setting alarm settings on ds10s20 sensors

[mnsandler]

This limit logic is designed to generate an ON pulse between the time a temperature rises past the second limit and then decays below the first limit. It was built so I could use a temperature sensor to detect when my gas water heater is heating the water rather than burning the pilot. The sensor is placed in the combustion chamber, but away from the flame. In this context the sensor is ON when the water is being heated (and gas is being consumed).

2.4.9 seems to be working better from the start. all the switches updated immediately to the correct values. i will track them today and provide feedback

regarding your temp sensor on your water heater (which seems cool btw), what do with the data you get back: i guess you track how much time the water heater is heating, but then what? do you cut anything on or off based on this information?

My plan for the temp sensors is basic right now, cut fans (and a window ac unit) on and off using your switch feature (which is like a thermostat). Beats programming a bunch of events (or writing a script) in HS.

but i am always looking for other ideas for using the temp sensors (my hvac is already automated with an HAI RC-80 which i love)

[Michael McSharry]

I use it to track propane consumption. I would like to meter propane use, but such devices do not exist in the commercial market. For each appliance I use the appliances's rated BTU/Hr, the heat content of propane of 90,000 BTU/gallon, and the ON duration to compute utilization. For the furnance I use the ocelot/secu16 and monitor the control valve. For the dryer I use a CR3110/DS10A/W800. Since the water heater has no electrical control I used a temperature sensor initially in the chamber. The technique was changed to using a photocell as a flame sensor and a hawkeye to deliver the dusk/dawn status of the flame.

Another think about the Temperature Switch is that you can use the reverse polarity setting to achieve different effects for the limits.

[aldonc]

I have been working with the thresholds addition and think I might be able to use it for the additional logic it will provide.

One thing I realized is that the upper/lower numbers that are used to cycle the switch state on or off are the raw values of the sensor. I have a 1.5 degree Cal factor on one of my sensors and the switch value change happens without consideration of the Cal value.

I don't know that this is a problem or even needs to be changed. I just figured I would post this so if someone else ran across it, this might help them figure out what's going on a little quicker.

aldon

[Michael McSharry]

I changed the source code to use a calibrated temperature reading so the next time I do a build and post it will have this change. I did not make any changes to the switch limits for the analog inputs from the DS2450 or DS2438. They continue to operate on the raw voltage inputs