digital timer trouble

[beefORchicken]

so I've got some cheap noma digital timers from canadian tire to automate a few things.
http://s7d5.scene7.com/is/image/CanadianTire/0528867_1?$medium$&defaultImage=image_na_EN
running flourescents on one , no prob.
running 2 aqualifters and air pump causes it to reset when the timer turns off
(i notice when it doesn't cycle on again and the clock is reset from the last switch time)
same deal with another timer running a led system (2 adapters)

anyone else have this problem? quickfixes?

[gobytron]

better timer?

[George]

There are no quick fixes. The build quality of these timers is different from one to another. I have a few hardware store timers and one of them resets itself from time to time. I stop using the one that is having problem.
See if you can exchange for a different one from where you bought it.

[Ross]

Hopefully the timers your using are grounded ones and not 2 pole ones that have been modified / bypassed the grounding pin

[cale262]

I've used them in the past but never for anything essential...I personally like the mechanical version better, less $$$, more reliability.

[mike31154]

I've had similar issues with an 8 outlet digital power bar. Timer resets and all the settings are lost on occasion, usually when I've been messing around unplugging things or inadvertently tripping the GFCI receptacle it's plugged into.

There are pros & cons to both the mechanical & digital timers. Most of the digitals will have a backup button battery that is supposed to save your settings and keep time during power outages. This might be a good place to start if your digital timer is acting up, replace the backup battery. A mechanical timer does not have this feature and a power outage will cause it to lose time for however long the power is out.

With respect to the two/three prong issue, the light duty timers, whether mechanical or digital will not have the grounding pin. They are generally made for low power use lighting applications since most night lights only have two prong plugs on them anyway. Some of them don't even have the large/small blade feature which serves to ensure a consistent polarity when plugging in your light. This can be hazardous since the outer threaded socket will be live with the hot line (instead of the recessed portion of the light socket) if the blades are not plugged in with the proper polarity. You'd still have to be pretty careless to zap yourself though. As long as the fixture is unplugged when you need to change the bulb, you're ok. Other than that, it's not an issue since most small appliances these days are double insulated and don't really need the safety ground. Check the timer well before you buy, the light duty can look identical to the heavy duty three prongs. I was just in Can Tire today and there are both versions of the timer pictured in the first post of this thread, which looks to be the light duty one BTW. The heavy duty ones will be a few bucks more though and they will always have the grounding pin, so be aware of that.

[beefORchicken]

iv'e got four of these, none of the things plugged into them need grounds (metal halides are on a heavy duty outdoor 3 prong version) , and these are polarized, i cant go mechanical because i need the 1 min resolution.

ill try changing the batteries. ive also heard that these things have trouble running small/inductive loads (such as pumps), is this true?