General Input/Auxiliary Input and 240Vac

I study Smart Home Tech. at Uni and have to provide solution for a project. I decided to follow C-bus tech, however, I do not understand difference between general and auxiliary input units. Can I connect 240V ac sensor (water level sensor to measure lake level) to the C-bus? If so, should I connect it to the general or auxiliary input? I was reading specification many times but still do not understand it.

 

Thanks for fast replay. I was thinking about something like this :
http://www.rapidonline.com/sku/Elec...quid-level-sensor-fuel-and-oils/75150/61-1362
Specification says 240V ac. So can I connect it somehow? My another idea was to use 2 electrods (plates) but similary I don't know how I could connect it to the bus.

 

That sensor is basically a simple switch.

It's specs say that it's contacts are RATED at UP TO 1A @ 240v AC.

That doesn't mean that it requires that to operate, it can simply switch up to that in and out of the circuit.

Connecting to a GIU, AIU, or bus coupler would be fine, as you're simply opening and closing the circuit, with negligible current or volts involved.

 

I have one more question to be sure that understood correctly. I found ultrasonic analog sensor here: http://www.deeterelectronicsinc.com/usa_rps-401a-426a.htm
In that case assuming that values send by sensor will differ depends on water level I have to use general input unit. Am I right? The sensor operates on input voltage 20 - 30 VDC
so do I need provide additional voltage to the sensor or by connecting it to the GUI I will automatically provide the C-bus 24Vdc? Wouldn't be enough to connect it to the bus coupler?
Still have a little mess with it.

 

It looks like those sensors have both 4-20mA and 0-10V outputs. By connecting these to a General Input Module you'll have lots of flexibility.

The General Input Unit itself requires 24V to operate, so you could share the 24V supply with the sensors, saving you the cost and complexity of a second power source.

The General Input unit will not automatically provide power to the sensor, you'll need to run power to the sensor yourself. The General Input unit has a 24Vdc output connection for just such a purpose.

If you're using these sensors to measure water level, a bus coupler is not suitable for a few reasons:
- The bus coupler inputs are not isolated, so the isolation of the whole C-Bus network would be compromised
- The bus coupler inputs are only on/off inputs and cannot detect analogue values
- The bus coupler cannot provide any power to the sensor

 

Thank you very much. Now I catch it.

 

Have a look at this link at Anadex Labs. It explains how to connect a 4-20mA sensor to the C-Bus General Input Module. http://www.anadexlabs.com.au/CbusAn420.htm

Regards,
Bill