MC43 C2:51 Open Load Message

Kevin 5 years ago in IQANdesign updated by Thomas Moberg (System support) 5 years ago 3

We are using HS output C2:51 DOUT G on an MC43 FS module, and we are getting open load errors displayed even though the setting 'DOUT under current detection' set to 'No'. I have downloaded the application from the system (because I wondered if the undercurrent setting hadn't been set correctly) and it was still showing 'No'.

Is this a bug or perhaps any other reason it could be causing problems? When energising the output using software we get no faults appear and the output states 'true' when measuring in IQAN Design. When we switch the output off, we get this error. We have a load of approx 100mA connected direct to ground.

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We have two different ways of detecting Open load on the DOUT.

The under current detection is only for when the output is turned on.

This is from the DOUT section in the appendix in the instruction book.

Here you can see that when the output is off we use the resistance for the open load detection.

Hi Thomas,

We have a total resistance of 235 ohms connected directly to DOUT G through to ground. Does this suggest we have an open load output off when the module detects a resistance greater than 48Kohm at 24v, ie. our system is less than that (235ohm) it shouldn't be displaying errors?


Is that resistance measured from the output to the ground of the MC43?