TN311 Heavy-Duty 24-Hour Indoor Plug-in Timer | Customizable Daily Scheduling with Efficient Control, for Lighting, Fans, and Small Household Appliances, 3 ON/OFF Events

These are, as far as I know, the only timers that have designated "on" trippers and designated "off" trippers. I plug my crock pot or other device into this when I want it to turn itself off if I forget to do so. So, I just install only one of the "off" trippers. I place no other tripper on the wheel. I use the manual switch on the timer to power up the crock pot and set the "off" tripper at some time when I want it to turn off. Then, if I am going to be really late coming home, I know it will shut off before a dry crock pot starts blazing. And, because I only installed an "off" tripper, it will never start up the crock pot again on its own. Other timers that have trippers have trippers that are all the same. If I used one of those, then the timer would turn off but it would also start up the crock pot the next day when that tripper was encountered in the next 24 hour cycle. I like to slow cook meats over 12 or more hours and I put it out in the garage so it doesn't stink up the house. (Lots of spices, chilis, and onions slow cooking over many hours can impregnate your drapes, carpets, and woodwork with aromas that won't go away for days and days...so I put it in the garage.) I could certainly envision a day when I set the food to cook, but I would get called away on a late night job, It would be just like me to come home tired, go to bed, and forget entirely about the food cooking in the garage. In good weather, I'll park my car outside. It could be days and days before I remember the food in the crock pot out in the garage. With this Intermatic timer, no problem. Fire department didn't have to come. It shut off the crock pot and won't start it up again, and again, and again like other timers would do. These timers will work with inductive, resistive, magnetic fluorescent, and electronic fluorescent, including twistie bulbs. It's got a 15 amp 3 prong outlet. Motor turns the wheel. Simple. Reliable. I like it. The operative logic of such a simple device is bullet proof. What if the power goes out? It starts up again when power is restored. But, oh, you say, your food will be rotten if it's off more than a half hour? No problem, Just look at the wheel when you retrieve your food. You set the wheel for the correct time when you started cooking. If the time is off more than whatever period you think is unsafe to eat? You will know.

Works well

I got this because I have a wall mounted swamp cooler that cannot be programmed to turn on or off. (I first heard about this device from reviewers that owned food dehydrating machines that did not come with an automatic off option, and they would remedy it by plugging in dehydrator into a timer and set it to turn off after set hours). This is simple, yet useful. The timer on the dial is not accurate to the "T" but it's close enough and good enough. I got tired of coming out to the living room in the middle of the night, shivering, because the swamp cooler would get our house too cold by 2am, but it's just too hot here in the evening (bedtime) to shut it off, and this was the solution for me. I only need one set of red and green for now; have it go off at 1am-ish and come back on at 9:30-ish in the morning.. (Not to mention there's the on and off switch on top in case I just want to shut it down) but during the winter when I am not using the swamp cooler I may use this for some other appliance.. not sure what yet. As of writing this review I had this unit for 3 months and it's been working without failure. Also, I like that it directs the plug to the side to the right (as you can see in the pic) so that it would make whatever plug fit behind furniture or tight spaces. If there's only thing that makes me question it, is when it goes from off to on, I see a contained, but visible static spark sort of inside the dial up on top. I'm not sure if that's just normal or a hazard since I'm not an electrician. I will post that question on the review page and see what others say.

I have one of these babies turning the lights on my terrarium on and off reliably and quietly for 15 years, but it should be said that another one did become quite noisy after years of use and they are not terribly precise timekeepers; nor do they permit complex programming or even more than two on-off cycles per 24 hours. But the rugged reliability is worth a lot. I went to Lowe’s to replace the noisy one and bought an Intertek 24-hour mechanical timer because it was what they stocked (see photo and Intertek 24-Hour Indoor Mechanical Timer). Well, aren’t they all the same, basically? No. The Intertek failed in 6 months so I bought another and it failed after 18 months. And even when working its override switch simply turned the light on, full stop. You must then turn the light off manually. The Intermatic override switch lets you turn the light on early but keeps the “off” timer in play; it also allows you to set two nighttime “off” times and use the override switch to turn it back on knowing that the second “off” time remains in play.

A great product easy to set the time for whatever you want to turn on and off if you are away or for a Christmas tree, it’s been a terrific product

A little device that works great, so quiet too.

so far so good, works as advertised for my veggie led grow lights.

EDIT 7/21/15 - The switch in this has started throwing off violent sparks for some reason. One of the sparks melted one of the sharp plastic activation points on the switch wheel, so now it skips an activation every 6th cycle or so. This entire timer lasted less than 2 years. Into the trash it goes. I found out you can get a much better electrical timer from Harbor Freight for 5 dollars. EDIT 5/30/14 - To fix the grinding noise this thing starts to make, soak the entire timer in mineral oil. I used an old plastic butter tub I cleaned out. I filled that sucker with mineral oil (about a dollar for a bottle from walmart) and dropped the timer into my vat of oil and let it soak for about a day. I shook off the excess and dried the outside. It is almost completely silent now. If I have my ear pressed to the machine I can barely hear it, you would never notice it otherwise. It's totally perfect now. I'm still leaving a star off because they should have lubricated this at the factory. It didn't break and still conducts electricity etc, timer is still fine. However, the instruction sticker on the back did fall off, but it's not particularly useful anyway. Keep in mind I said MINERAL OIL, use of gasoline or kerosene or some other kind of volatile oil is a recipe for a house fire. Mineral oil is non conductive and doesn't hurt most electronics. They even have computers where you submerge the entire motherboard in mineral oil as a form of liquid cooling. Older Review----------------------------- This started making noise after about 4 months of use. Its not deafening, but you can hear it from across the room pretty clearly. There is no way in hell I would use one of these in my bedroom, for instance. It still works though. Still keeps correct time. You aren't supposed to place the plastic trippers next to each other, so if you think you are going to get a 5 minute interval out of this guy you have another thought coming. There is also no place to store the extra trippers you aren't using. I just scotch taped the extras to the side of the timer.

works as expected

Usando este aparato me da la tranquilidad y confianza cuando dejo programadas tareas de algún aparato en el hogar, como las luces de navidad al programar el inicio y fin del paso de la corriente eléctrica, es durable y resistente, no presenta sobrecalentamiento u otras cosas, lo recomiendo ampliamente por su fácil uso en el hogar. Gracias =D

I ordered this as an exact replacement of the timer we used for about 10 or so years, without issue. When the original one quit working, there was no question as to what the replacement would be. The ground plug feature is important to us because it is used for our commercial grade coffee machine. It keeps very accurate time. It’s so easy to use the pins to set on and off times and anytime there is a power failure, setting the current time is as easy as turning the dial - couldn’t be easier.

Muy bueno

El Intermatic TN311 Temporizador, es sencillo de instalar, trabaja muy bién, se programa la hora de encendido y apagado, se conecta, y listo! Funciona de maravilla.