new thermostat on reptile basic

Alex-
How about this, buy one and if it does not live up to expectations I will take it back for full refund including shipping. That work?

I will be in White Plains NY this weekend if anyone wants to check them out!

I just ordered a ve 300! Can't wait to get it!! I'll let everyone know how it is. Thanks again Rich.

Quote:

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Originally Posted by Reptilebasics

I also went away from the dimming method of proportional control. I went with a duty cycle approach or “pulse”. Basically we chopped up a 1 second period into about 900 parts. We gradually increase or decrease the number of parts of a second the power stays on. The trade off is this is not too good with incandescent light bulbs for heating. They will blink.

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In theory this would not work. Zero crossing happens 120 times per second (two half cycles with a standard and inverted wave at 60hz). The component that controls the AC (Triac) can be turned on anywhere within the half cycle but can not be turned off manually. It has to wait for the voltage to drop back to zero before before it "releases". It can then be refired on the next half cycle. Pulsing the circuit more or less times makes no difference because onces its fired you are along for the ride. So the maxiumum number of time slices per second is 120 with a triac. The only exception would be if it was mosfet controlled in which the DC current can be turned on/off at will. Sorry, I had to. :D

Dion Brewington
Owner, Spyder Robotics

Yes, maximum number of opportunities to grab the zero crossing is 120 times per second. 120*8 is 960. The algorithm is using 960. Reason for that is more software guys specialty but it allowed me to not move one full "slice" per pass through the software loop. Had something to do with the speed of the clock set up for the main program loop. Made it much easier to soften the rate of change in the output duty cycle. He had it set up for less but while experimenting we found it desirable to use the larger number.

I have one of these and I love the proportional day and night built into it without adding anything to it. It was well worth the price. I have it attached to a 6 shelf rack with 15 feet of heat tape and it works great. Keeps 92 degrees in the day time and 90 int he evening. I set the day time temp to start at 0830am and the night to start at 0830pm. Also it has an alarm that sounds if it reached 5 degrees hotter or cooler than what you have it set at. And also an alarm if it has a critical error and the system shuts down. There is also a fail safe on it so if you lose power it will remember what temps and times were set so you will not have to set it again. I love it and would recommend it to anyone for a thermostat.

http://img715.imageshack.us/img715/7...statlcdbig.jpg


I have choose this one (195.00)
made by

Daniel Chochuľa

http://morel.snadno.eu/Termostaty-a-regulacia.html
you have to ask for 120volt edition, no extra fee

Measurement and control of temperature and humidity.
functions:
heating, cooling.
humidification, drying.
Timers.
Cycler. (periodic switching the set time napr.natáčanie eggs, ventilation etc.)
counting the days until the end of the incubation warning in achieving the expected number of days .
Audible alarm for loss of sensors, in decline, overruns the desired temperature or humidity.

he built many model this one 6 zones control

http://morel.snadno.eu/6thum.jpg

Quote:

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Originally Posted by floricole

http://img715.imageshack.us/img715/7...statlcdbig.jpg


I have choose this one (195.00)
made by

Daniel Chochuľa

http://morel.snadno.eu/Termostaty-a-regulacia.html
you have to ask for 120volt edition, no extra fee

Measurement and control of temperature and humidity.
functions:
heating, cooling.
humidification, drying.
Timers.
Cycler. (periodic switching the set time napr.natáčanie eggs, ventilation etc.)
counting the days until the end of the incubation warning in achieving the expected number of days .
Audible alarm for loss of sensors, in decline, overruns the desired temperature or humidity.

he built many model this one 6 zones control

http://morel.snadno.eu/6thum.jpg

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Why did you resurrect this thread? Better yet, why does anyone resurrect threads that are over 2 years old.