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Nov 2, 2010 9:58am
37 posts

i have installed my segmeter in my meterbox (where my circuit breakers are), and im having some trouble with the xbee comms.

i think the issue is that the meterbox is a steal enclosure which blocks the signal – i have to be within 5 meters of the meterbox to pick up the signal from the segmeter, unless i open the door to the meterbox. When the meterbox door is open, it transmits at least 20 meters – i havent tested exactly how far but 20 meters is where i want to setup my receiver, and it works.

the meterbox is on an external wall of my house, so i would like to keep the segmeter in there to protect it.

does anyone have any ideas how i could resolve this?

Nov 5, 2010 2:15am
4 posts

Hi Kayne,

A couple of thoughts – both would require an access hole being available (or provisioned) through the meter case (one small, the other a little larger):

1) Put the SEGmeter into an IP65 or IP66 rated ABS plastic enclosure, and mount it outside the meterbox. You’ll need an access hole to run both the sensor cables into the meterbox, and the DC power supply out of the meterbox (assuming your power outlet for the DC adapter is inside). You’ll probably want a rubber grommet to seal the meterbox hole from dust and moisture, and make it smooth for the cables to pass through without getting cut. The Small Box in the SEG shop is pre-drilled for 6 SEG channels, or you could also pick up a “blank” box from one of the local electronics shops (e.g. Jaycar, Altronics) and drill it yourself. 

2) Assuming the Zigbee module you currently have is a chip or wire antenna model, you could switch it out for one of the models that use a U.FL Connection, add a duck antenna and possibly a U.FL connector and run that outside of the meter housing. Here are two examples models from local suppliers ToysDownUnder and LittleBird, but various other suppliers stock them too. You’ll need to be careful to pick a module of a compatible series with the gateway you have in your SEGbox.

If the latter option seems a better choice for you, drop me a note and I’ll see if I can help you work through the logistics (organise a swap and configure the replacement node module to match your gateway). 

Nov 5, 2010 2:51am
37 posts

thanks for the info Paul!

I had thought about mounting the segmeter outside the meterbox (i have it mounted in a IP65 enclosure). I’m not sure if I am a fan of this though for a couple of reasons: the case has a clear lid and i worry what the victorian sun would do to all the components, and also the meter box is on the front external wall of my house and i dont want the segmeter drawing any unwanted attention.

The second option could be a winner though. im using series 1 Xbees, but they have the little wire antennas. do you have any series 1 xbees with external antenna connections you would want to swap? otherwise i might see if i can find one with an external antenna connection on ebay or something – i don’t want to spend too much cash on this project.

Nov 5, 2010 5:07am
4 posts

No worries :)

I know Sam did a lot of trialing and testing with various Zigbee options before settling on the 2mW Series 2.5 modules. In a number of cases, the earlier 1mW Series 1 modules didn’t seem to have quite enough guts, and sometimes will intermittently drop out.

I don’t currently have any Series 1 U.FL’s, just some wire antennas the same as you currently have. I can see some possibly cheap purchasing options, so will have a look and see what I can source. I’ll also investigate sourcing the connector and external antenna. Once I have a handle on that, we can discuss and organise a module swap and how to handle the antenna if you’re happy with that?

Nov 5, 2010 5:26am
37 posts

i had a look around and i might be able to source a WL-520gu secondhand. if i can do that i have an external antenna i can put on it. i think this would get me out of the bind I am in, and save me from needing the arduino/xbee receiver i have now.

don’t go to too much trouble with the xbees, but if you can let me know how much you can source series 1 (UFLs) for or what you want for a swap, that would be great.


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