Mettler Toledo Safeline RS422 communication

Hi everyone!

I'm trying to set up a communication between s7-1200 and Mettler toledo safeline. I'm sending a service request(request pack count) to the metal detector, no answer. But when i leave the receive line open, and there is an event then i receive event data. I'm not sure what i'm missing here. Is there anyone who has successfully written a program for RS422 communication?
Questions:
Do i need to add external termination to the network?(sofar i've seen no info on this)
The metal detector should answer, when requested or do i have to acknolwledge the event first?

i have high and low lefel protocol manuals and everything seems to be correct but for some reason there is no answer.
I'll attach some screenshots with the data i've got.

Thanks for all your help.

http://www.genemco.com/catalog/pdf/KPSB279safelinemanual.pdf

If you are getting some information in/out then I would start to look at the timing of your communication.
Are you receiving an ACK signal after you send the command?

gclshortt said:

http://www.genemco.com/catalog/pdf/KPSB279safelinemanual.pdf

If you are getting some information in/out then I would start to look at the timing of your communication.
Are you receiving an ACK signal after you send the command?

Click to expand...

Thanks for your answer.

I am not receiveing an ack signal after sending a request.
The manual you've posted only describes rs232 comms and not rs422. As i'm receiving data it seems that there is something wrong with my request or with the network on transmit line. I've tried both comms on the metal detector (direct and network). I'll post my port configuration as well.
I can upload the manuals i've got if someone has time to help me out.
Thanks!

Metal detector type: Profile Advantage, Head type: rectangular. Version: F48.1.0.r2