had read and learned about the issue I got a contactor which is still running today and working nicely with my recently purchased 250w ballast, before this I was oblivious to this issue hence the fried timers though I should have known better having studied electronics at college.

LED arrays: 1000w array that draws 380watts power? Stated worse case inrush current on a 230V AC mains supply at switch on is over 46 amps! This from a manufacturers website! This is a worst case scenario but once again bears out the necessity for a contactor relay regardless of lamp type and wattage used, said manufacturer also states that placing a few of these units on the same supply can increase this inrush current to over 100Amps. Any reputable manufacturer should publish the inrush or starting current measurements for any mains operated electrical grow gear including lamps, ballasts and even fans which, having a capacitor to start them may also draw substantial current when switched on.

A surge protector may also be useful too as it should trip in most cases when these huge amps are drawn at switch on and may prove to be a viable test to check CFL/HPS/MH and even LED lamps for these huge transient current spikes.

A few other notes on general safety and fire hazards as just last night I took a peek at a mates grow set up (which prompted this post) and almost had a fit when I saw plants 3" yes a whole 3 inches away from his 600w lamps in his loft grow, needless to say said plant was frazzled like an overcooked crisp and a serious fire hazard, I dread to think what may have happened over the next few days had I not kicked his rear about tying them plants down, this would be laughable had this not been so hazardous. Said mate also gave me an old reflector he had kicking around after I did him a favor as I needed a reflector, I did a full check on the wiring and found the earth wire was completely detached under the lamp socket where it was supposed to be attached to the aluminium housing as the small nut and bolt had come off and were rattling around inside despite the barbed locking washer, I refitted the earth and used nail polish to lock the threads in place which works very well and being an enamel type paint is rather handy in being reasonably heat proof, cheap and fast drying, mentioned this to me mate who was totally oblivious to this hazard. After this crop my whole wiring will be stripped and checked internally for any wires that may have worked loose over time and I would recommend this check for anyone growing indoors annually or after every harvest, if you don't feel up to doing this yourself get an electrician or other competent person to check this for you as a 240 volt shock is nasty and losing your home to a fire is preventable in most cases.

[Davey Jones]

Derek

theres plenty of crap in that post, it sounds like they are tyrying to sell you something but if you look at Hank Wallace you will see he doesn't work in power electronics or anything close to mains, he is involved with software and music

All this talk about inrush currents but nothing about inductance or capacitance I am sure Hank is a knowledgable chap but the fact is he selected a relay for incandescent lamps but paid no attention to the power factor of CFL's (he even admits this) and you can bet your bottom dollar if he had seeked out this info then it would be there if it wasn't then pick another that does have the info, designing commercial electronics requires documentation

You talk about these inrush currents but you clearly don't understand, are these inrush currents OK to supply through a 13A plugtop? everything has an inrush due to parasitics its the energy let through (I^2*t) that matters

Are you saying we all need dedicated supplies to our grows? on that note are you saying plants are flammable and if they get too close to the lamp they will burn the house down?

E2A

A surge protector protects against transient voltages not inrush currents, they use metal oxide varistors (MOVs) and transient voltage supressor diodes (TVS)

When you EMC test one part requires to you supply transient voltages, its called fast transient bursts

http://www.compliance-club.com/archive/old_archive/010619.htm

You can actually hear the devices snapping into action if you design them right and it warms your heart, they do jack shick against inrush currents that requires different components

Edited June 6, 2015 by Davey Jones