IntermaticST01K Astronomic Digital In-Wall Timer

Works great with all kinds of lightbulbs – I tried a couple of others and did not have good results with my LED lightbulbs. Intermatic is the original best mechanical timer – this heritage of using a mechanical type off/on (this switch “clicks” when the internal control goes from on to off) is the reason this timer works with all kinds of bulbs. Unlike some electronic timers – when the Intermatic switches to off the circuit is totally dead. Plus does not need a neutral wire – many older homes like mine do not have a neutral at the switch wiring - so can be used for almost any application. Switches which require a neutral do so because they are using some of the power to operate to switch program - instead this uses an internal lithium battery.The astronomic feature is terrific - it adjusts the dusk and dawn time based on your generic location. Programming is easy – watch the company YouTube. You can program each day or program for “all” days. Then it is just a matter of setting event 1 - which is when you want the switch to turn on - event 2 is when you want thw switch to turn off. In my case I chose on at dusk and off at dawn for some outside lights. Scrolling through the menu is just a matter of hitting the on/off switch .Some revieww comment about the battery – this is a good feature because the battery maintains the programming – if the power goes off the switch still has the programming. The battery is a great advantage and part of the design because this timer switch makes the circuit absolutely dead and does not use the house power to keep the switch programming. I have not had the switch long enough to have a battery go out – the lithium battery should last several years and another great feature is that when the battery is getting weak the switch gives you a low battery warning. Battery replacement is simple from the front cover without removing the switch on the wall. When you do change the battery you do not lose the programming because it has internal memory for a few minutes without a battery installedAnother great part of the design is that pressing the cover changes the switch from automatic to manual to random. So you do not have to flip the cover open to get at the small program buttons to make a simple and more frequent choice – for example when I’m gone I click it to random for a couple of rooms - The timer then varies the preset times - For example rather than going on at 9 o’clock it might not turn on until 915 and instead of going off at the set time of 1100 - It might switch off at 10:45 - so it has more of a somebody is home look.The switches are simple you set it and forget it – the wireless/hub type switches are usually a problem for older homes which just have the hot wire and load wire at the switchbox without a neutral and/or ground . Plus when it comes to appropriate technology – I really don’t want to get on my phone and go through an app and play around with lights all the time LOL.I now have four of these in my home - hope they are like my last Intermatic mechanical timer switch - It worked every day for 40 years - This is a brand which I trust. So I totally recommend these timer switches.

I purchased this ST01K to replace an Intermatic EJ500 timer installed in 2007 that began acting erratically when I switched the outside garage lights to LEDs -- sometimes they would flicker or they would fail to either turn on or turn off. Turns out the EJ500 is intended for incandescent bulbs only and not LEDs. This model cures that.I first followed the written installation instructions but I had some difficulty with them, getting off stride with one too many or one too few On/Off presses during the programming step (see my "Final Note," below). The instructions were also silent on a few items, like the device supports an Auto Random function (in addition to an Auto function) to slightly vary the on and off times for a "lived in" look, but I couldn't find any mention of it.Because the ST01K is battery-operated, it's possible to program the device completely before installing it in a switch box. That's much easier than doing it after installing it, as the keys are small (by necessity) and the narrow readability range of the LCD display means you have to bend over at the waist or sit on a stool to make the characters legible while you're programming it. All while holding and reading a wrinkly page of closely spaced instructions written in small type. Far easier to do at the kitchen table than at the wall switch.My only other difficulty came with recognizing when the switch was on or off (and at the kitchen table there was no light hooked up to tell me it's on or off). The EJ500 had the words "ON" and "OFF" lit on the display for each condition. Not the ST01K. It's got an icon of a light bulb in the upper left corner of the display, whose content is either clear or black. But there's no mention of it in the instructions or the meaning of the clear/black conditions. I guess they figured it's intuitive, but they didn't count on my lack of intuition. A few presses on the On/Off button and a welcoming click from the device and a change in the condition of the icon confirmed the bulb icon indicates the switch is on or off. Fine, but which is it? It took this dummy a while to conclude that when the bulb has a clear center, the switch is on, and when the center is black, it's off (I guess black is "dark" and that means no light. Duh.). A single sentence in the instruction would have avoided my confusion.Other than that, the electrical hook-up in the switch box is straight-forward and shouldn't cause much difficulty. It's installed and working fine and I can go back to ignoring the garage lights.Final Note: You can ignore the written instruction sheet and instead go to "YouTube.com" on the internet and watch an Intermatic employee go through the complete step-by-step programming sequence. At YouTube.com, search for "ST01K Astronomic" to find and play the video. Simple once you see it done. He proceeds slowly enough that you can follow along at the kitchen table programming your device as he programs his. Smart thinking at Intermatic and they get my applause for providing the video.

I purchased this timer to replace an older EJ500 timer that started to sometimes skip turning on at night and refused to adjust to daylight savings time. The installation was very easy considering that the color coding of the wires on the SK01K timer was the same as the older EJ500. I did install it as a component of a 3 way switching circuit and it worked great. Then came the problem....Programming the SK01K. The setup instructions were very straight forward and after looking up my longitude and latitude the clock worked perfect. Then you got to the programming step which was a confusing mess. After watching a couple YouTube videos I finally got it to work from Dusk till Dawn. I do like that you can set the timer to your exact longitude and latitude and that, since it is battery operated, you can program it before you install it. Be careful when you open the battery compartment to install the battery, it is somewhat hard to get the cover off and since it is plastic you can't just strong arm it. I did notice that the Intermatic website sells replacement battery compartment covers and after prying off the cover to install the battery, I can tell why. The instruction sheet was printed in a very small font and I ended up downloading it in a pdf file from the Intermatic website so I could zoom in and read it easier. If you purchase this timer have some patience and watch some YouTube videos to help program it. I hope it lasts as long as my old one. Shipping was quick and it arrived undamaged. The box included the timer, wire nuts, electrical box screws, a CR2 battery, instructions in multiple languages, and a jumper wire for the 3 way installation.

Does what it is supposed to - I like the timer for lights. Had a bit of difficulty getting it set up at first but it has been great so far - have had it about a month.

Works great so far. Easy to set timer if you have ever set a plug in electronic wall timer. Piece of cake, but take notice the 7 day program starts on Monday. Wiring in was a different issue. As I only had a 2 pole light switch, the instruction were not very accurate to hook this up. I went on internet & found a sight on how to wire wall timers. It actually listed this brand as well. They were step by step clearer. Followed that & bingo, works perfect. It was just a matter of having red wire going to correct wire from wall. Love the random on/off setting for better security. Found same product at local hardware store but at a higher cost.

The unit works great. The battery is a great feature since my previous timers didn't have a battery backup so they would need to get re-programmed when the power goes out, even if it's momentarily which is a huge pain. A few things they could do which would make this a 5-star.1. Add an optional neutral wire so that the battery can be used only when power goes out and can also run without a battery2. Put a backlight display3. Improve the user interface for programming - it sucks.4. Improve the overall user interface - allow a user to review what time the lights will come on and off easily vs. going back into programming mode. Hire a UI/UX designer4. Add a battery life indicator so the battery doesn't just die without warning

Does not work even on an older house. The supplied CR2 battery is low. When it is hooked up, the switch keeps randomly resetting itself. After I disassembled the switch it was saying low battery and resetting all by itself. Do not waste your money it's not worth it.

This timer does take up quite a bit of room in the wall box so you have to get other wires out of the way. The existing outlet box I installed this device into has three separate switches that control different lights. I called Intermatic customer support and they really helped me figure out the wires. I did need to have a multimeter to work along with the telephone support. Programming the timer prior to installation was a good idea as the screen on the timer is small and awkward to read when installed on the wall.