Hi:

I want to connect a ML 1500 wih a multimeter , I wanna automate some resistance measurements.

My multimeter has a RS 232 port and I'm connecting it to channel 1 on PLC. I can comunicate with the PLC but it send me codes I don't understand, every time I send the AWA instruction I get characters from multimeter like this( at this point my multimeter is registering 19.2 ohms):

\B9\AE\B5\A0\CF\E8\ED\8D\CF\C8

I connected my multimeter to my pc and it works with 600 baud rate with 7 bits of data size if I change data size to 8 I got weird characters.

I wonder if the PLC can interpret the characters that multimeter sends. On channel configuration I only can adjust baud rate but not the bit size.

Any suggestions?

Best regards

Gabriel

It looks like your getting HEX values from your example string of data.
Does your meter manual have a sentence reading
"Monitor, display and store data using the optional PC software"?
I did a search and that is what Extech's meter describes.
What meter are you using? Is there any software for it?

I'm using an Steren Multimeter it has a sofware but doesn't have the option you mentioned.
I think the problem is on the bit size , I connected the PLC to a Harris resistance kelvin meter with serial port and has give me better results than multimeter.

Best regards

Can you configure your multimeter to a different bit option using the software that came with the meter.
What characters did you send in the AWA command?

crsgab

have you tried with hyperterminal whatever value comes same will be reflected in plc

At first I connected the multimeter using hyperterminal but the multimeter needs whatever character to send a reading, so on the hyperterminal was not possible.
I downloaded the hercules aplication where I can configure baud rate , bit size, parity and also send characters to serial port an only on that way I got a reading on computer.
The software for the multimeter does not have an option to configure the port.

Anyway I'm using another meter and is working as I wanted.

Thanks for your help.

Gabriel