Why must a PWM output be wired as shown below in the XA2 manual?

When I've worked with mobile style PLC's in the past: It's just 1 pin for an output that delivers a PWM signal to a solenoid, then the other pole of the solenoid is wired to a common ground.

Why must there be three pins involved for this? Why shouldn't you wire one pole of the solenoids to a common ground (same potential as battery negative)?

Thanks in advance.

Dear reader,

I need for an aplication a proportional  9 Volt output. is this possible with the system running on 24 Volts? Because if i would use a COUT the voltage would be 24 V.

Is it maby possible to use a PWM output? 

if so, how do i use PWM?

Another option is to run the system on 9V, is this stable to use?

Dear reader

we need for an aplication 4 Voltage inputs on one of the MC4x serie, those voltage inputs aren't a problem but we need to have voltage inputs for 0-7 Volts. is it possible to connect those sesors on the voltage in for 0-5 Volts ,0-5 Volts will do the job in our program. this 7 Volts on the input isn't continuous, these are just peaks.

Thanks for the help!

We have a customer that is experiencing graphical errors with an MD4. S/N 1535280044. Customer is complaining that the display sometimes is black, sometimes white and sometimes multicoloured lines:

Does anyone know why this could be happening? It appears to be happening sometimes at startup, but also when machine is running (randomly dropping out). Im not sure if its the hardware issue that was changed a couple of years ago on the MD4?

I would like to define a common remote connectivity solution that works across MDL2 and MD4 machines. 

Will G3 work on both?

I can open up an MDL2 application file in IQAN Design 5.03,  add a G2/G3 modem, connect them both to a diagnostic bus and save the file.  

Will IQAN connect work properly ?

I have encountered a problem with DOUT on XA2 modules. We operate several Parker D1VW (NG6) valve, with multiple XA2 modules. Some DOUT (from different XA2) does not activate the magnet coil, although it looks completely correct when I'm connected to IQAN Design . DOUT = Tru.

We use valve contacts with zener diodes, it works on most DOUT otherwise. I had to change the output to PWM instead and then it works without a problem. Is there any problem with the XA2 modules, or are the Zener diodes that do not work against XA2?

Due to a voltage drop in the system, because of an electric fan switching on, all the voltage inputs give a low error.

The strange thing is that the voltage drop is not so big. it drops from 27 to 22 for only a sec due to the high start current of the fan.

Is this normal, I thought the modules could be used in 12 VDC system also. So the voltage drop should not be a problem.

regards,

Ed

I was told some months ago, the the MD3 would be obsoleted sooner rather than later, but I have not seen anything further on this.

Any idea how far out is the timeline on obsoleting the MD3?

I am using an IFM Efector 4-20mA 2 wire sensor on the MC41 inputs capable of sensing current.  Their hookup diagram is what I expected connecting one side of the sensor to high and one side to the sensor port.  The input shows a high error when I'm in a neutral state and I can confirm with an ammeter in line that I am sending 4mA to the controller.  My best guess is there is too much impedance and internally it is not correcting for it so I tried adding a 5k resistor to ground externally to split the current.  It now senses 3.8mA but is no longer accurate over the range.  

When the G11 Bluetooth Modem was still in BETA one major limitation was that you could not flash a password protected project.  

Has the limitation been resolved?