Adding ICSNet to my home system? questions.
vegastech
Posts: 369
I am running my home system on an NI-700. I am interested in getting an NXI, as I can obtain one with an NXC-ME card, which has ICSNet on the card. I am not familiar with how the NXIs work, but am I correct in assuming that they run as slaves to an NI controller? If that IS the case, can I use the ICSNet ports to power and therefore control ICSNet devices, such as the ViewStats? Thanks in advance for any tips!
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You can talk IP from your 700 to an NXI and use it as a slave. You can indeed write code for the slave that will talk ICS to thermostats on that network, i.e. Aprilaire with miniverter, and pass that data back to the master for control and display purposes. You can also take advantage of the IR, Serial, and relays for more IO. Well, O is easy, I requires more code to collect and pass incoming data over to the master. You can essentially treat it as you would an NI but for its limits. By the same effort and the same code, you could use an NI2000 or 3000 for the same purposes, with more speed and memory if that matters.
That said, I'd recommend doing Aprilaires on Serial with or without a concentrator for multiple units instead of using ICSNET and miniverters. We have found the ICSNET and miniverter to be a cause of lost connections and instability. Or use the new Color thermostats which use AXLINK, available already on your 700.
If you are just trying to use up things you already have or can grab cheaply, then yes you can, just add labor, wiring, and programming...
You change the base device number of the Axcent 3 to something other than zero and it acts just like a card cage. I have my 700 at home controlling an Axcent 3 with no issues, plus they usually sell for around $100 on Ebay.
I also agree with John about talking to the Viewstats via 422 via a serial port instead of going the miniverter ICSNet route.
I use the Aprilaire 8870s / AMX Viewstats (they're the same exact thing) in many installations and also in my own home. I agree that the mini-verters (the things that convert RS-422 to ICSNet) can be a bit troublesome. If you use the module (I've used both the Duet and standard) it's pretty easy to program.
The 8811 is a glorified Y-connector but it does keep your wire looking great and is actually not too expensive for what you get as an end result.
Multiple Thermostats can communicate on one RS422 port. However, if you've got the ports available, I'd forgo the 8811 and use the separate ports. The overall speed of feedback decreases noticeably if you go with more than one T-Stat per serial port.
Another quirk I've seen around here is HVAC guys kinda get confused about where to land the 2nd Heat (emergency heat) common belief is that it should land on W1 but the 8870s seem to want it on W2. this is, of course, for all electric heat pumps. 1-stage cool 2-stage heat.
I've included a screenshot of one of the control pages so you can kinda see what controls/displays you might want to include. In my example, secondary heat is usually done by press-n-hold on heat. Most folks around here just leave it on Auto all the time.
I've found that for shorter runs CAT5e works alright as 4 conductor for the data run to the T-Stats. On longer runs, you might want to look at something like 4-conductor with a shield/drain.
Another thing I've found that is a good idea is do not use the 24-VAC from the HVAC unit to power the T-Stats themselves. Get a separate power supply for them. HVAC power is notoriously bad and I've lost a few T-Stats for this reason. Putting them on their own power supply has eliminated any 'blowing up' issues altogether.
Here again, you HVAC person might get very confused by this.
That's true for the most part, but the ME260/64 card is DUET capable. In fact, it's the first NetLinx processor that was. It's still nothing like as fast as a x100 series integrated controller, but will still run a pretty complex and advanced system.
I would not recommend using ICSNet on the thermostats unless you absolutely must though. My standard MO with them is to hook them up to one of Aprilaire's DISTY panels as a junction point, and then hook the RS-422 out directly to the AMX controller port. They are thermostats; not like they are so chatty you have to worry much about speed, and even then, at 19200, they are more than zippy enough for normal use.