Trying to connect propane tank to hai

I spoke with a guy at a propane tank monitoring company and he said that I could get a gauge that would monitor the level of the tank and send out a voltage from 1-5 volts dc. The question I have is how to read the voltage with the pannel to be able to alert me when the tank level is low. Any ideas?

One possible solution would be to interface your propane gauge to a  Beagle Bone Black device http://beagleboard.org/BLACK  and then have the device send messages to the OP2 indicating the level of propane.  You'll have to implement a simple voltage divider circuit for the device since your output is 0 to 5 VDC and the Beagle Bone device max input is 1.8 VDC.  That is, the divider circuit reduces the max input voltage from 5 to 1.8 VDC for the device.  You can then install Leviton/HAI's SDK on the device which will allow you to send messages directly to the OP2.

Sounds complicated.  An adjustable comparator relay board would probably work.

az1324 said:

Sounds complicated.  An adjustable comparator relay board would probably work.

Click to expand...

Still too complicated. I can solve this puzzle with no parts.
 
Actually zones can read voltage directly.  It may take some trial and error, but if you set a zone to a setting like a temp sensor (NOT an extended temp sensor) you will get a temperature reading based on the voltage.  The trick will be to determine which temp. translates into which voltage.  You should be able to get a resolution down to about 0.1 Volt, which should work.  Once you figure out the temp you need, just do a test of the temp. is higher or lower than that.

I remember reading in another thread from an HAI employee that it wasn't recommended to use a zone as an analog input.

The HAI knowledgeBase article indicates that the zone inputs are digital not analog. http://kb.homeauto.com/default.asp?id=551&Lang=1&SID=
 
This is also evident in the Omni Link II protocol document where input temperatures are mapped from 0 to 255.  0 being -40 F to 255 being  189.5 F.
 
 
PM me if you should need a copy of the Omni Protocol II document.
 
 
 

Newer sensors are digital but older ones were not.
 
If you haven't discovered it already, each zone is a volt meter. When you use a EOL resistor, the zone is measuring the voltage across that zone to determine if the zone is faulted or open or closed.  If you look in PC Access you see a number representation for each zone from 0 to 255. THAT is the voltage it is seeing across the zone terminals. 
 
HAI certainly wouldn't recommend using the zones to measure voltage, but guess what, they do it with their temp sensors. In fact their older temp sensor is nothing more than a temp to voltage sensor.  Take a volt meter and measure from ground to sensor output and you will see a voltage representing the temperature. Its not rocket science. Zones are also pretty protected against surges and such because long wires can experience these things.  If you are careful and don't exceed 5 V in a zone, you shouldn't hurt it.
 

BobS0327 said:

This is also evident in the Omni Link II protocol document where input temperatures are mapped from 0 to 255.  0 being -40 F to 255 being  189.5 F.
 
 
PM me if you should need a copy of the Omni Protocol II document.

Click to expand...

 
The fact that HAI tells you the temp conversion for 0 to 255 certainly does NOT indicate that the signals are digital. In fact, just the opposite. the analog-to-digital converts HAI uses on each zone are 8-bit, producing a number from 0 to 255, just like in PC Access, you see values for each zone from 0 to 255.  I believe it uses a 12V reference where a 1 = 12/255  = 0.047 volts, 2 = 2*(12/255) = 0.094 volts, 3 =  3*(12/255) = 0.141 volts, etc
 
So to test for 3V, your number is 64, then check the docs to see what "temperature" 64 is.

 
 

So based on Ano's kind response above, it seems that if you use my Analog to Digital Sensors How-To, connect the gauge directly to a zone without the EOL resistor, you should be able to figure out a 'bit' to 'level' calculation.
 
Just make sure the voltage doesn't exceed the recommendations for the HAI unit.  If you post the manual or look up the level to voltage conversion given by the manufacturer of that gauge, we could help some more.

Not what you are looking for but at least someone else is also thinking about this:

http://www.wink.com/products/quirkyge-refuel-propane-tank-gauge/

I'm pretty sure he means a much larger tank.

swaggy said:

Not what you are looking for but at least someone else is also thinking about this:

http://www.wink.com/products/quirkyge-refuel-propane-tank-gauge/

Click to expand...

Well, maybe a real tank monitor such as the tank utility http://postscapes.com/wifi-propane-remote-monitoring-tank-utility to be used with the Wink hub.  This product is now on the market retailing for about $189.00.  It's designed for the future of home automation since it uses an open RESTful API as does the Wink hub.
 
BTW, Leviton has partnered with Wink to initially make Wink certified switches and eventually other items for the Wink product line.

To play debbie downer here, hope you plan on treating the install as a hazardous classified location for the sensor, cabling and installation itself. A bad installation here can lead to a worse result.