CAI boards use a TON of electricity compared to what some other boards do in deep sleep. You don't need a cellular internet plan just a prepaid card that can send a text message when an alert condition happens or periodically. Antennas are more practical than 10KM of wire & fiber. But if you are not looking for the most efficient and cost-effective system then do what you are comfortable with.
Your suggestions on a special project.
- Thread starter BTCAD
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Okay.
Yeah I understand your point, but cellular prepaid card can only give text msg.
What I want it's a real time vacuum display of all of my sensors. I know that is a huge job to run kms of wire in the forest, but it's the only way I found for cos-effective system and real time displaying.
More ideas?
Thank you all for your replys
Yeah I understand your point, but cellular prepaid card can only give text msg.
What I want it's a real time vacuum display of all of my sensors. I know that is a huge job to run kms of wire in the forest, but it's the only way I found for cos-effective system and real time displaying.
More ideas?
Thank you all for your replys
apostolakisl
Senior Member
az1324 said:
True, but pretty much no matter what, you will need a real power source. For $50 you can get a nice 5 watt solar panel and a 7ah lead acid battery. So I don't see the point in trying to save power and giving up the point of the project. .. real time monitoring.
Yes, but there are systems in sleep mode that use a few micro-watts. You only have to send a message when the status changes between one of your 3 states.
http://www.digi.com/products/wireless-wired-embedded-solutions/zigbee-rf-modules/point-multipoint-rfmodules/xtend-module
http://www.digi.com/products/wireless-wired-embedded-solutions/zigbee-rf-modules/point-multipoint-rfmodules/xtend-module
apostolakisl
Senior Member
.05 amps out of a $10 7amp hour battery means you get 5 or 6 days of reserve power, and that is if cai uses 12v, but it actually uses 9v, so you'll probably get more. The battery should do fine at cold temps, but if this is an issue you can use a $100 battery instead of a $10 battery that would also give you a couple months of power without recharging. Batteries work fine in the cold, you lose some cold cranking amps, but at trickle levels it won't make much difference. So if you got snow on your solar panel, it would certainly melt or slide off at some point prior to the battery going dead.
I just look at your situation and I see, what, 30,000 feet of cabling?. This would be very expensive and labor intensive to run. Are you going to bury it? Are you going to run it in conduit? Animals like to eat insulation and if it is exposed to sunlight you have to worry about the insulation falling apart with UV damage. Unless you spend the money to run all of that wire in conduit, my suspicion is that you are going to have significantly more maintenance issues with wire than solar/battery.
I just look at your situation and I see, what, 30,000 feet of cabling?. This would be very expensive and labor intensive to run. Are you going to bury it? Are you going to run it in conduit? Animals like to eat insulation and if it is exposed to sunlight you have to worry about the insulation falling apart with UV damage. Unless you spend the money to run all of that wire in conduit, my suspicion is that you are going to have significantly more maintenance issues with wire than solar/battery.
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apostolakisl
Senior Member
I just googled wifi router power consumption and the first thing I came across was 18 watts for a standard dual antenna model. That is going to kill the electricity budget if you try to go with solar. You would need like a 100 watt panel and a pretty descent sized battery to keep that up and running. Of course it may be possible to turn the antenna off when not in use using CAI code to control that.
Cellular would be the best low power option, but as you mentioned, that might kill the money budget.
Cellular would be the best low power option, but as you mentioned, that might kill the money budget.
Those radios I linked have a 30 mile range so you should be able to get 1km out of them in the forest. You only power them up when you have to transmit something which is when the reading changes. That means they are off 99.99% of the time. Then you use a board that can sleep using only micro watts. It wakes up every so often to check the sensor and decide if it needs to transmit. A decent size battery will last a long time.
