07-27-2011 10:42 PM
Could anyone please tell me what
"Input current flow: sinking, sourcing
Output current flow: sinking"
Means???
I am very very much confused about this.
Thanks in advance.
07-27-2011 11:35 PM
Sourcing vs. sinking deals with the direction of current flow and whether the load is upstream or downstream from the DAQ device.
Look at pages 4-6. and 4-10 of the manual for wiring diagrams.
07-28-2011 04:09 AM
Dear raven
I went through the wiring circuit, but not get much from it.
What does upstream and downstream mean?
07-28-2011 08:54 AM
Direction of current flow and what part of the circuit comes first.
In a sourcing application, the power supply provides the power to the DAQ module first, which controls the the output that goes to the load. The other side of the load goes back to ground to complete the circuit. So the DAQ module is upstream of the load.
In a sinking application, the current goes from power supply to the load, then the load to DAQ module. The DAQ module then controls whether the current goes to ground or not to complete the circuit. Here the DAQ module is downstream from the load.
07-28-2011 10:41 PM
Thank you Raven for the reply.
So for a simple DAQ that takes in Proximity sensor input and outputs signal to actuators like solenoids, motors etc.
What kind of DAQ is suitable fo this kind of job?
Please reply.
07-28-2011 10:51 PM
I don't know. You'll have to look at the wiring diagram for whatever sensors you are using.
For me, a sourcing type output is the more intuitive wiring diagram because as an analog output, you are providing the power to the device (i.e. sourcing.) But a lot of electronic transistor circuits work on a "sinking" principle. The type of transistors they use would determine sourcing vs. sinking. You may have a device where it doesn't matter whether it is a sourcing or sinking output as long as you wire it correctly according to the DAQ module.
If you aren't sure what type of DAQ module to get, you need to find someone who is familiar with your application. Read the manual for the sensors and contact the manufacturer if you still have questions.
07-28-2011 11:51 PM
So in this case if i am using a product:
FESTO SMT-8-NS-K-LED-24-B as the proximity sensor.
And CPE10-M1bH-3GL-MS as the solenoid valve.
What would you suggest.
08-01-2011 11:03 PM
For the digital inputs for the proximity sensor, it looks like it just uses a reed switch of some sort. You should be able to wire that up anyway you want.
The valve appears to be a solenoid coil, you should be able to use either a sourcing or a sinking digital output. If it was me, I'd use a sourcing output because it is more logical. You may want to put a diode in reverse across the solenoid coil. This should help prevent damage to the digital output in the event of electromagnetic surges.