MC2 vs MC43 open load

Aderas verdes 1 year ago in Master modules / MC4x updated by Gustav Widén (System support) 1 year ago 1


Previously we used MC2 in a project. Now changed master module in the program to MC43.

We have a DIY test board (large resistors with LED for indication) to double check if the machine sends signal to valves etc.

Using COUT channels...so connectors come in pairs. With MC2 if one of the connectors wasn't connected to a load it would display "open load" error when machine would send a signal to a valve that isn' t connected, but connected one would work when output is signal is given. (no open load error when joystick is in neutral)

Now with MC43- both COUT pair connectors have to be connected for it not to display "open load" error..even when joystick is in neutral position.

Is this because MC43 diagnoses itself differently than MC2 or is there something to be changed in the program?


MC2 could only diagnose open load when the output was on, by measuring current. 

The MC4x has more diagnostics than an MC2. 

In addition to an open load detection based on measuring current, MC4x/XC4x also detect open load when the output is off. 

If the COUT channel is configured to be bidirectional in IQANdesign, the open load error is detected if any of the two loads are missing. For an application that only use a single coil, the COUT can be configured to Bidirectional=No.