Interfacing other Temperature Sensors

Hi Guys,

I'm looking to install a C-Bus system into a new house that has underfloor heating that I want to monitor with some other types of sensors (Dallas 1-Wire Sensors), but I'd like to be able to interface these to the C-Bus system such that they appear to the system as normal C-Bus Remote Temperature Sensors.

I was wondering if I could interface these sensors via the RS232 port on the PAC module or maybe via the C-Gate API's.

Is there a way that this level of integration can be achieved using any of the standard C-Bus interfaces or programming APIs?

Regards

Alex Shepherd

 

Temperature Sensors

Have you looked at the General Input unit? There are a few posts in the Forum covering this topic, and a GI programming guide on the CIS Technical website... http://www2.clipsal.com/cis/technic...2/cbus_control_and_management_system/advanced

 

These sensors are already on digital network already so the GI is not really suitable for me.

I was hoping to find a way to feed this digital signal into the C-Bus system somehow so I can use the nice little thermostats.

Alex

 

You could try an RS232 to Dallas 1 wire adapter (see http://www.techbits.com.au/catalog/index.php?main_page=product_info&cPath=10_6&products_id=29 ) and go through a PAC Controller.

 

Actually, that is exactly what I was intending to do.

The issue I have is in trying to inject messages onto the C-Bus network so that other Thermostat modules could be configured to use and act on these messages like any other Remote Temperature Sensor.

So far there does not seem to be any supported way I can see in the PAC or CTouch modules or in the C-Gate API to write the appropriate Remote Temperature Message.

It seems you can read them but not write them.

Regards

Alex Shepherd

 

cBus to Dallas/Maxim 1-Wire interfacing

Reply is a little late but may be of interest...

I have successfully interfaced a PAC to Dallas 1-Wire. I did it a while back and am resurrecting it (now that my self-build project is complete.)

I previously had the PAC polling the 1-wire bus, via a DS9097U and receiving temperature readings from a few DS18S20s / DS18B20s. I also had it interfacing with a DS2408 8 ch addressable switch as a means of bit-banging to a custom PIC-based board. The board is not needed for PAC to talk 1-Wire.

The temperature readings are easily scaled and linked to the cBus. E.g.

SetCBusLevel("Net", "Heating", HEATING_ACTUAL + intZone - 1, intTemp, "0s");

Anyway, I'm resurrecting the project and have the DS18S20s up and running again. I'll be using the PAC to access a number of temp sensors and a weather station.

Steve

 

Hi Steve et all,

You might also want to look at the new C-Bus 5104DTSI Digital Temperature Module Dallas 1 wire temp input unit.

I have a client who interfaced some third party sensors to this unit without issue. Firmware is for temperature only though (currently).

Regards,

Brad

 

what are the other plans

 

I was just referring to the earlier post where NickD said it was technically possible to attach other types of 1 wire sensors, but the firmware didn't allow it. Conformist said 'A further announcement will be made once product is available for purchase', I just took this to be a future 'watch this space'

I have always been very reasonable in my expectations so, as long as it supports the following sensors in near future, I'll be completely happy

• A humidity sensor to turn on exhaust fans in bathrooms would be a useful addition.

• A Pool/Spa/Pool Solar temp sensor in the PVC / barb sort of configuration.

• Moisture(rain), Soil Moisture & Leaf Wetness sensors for irrigation and closing external shutters/louvres etc.

• Wind Vane & Anemometer to withdraw external blinds.

• UV / light sensor to withdraw inside blinds etc.

I did restrain myself as I thought that a radiation sensor was just going a bit far for the normal home project.

Now all I have to do is either sell the idea to Clipsal Product Dev. or find someone to hack the firmware................ I see I've been daydreaming again!!

Brad

 

1-Wire

Hi Brad,

Given the hardware I'm happy to develop further 1-wire device handling for the PAC. They're generally pretty straight-forward to talk to. I have one of the basic weather stations that i'll be plugging in the the not too distant future. I've reliably interfaced to it from a PC but not the PAC yet. Also happy to share the code if it's of interest.

I've got my temp sensors all up and running on the PAC and now available on the Wiser for viewing on my iPhone etc. (via the barely fit for purpose Wiser app.)

Cheers - Steve

 

Hi Steve,

Thanks for the code offer. Always happy to get new logic/code (and think everyone here does also) so post it back when you get a chance.

Are you talking about the Thermostat widget? I know many have asked for a cut down temp widget but it hasn't happened yet.

You probably do this workaround already but in case you don't, I just use systemIOs in a method not too dissimilar from NickD's post. It gives an output like the JPG below. (in case you're wondering, dead thermistors need replacing hence the -ve temps - always die at the end of summer when they get cold due oxide creep/ moisture incursion)

I have also recently started displaying these as a 'Marquee' style display where you can have several related temps (eg all the Pool temps) going past in one widget saving some screen space and scrolling.

So look forward to your offered logic/program.

Brad

 

1-Wire

Hi Brad,

No, I've not used the temperature widget. After not immediately seeing how I could display the cBus group levels I had set (from the PAC) I just dropped a few user system IO real number widgets and populated them using a bit of code on the Wiser (based on change.)

There are seven sensors and a couple of calculated stats (associated with a heat recovery ventilation unit.) The appearance is pretty much the same as your screenshot. Using a more widget that take up even more space would not work well for a large number of sensors. I might just move to displaying a few IO strings so I can group the related temperatures rather then using one widget per temperature - I'll have to see what it looks like.

I'll post some code as and when anyone wants it, as it is still being developed and tidied up. I have used the Delay command extensively to implement the correct timing required for the 1-Wire interfacing but Delay can't be used outside of Modules. This results in having a lot of repeated code, where it would be normal to pull out the repeated code into Functions or Procedures. So I'd like to see whether I can find an alternative that doesn't screw up the timing (and is not sensitive to the PAC it is running on.)

Regs
Steve