Wireless building control and sensors

[mramos1]

Our company owns a number of buildings. The building manager has to check fluid level, AC power, etc. in one of them all the time. On the roof and he sits on the 5th floor.

I bought a $6 rain detector from allelectronics.com, it will do what I want other than the range is 2 floors short. We are on the 5th floor, it will reach the 9th floor. It is a ten story plus the roof. Of course the items are on the roof (under cover). He wants to know when if the cooling tower water is low, a certain unit trips a breaker, via wireless to his desk.

I was going to (shhh) modidy the rain unit and try for two more floors, however, I heard about Zig-bee.

Does anyone have any personal favorite transmitter/receiver (one way is fine, a transciever would be better). A pair that is low cost and has a good range of 500-1000 feet. This rain detector said 300 feet and it does 4 floors fine. Not bad for $6 and all that concrete and steel. I will use it elsewhere.

I plan to search the forum here as I saw a link to a long range low cost zig-bee some time back, but looking for ideas.

EDIT: Sorry. I meant for this to go in design ideas. But I guess if you use zigbee, you are using a micro of some kind. I found dknguyen's link to www.maxstream.net as well.

 

[blueroomelectronics]

The XBee works great, using a couple of them for a wireless card reader.

 

[mramos1]

Bill,

I think I looked at them this morning (maxstream.com). The one I saw was 3.3vdc, other than that had a great range. They had a pro, but I do not think I will need it. Just RS232 TTL to the pic and 5vdc operation and I will be good.

I want to make a base unit to tie to his PC via RS232, and have a number of units sending data if something is wrong. I plan to use the 12F675 to do reading of the sensors and talking to the zigbee to send it to the master unit.

Are you using multiple units talking to a single master?