Control 2 tanks?

[romebaby]

Can I control 2 tanks, 50ft apart, with 1 controller? What else would I need for the 2nd tank besides a relay box, temp & ph probes?

[rimai]

You will need to extend the svga cable for the relay box to get that far.

[00Warpig00]

I'm planning to eventually control three tanks. my 180G DT and two QT tanks a 20GH and a 29G

plug your expansion relay module (that the usb cable plugs into) and then use a couple of these

http://www.amazon.com/gp/product/B004EE ... UTF8&psc=1

to create a custom length "SVGA cable" out of a couple of cat5 cables

Nick

[mvwise]

I currently have my RA+ controlling my main tank, but will be adding a frag tank that is on the same wall but about 15 feet from the head unit location.

I would like to have an relay expansion module, temperature probe and ph probe on the frag tank. The expansion hub is located in the stand of my main display.

Am I correct in assuming I would need to run a USB cable from the expansion hub to the relay expansion, another for the ph module and an extended temperature probe for this to work or am I missing something?

How long can I run the temperature probe? Would the 10ft probe with a 6ft extension work or is this too far?

Is it possible to have two expansion hubs on the same system, so that one is located in the frag tank stand and connects to the other in the display tank stand? Then the relay expansion and ph module could connect to the second expansion hub, cutting down the number of USB cables spanning the gap and also leaving the door open for future expansion on the frag tank side.

All thoughts are welcome.

Thanks.

Sent from my iPad using Tapatalk HD

[rimai]

I think it is too far.

[enigma32]

+1 rimai.

I2C (which I believe the ph, relay, and expansion hub use) really doesn't work past 1-3 meters based on everything I've ever heard (and I think really anything over a couple feet is a stretch, depending on bus speed). In your case, you might be able to get it to function, but I can't imagine it would be very reliable.
1wire (temperature probe) buses can be pretty long, but it depends on a number of factors. (I can't post links, but if you do a google search for "1wire bus length" and click on the first link from Maxim there's a very detailed document about 1wire)

You could do some custom work involving your own RS-485 or CAN bus or something like that; but it would be pretty involved depending on your level of experience.

Probably much easier to use a separate controller