Timer failing 'on'?

[VAtransplant]

So.. I flower 9pm->9am and somehow misplaced my Hydrofarm timers a while back, so I've been using a Utilitech 15 amp dual-output digital one with success running a 600w digi ballast for the last 50 days of flowering.

Last night I hung another 600w HPS in an adjacent tent and turned the timer off with the 'on/off' button to do some work without being blinded, and to connect the second ballast to the same (once again, dual output) timer. These ballasts clock in at ~650 watts each on a Kill-a-Watt so I figured that'd be fine on a 15 amp timer, on a 15 amp circuit shared only by a few circulation fans.

Job done, press on/off button for the timer to resume its normal schedule and run until 9am now with two flowering tents. Everything powered on fine and I checked it every few hours until the wee hours of the morning to make sure the cords and timer weren't getting warm, no smells, weirdness, etc. Screw me for not checking at 9am when I took off for work, because the lights stayed on all damn day.

Seems like the on/off button no longer works and the clock has advanced 15 minutes in to the future. Guessing the extra load of the second ballast made it take a dump, but dammit! I'll have run a 48 hour light cycle on day 50something of flower! I don't see much sense in giving them 3 hours of darkness now before their regularly scheduled cycle.

A) definitely going to splurge and get an Intermatic heavy duty timer, B) definitely throwing this one in the trash and using another spare digital timer I have until I can get the Intermatic, and C) definitely crossing fingers that this isn't going to boof my 3/4 done girls.

Has anyone had this happen? I figured a timer could get warm, smoke, erupt in flames, shut off, that kind of thing... not get stuck permanently on. Dammit!

 

[OldPhart]

Any of these digital timers can fail on or off, because the relay in them are far too small to be turning on/off heavy lighting loads. I would say these 15 amp timers are not good for more than about 600W in the real world. I preach this over and over, but I don't like hearing the stories of people nearly burning their house down with a 10 dollar timer. Here is my solution to the problem, use a slave relay controlled by the timer to drive the lighting load. I went pretty overboard with my controller, but I only wrapped up about $100 in it. I have absolutely no fear that anything will now be able to burn my place down; well other than the inherent hazard of an HPS lamp. I use heavy duty (30 Amp) contactors to switch any load heaver than a cheap aquarium pump. I have not installed the thermostat or the heating contactor yet, that is what the open space in the box is for.

The top timer is for the light, and the bottom timer is for the irrigation pump. The outlet on the bottom right is for the lights. One of the orange cords connects to a 3000VA APC UPS unit, and provides power to everything but the heat/cool. The other cords connect to the window AC and the wall outlet to power the AC. I'm using the built in thermostat, set to heat mode, as a high limit and have it set to 90 degrees. If it exceeds the set temp, it will shut off the light for 10 minutes or until the temp gets below 85; which ever is longer.

 

[Phaeton]

I run a total of 17 timers, counting fans. Only one of them has more than 400 watts hooked up and all are rated 1875 watts. Each has a surge protector on the input side.
I have a single 600 watt ballast for a bulb I could not get in 400 watt. I used to run a 400 watt ballast and a 125 watt fan together but no longer, 400 watt max per 15 amp timer is it.

Digital and mechanical are the same, it is that tiny relay that is no way suited for 15 amps, not even close. The 600 watt ballast took out a timer in the first two years, the 400's are still good after five.
I use a 3/4 hp fan (650 watts) and it does not break timers, but it is rarely used every day, the timer is for when I forget to turn it off before taking a nap.

 

[VAtransplant]

OldPhart thanks, that's exactly like something I would build. I even have the inkbird temperature controller you used, controlled my intake fan before I upgraded to an 8" exhaust (no need for intake fan anymore..)

and thanks Phaeton... 17 timers... here I was apprehensive about running more than one because it's two things to keep in sync, but having one cut on a minute earlier than the other is better than overloading a single and risking no lights, lights stuck on, or fire..

and come to think of it, it'd probably be better to stagger two timers a little just to break up the starting draw of the ballasts, which I admittedly haven't measured.

 

[Floridian]

Nothing is going to happen to your plants it takes a lot more than that to throw them out of whack.A lot of good suggestions here but If that is going to be the totality of your load,an Intermatic mechanical timer is what I'd go with.Mine has worked flawlessly for many years with a bigger lighting load than you have

 

[Phaeton]

... 17 timers... here I was apprehensive about running more than one because it's two things to keep in sync, but having one cut on a minute earlier than the other is better than overloading a single and risking no lights, lights stuck on, or fire..

and come to think of it, it'd probably be better to stagger two timers a little just to break up the starting draw of the ballasts, which I admittedly haven't measured.

Back when they were all mechanical timers with each click equaling six minutes it quite time consuming to sync them all. Setting them all the same put them withing six minutes either way. Going into the room before they came on and unplugging each timer as it cycled on then plugging them all back in quickly when the last one lit. That usually would put them within a minute or two.

With digitals I set all the timers to my pocketwatch within three or four seconds. This gives the room a soft start over the first thirty seconds.

Driving lights on the car always have a power relay handling the load, on/off switches burn out really fast with 12v running 15 amps. 110v switches running 4 amps last lots longer.
I agree with Oldphart even though he puts the relays in sooner than I would, I admit to procrastination.

 

[GOT_BUD?]

Hey OldPhart,

What 120 volt relay did you use? I want to build something similar to what you have there to flip flop a couple of LED lights on a single circuit.

 

[OldPhart]

Hey OldPhart,

What 120 volt relay did you use? I want to build something similar to what you have there to flip flop a couple of LED lights on a single circuit.

I just used a cheap double pole contactor, Packard C230B. This would not work as a flip/flop, you would need something more like this. https://www.amazon.com/Siemens-3TX7130-0DF13-Contacts-Contact-Voltage/dp/B0091WMRL8

I really like the enclosed relays, with the heavy lugs on them, but I didn't find any enclosed double throw relays. Well unless you go down to the 'IDEC' or 'ice cube' style relays that you put into a socket. Depending on your loads, a simple 'IDEC' relay may serve you fine for many years. https://www.amazon.com/IDEC-RH2B-UAC110-120V-POWER-RELAY-120VAC/dp/B008FM4CZO I wouldn't have any issues switching 5-600 watt @120v with that relay; or 1kw lights at 240v, I used them a lot for that in the past. It was nice, because I could fit all the relays I needed into a small sub-panel with two lights/relays per 15A breaker and easily switch 8KW with a simple digi timer, with two left over 120v circuits to run fans on... all plugged into a range or dryer outlet What ever happen to everyone trying to use the range and dryer receptacles to run their grows? I spent a lot of time preaching the difference between ground and neutral to people. I don't see a lot of talk of people doing this anymore.