Digital timers verse's mechanical

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Jan 31, 2011
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Hi everyone. I read somewhere that mechanical or analog timers wernt as good or say acurate as digital timers. True/false? doesn't make a differance? Thanks everyone. Hero
Analog timers generally have narrow or fixed frequency and on/off cycles, whereas digitals generally are the opposite.

Ensure that the timer is capable of switching the load, a contactor is a decent investment if you are switching big loads.

Nothing gives a grow away like the building burnt down around it and you wouldn't want that over a few dollars.
I started my grows with digital timers and contactors but recently moved both my HID lights to mechanical segment timers.
They may not be as accurate but they are more reliable IME since 2 digi timers "lost" their settings and reset on me leaving a lights on for 4 days before I found what had happened! The other resulted in the timer for a flood & drain pump not turning on.

A new item on my daily checklist is to check the timers are all functional!
Peace W
Thanks everyone.. I am weighing out which would be better. In one of the stickeys.. I think it was here the person wrote to go ahead and get a digital timer because they are more accurate or something.. I wanted to know what the majority use.. Thanks again. Hero
Digital's don't play well at all with CFL's and T-5's.

I'll just stick to my tried and true mechanical time switches.

The one I use for my lights is the same model/make as one that has been doing yard light duty for close to 40 years with no problems and still is.

I'll chime in here. Analog timers are slightly less accurate and will not automatically reset in the event of a power failure. The clock just stops running so it will still be on the correct amount of time just not at the right time. Digitals usually have a back up battery to save your settings and the correct time however they are generally less reliable.

I use an Intermatic t101 for my lights and a Paragon(very similar to the Intermatic) for my fan. These were originally analog swimming pool pump timers and just what I happened to have around. Their digital counterparts are alot more money and just not as reliable (they tend to lose programs). Although an Intermatic PE153 digital 3 circuit timer would be nice, imo it would eventually fail to turn something on or off causing me a problem.
LOL, that's funny.

The timer that runs my lights, along with the one doing the 40 year, continuous yard light duty, is the very same. Intermatic t101.

Simple and bulletproof.

My light are wired into the electric so I dont really use times... but the ones i have always used are the mechanical and i have never had one go out on me.
Thanks everyone, Think I will keep it simple and go with the mechanical. Appreciate it. Hero
ok.. mechanical timers aint bad.. best to use them for light cycles.. 12/12, 18/6... because most of these use increments of like 15 mins or whatever.. so to set something like a light cycle it works great and is hard to mess up...

The downside of mechanical timers are this.. if you bump into them you might turn the timer and mess up your cycle.. if you bump it you might knock down some of the pegs and mess up your cycle.. if you use for small things such as co2 or water pump, you cant set them to do exactly what you want.. ALSO, most digital timers have back up batterys in them so if the power goes out they will keep the time and keep your cycle exactly where it is.. mechanical timers just stop when the power goes out.. and when the power comes back on they start back up.. so if your power goes out for a few hours and you dont know it, this could mess up your cycle..

Digital timers are great.. you can make them come on when you want and go off when you want.. exactly when you want.. you want your co2 to come on for ONE min. exacly?... (1on = 3:00pm) (1off = 3:01pm) and there you go.. very easy to use.. most have at least 20 on and off settings.. so you can do ANYTHING you can really think of with it. You want to use a timer to drip feed your plants in soil you say?? digital timers can be set to come on any day of the week you want.. any combo of days.. so you can use them to feed soil plants one time, for 5 mins, every 3 days, if you want.. Also Like i said before, they have a battery to back up the power in case they loose power.. this keeps the time rite even if your powers out, so your cycles will stay the same..

if you do NOT hit the reset button before you set up your cycle on it.. and you do not go thru all 20 on and off settings, you may have one on there that someone else programed on it and not realize it. This happend to me.

I set "on1 everyday 6pm" "off1 everyday 6am" 12/12 cycle for my lights.. i put my lights on this timer and let it rip.. 2 weeks into flower i realized that "off20" was set for "everyday 12am" so my lights were geting cut on at 6 and going off at 12.. really messed up my whole crop... so HIT THE RESET BUTTON before programing.. peace
Anyone mind explaining the contactor a little more? I've used a cheap mechanical in the past with no problems, only switching 92watts of cfls. I'll be running a 150watt hps next...dunno if I should be worried.

In reference to bleek's post above, I had mine pushed to close to the wall one day and the timer nub got caught up on the wall trim. Messed up my cycle for a few hours
The timer relays power to the contactor, which is basically a very heavy duty electrical switch that is usually capable of handling more juice. (in simple terms)
Cool thanks man, im gonna see if my timer has any specs on what it can handle
I use mechanical, but just had to buy 2 more. When I hooked up all my new lighting, I didn't take into account it was too much for the timer, which failed! Luckily, I was standing there waiting for it to turn off when it didn't......

Oooops....we'll chalk that one up to a stoned moment!
A good timer will be 15 amp, dont put more than 12 amps through to be safe and you'll be fine.

Dont mix digital and mechanical timers, go one way or the other.
The back of mine states 1725w....stopped working at 2800w....
Underloaded digi's here, programmed according to the directions. Knock on wood, I've never had a problem.

If you need to time things to the minute, go digi. If you aren't concerned with accuracy within a 15-minute time frame, go analog.

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