MD-HMI(4x20) Input Problem

[nheilBRO]

Hi there,

Anybody could suggest on this, I set the channel1 on my MD888+ for PWM to make it 12Vdc the output and its worked fine, I'd assigned a # for this channel on the HMI for turning ON/OFF the ch#1, now I can easily turned-ON the switch with the output of 12V but I cannot turned-OFF the ch#1. but in output 1,2,3,4,5,6 with 24Vdc I can easily ON/OFF. whats wrong in my program.

In my analysis, when ch#1 becomes 12V then I cannot trigger anymore.

thnks.

[support]

Once you used the SETPWM on the output, the PWM override the ON/OFF status of the digital output and hence you can't use it as normal digital output anymore until the PLC is reset.

So you will have to use SETPWM on this output and set to zero percent duty cycle in order to turn it OFF.

[nheilBRO]

Hi Support,

OK...done.  Fantastic!!!!  

Thanks.

[nheilBRO]

hi All,

any idea.... why when an add expansion card MD-EXP1616R on my MD888+, the MD-HMI keys is not responding?

thanks in adv.

[support]

When you add an expansion board EXP1616R between the PLC and the MD-HMI, the keypad I/O position is shifted by 16 places. So now the key starts from 33 to 48. Try to scoll down your input column to reveal inputs from 33 to 48 and then press the key on the MD-HMI and it should show up on the online monitoring screen.

Do ensure that you do not hot-plug unplug the MD-HMI cable from the PLC or expansion while power is ON. This can cause damage to the IC which can also cause the MD-HMI keypad to not working anymore. Hopefully in your case it is not a hardware problem.

[nheilBRO]

thanks a lot, its working now.