Australia Posted 21 Oct 2011 I don't know if you had any achievement with this Greg, but I have an exceedingly similiar problem. My setup is: M340 connected to Connexium Ethernet Switch linked to EGX100 Gateway related via modbus serial Sepam Safety relay. I have prepared the ST in unity http://modiconm34020739.frewwebs.com/13939681/modicon-m340-no-further-a-mystery