X20CM8323 NonDocumented behavior with control of elektromagnetic devices like relais etc

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1

A do have a few questions about this module, but at first some explanation about the working principle :

The X20CM8323 module is developed for controlling elektromagnetic loads in relais and liquid valves. The idea is that the current in a coil is dependent on its already developed magnetic field force. The higher magnetic field force, the higher the current. While using magnetic force for movement, the current drops and or current increase changes.
The CM8323 does both 1/ and supply current to the coil 2/ and measure the current. Even better, for each current pulse on the valve, a current-time curve of 126 values is recorded.

Now the questions - about the configuration and behavior:
1 / The time step of the 126 values can be set in the energizing timebase 100 / 1000 microseconds
2 / The full energizing time can be set 0-255 , these should be the amount of steps, with length as defined before
3/ Duty cycle 50-100%

What 1 see is
1/ with the timebase of 100 microseconds, the amount of steps dived by 5, is the full power amount, the higher are pulsed with the defined pwm. So in the PWM - modus, the maximum are 50 x 1/10 milliseconds full power, later there is only PWM. THE figure of 50 maximum is to low.
This is nowhere documented, who has experience with this ?.

2/ Changing from 100 till 1000 microseconds at first does not change the recorded curve, what is not expected and not documented.
After a 5-10 seconds running the X20CM8323 in de pulsemodus, the PLC gets a time overflow in taskclass 1 and stops. The behavoir is easyly reproducable. Anyone has any ideas ?

The evironment
1 The IO-variables are run in taskclass 1, 1 millisecond.
2 The software to wrtite the outputs ans the software to rad the current, is both run in a 1 millisecond taskclass.
3 The module is placed behing an X20BC0083 powerlink buscontroller
4 The system tick is 500 microsecond , taskclass 1 period is 1 millisecond, as is the powerlink period.
5 Systemtimer is CPUtimer, not X20/PWL interface
6 Processor a 5PPCP-US15_02 on a PP500, performance similar as the CP1586

3

Hi, it looks like the community cannot help you. Please get in contact with local B&R support.

4

Hi Jaroslav, probably this is the way to go. It was also a test for my on this community, how much information is shared here. I found a way to deal with the behavior of the CM8323. It is still very flexible, and can handle fairly large inductive opened valves. The PWM saves a lot of energy and thus prevents heating up the valves. And probably it is going to show when valves are close to stop opening. The tests are still running, the live time of the physical parts is far beyond official specifications.

Thanks for your support

Wilko Pels

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5

I hope that this will not deter you from using the community. You can not only ask for help; you can also help others, as any active experienced user is always welcome :slight_smile: