Home Automation

The WebCell was designed to be the central control element for home automation applications. We have developed a comprehensive set of web pages that interface to INSTEON home automation products.

Benefits of the WebCell for Home Automation

Your typical home programmable thermostat allows you to set a different schedule for weekdays vs. weekends.  It may let you change the temperature setting two or four times a day for each schedule. And how do you set this information? Up/down buttons. Up/down buttons to select a time. Up/down buttons to set the heating temperature. Up/down buttons to set the cooling temperature. Then move on to the next setting or day and repeat.

What about your irrigation controller? Set the start time with up/down buttons. Set the zone watering times (for 6, 8, 10 zones?) with up/down buttons. Maybe it has mutlple schedules, so be sure the one you're setting is the one in effect.

Instead, how about a web page with the entire thermostat schedule displayed at once? Directly enter time or temperature from your computer, tablet, or smartphone. Create as many or few changes per day as you need. Checkboxes select the days of the week, and you can have as many different day-of-week schedules as you want. Get up earlier on Wednesdays? No problem. More than one thermostat? The WebCell can handle nine zones, all displayed together on a single web page.

The irrigation schedule is just as easy, all laid out in front of you. If weather requires adjusting watering time, enter a percentage and see both the original and new active time listed for each zone. For testing zones and winterizing, you can use your smartphone to turn on individual zones while in the yard (as long as you're in range of your home Wi-Fi).

You can create multiple schedules and select which one to put in effect. Leaving town? Create an "away" thermostat schedule and turn the furnace off while you're gone. Hot summers? Create separate spring and summer irrigation schedules. You can even schedule the change of schedule -- automatically kicking in that summer irrigation schedule on July 1, for example.

There are no screen shots here because you can try it out yourself -- just go to the Downloads page and download the CellScript Simulator.

Assembling an INSTEON System

The primary source for INSTEON home automation components is Smarthome. Besides the WebCell, the starting point for creating a system is the INSTEON modem. The modem takes commands from the WebCell and relays them to the various INSTEON devices in your home using radio or power-line signals. The Smarthome model 2413S has a serial interface for connecting to the WebCell.

Next you choose what you want to put under control of the WebCell. You can swap your existing thermostat with an INSTEON thermostat, which is intended as a drop-in replacement. We've used the Venstar T1700 combined with the 2441V INSTEON adapter, both from Smarthome, but we're confident the newer 2441TH thermostat would work as well. For irrigation, we've used the Smartenit 8-zone controller, item 31270 from Smarthome (if you have more zones, you can add more controllers). And there are quite a number of power and lighting switches and dimmers, which can take the form of a wall switch or power plug.

Choosing a WebCell

A home automation system can be built around either the basic WebCell or the Cell Development Kit.

Cell Development Kit

This is the easy way -- just plug in connectors. You need a USB power source (maybe a spare phone charging block?). Plug the USB cable into a USB power port, and plug the network cable into your network router (both cables provided). The INSTEON modem comes with a serial cable that plugs directly into a serial port on the kit. That's all there is to it.


You can save some money with a little more technical knowledge and some soldering, but if there is any of this you don't understand, you probably shouldn't try it. First you need a 3.3V power supply -- we've used a wall adapter from Jameco Electronics, part no. 251565. You can clip the end and hard-wire it, or attach a matching jack to the WebCell.

Then the logic-level serial port on the WebCell needs to be converted to RS-232 levels. We've used a converter from NKC Electronics that also provides the proper male serial port connector -- their part no. KIT-0101.

View photo of example