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Current Out Channel (COUT) Feedback

Steven Park 2 years ago in IQANdesign updated by Jacob Meng 4 months ago 5

Hi,

I am fairly new to IQANDesign. I am using MC43 to control some hydraulic valves and COUT is used to control one of the Prop coils. I would like to get feedback on the output channel to make sure it is reaching the target output. For example, if the output is set to  500mA, I would like to read the feedback that shows the current level at the moment. Is there a way to access the feedback without using another input channel?

+1

Hi Stephen, you can use an Internal Channel to read the Current.  You can also display the current on the screen (if using one).

You can setup a Measure Channel to display what the output is.

Here are some tutorials that perhaps can help.

https://www.youtube.com/playlist?list=PLml3JrpqoJ1XgLbk29C-8Nfjc-BcEh2tN


+1

The value you see on the COUT channel in IQANdesign is the commanded current. The current regulator of the COUT is very fast, so this will quickly be very close to the actual current. 

If you command the COUT with a current that is higher than what is physically possible to drive through the load, the COUT will indicate this with the status saturated. 

On a similar note, I would like to be able to log the voltage at a particular current output to verify that the resistance of the coil is correct. Is there any way to do this internal to the MC43 without hooking up wires from the current output to a voltage input?

Jacob,

The value you can measure on the COUT in IQANdesign is the commanded current. What you also have available is the status of the COUT, e.g. open load, overload and satuation.  

By measuring the MDGN channel +BAT, you can also see the voltage the module is supplied with. The voltage at the COUT highside relative to ground will be slightly lower than this.

Since you want to check the coil resistance, it sounds as if you are perhaps making a hydraulics test bench and want to check if 12 or 24V coils are fitted? Then maybe you could experiment with running the COUT to saturation?  

Hi Gustav,

It is a hydraulics testbench. The design engineer not only wants to verify that the correct coil is installed but also that the coil is built to the required resistance. We need to verify that at a certain current, the voltage is between 23.8 and 25.2 V.

Since V=IR, and the resistance is basically static, can the current be regulated without varying the COUT voltage? Is COUT voltage always static at just below the power supply voltage? I an not an EE but I am trying to understand how to accomplish this without additional connections or an additional volt meter. 


If I set my current limits strategically based on I=V/R, is that how I could trigger the open load, overload, or saturation statuses?