Intermatic ET8215C Time Switch 2-Circuit/30-Amp Gray

I now have a few of these Intermatic astronomic timers, on some lighting as well as a solar water heater control. They work perfectly and have pretty good versatility in terms of programming. Never have to change the on and off times as the seasons change since it knows when sunrise and sunset are. To me they are expensive but the best or only choice I could find to fit the application. I'm surprised they haven't figured out how to make an app-driven configuration setup, which might be easier than the on-screen arrangement. You probably need some basic electrical skills to understand which model you need and how to wire it, for 120/240, single or double pole, etc. Recommend these if you want the astronomic control feature.

Best design of an electronic timer. Never have to reset the timer with the time change as it automatically changes by itself. After entering the date, time, and location, the timer has the time of sun rise and sun set programmed in its memory, so you don't have to keep changing the time every few months. Intermatic is a heavy-duty timer with NEMA 1 and NEMA 3R boxes to choose from. I only wish they offered two AAA lithium batteries for memory battery backup. I always install energizer lithium for areas prone to power outages, so the timer keeps its date and time.

The wiring diagram for this thing is awful. I work professionally as an engineer and I'm accustomed to looking at diagrams all the time. There are a number of different ways you can interpret their poorly designed diagrams.In my situation I was running two 30 AMP 120V circuits to the device. This is a simple setup, and I bought this model specifically because it was advertised as 2XSPST. A few important notes:Disclaimer: For informational purposes only, I'm not a licensed electrician and don't warrant the accuracy of the following:1)Timer power has nothing to do with the delivery of power to the device on the opposite side of the timer. When you bring your feeds in, wire it up, but understand it's independent of everything else.2)If you're in a 2xSPST configuration(120v), 3 and 5 are for your incoming(line) hot wire(3 is hot from your first circuit, 5 is hot from your second circuit). 4 and 6 are for your outgoing(load) HOT wires(4 is fed from your first circuit, 5 is fed from your second circuit). Wire the neutral for your first circuit (whose hot is in 3), to the neutral for feed one(whose hot is 4). Repeat for the second circuit. Wire the grounds the same way. In my case each feed was 30Amps on the main panel, and fed separate small sub panels that would be switched on by the timer.I would have rated this higher, but I'm disappointed in the instructions. Also, if you're running two 30AMP circuits into the timer, you're using 10 gauge wire. There isn't a whole lot of space in the timer box for two lines coming in and two loads going out(12 10 gauge wires total).

This timer works great, but there are a few minor drawbacks.1. The batteries have to be replaced every 3 years. It would be better if it came with durable lithium batteries that last 10 years or more.2. The battery compartment is difficult to open.3. There is some ambiguity in the manual; the help line resolved this.4. One has to remove the module from the metal box to reprogram the switches to work simultaneously. One then moves a circuit board jumper.On the positive side:1. The timer keeps time even when power is lost. (Of course the load will not be powered when there is no power.)2. The astronomical feature means that the timer adjusts the dusk (on) time and dawn (off) time based upon day of the year.

The unit works great and was programmed to come on at dusk and off at a set time. The programming was a bit tricky, but only took a few cycles through the menus to figure it out. The instructions for wiring were less than clear and did not reflect the proper wiring method for the desired loads and switch settings. After making my own jumpers, the box worked great.