Modbus Plc (koyo)

I am try to use the KOYO PLC DL250 port 2 (MODBUS) communicate with a meter reading device. The device address is stsrt from 0000h. But when I want to communicate it with the PLC I can't see the value from PC. Any body have any idea?

Is the port on the D2-250 a master or a slave?

If it's a slave, the problem is most likely in the setup of the port parameters (baud rate, parity, etc), the RTU address, or the cable. If it's a master, you have the added possibility that there is something amiss in the ladder logic you've set up to manage the communications.

Are you getting any error codes at the master?

Two other things to check with AutomationDirect.com's tech support. First, the 205 supports more commands as a slave than it does as a master, so make sure the command you are using is available. Second, the very low addresses of some Modbus devices are not accessible to the Koyo because of the way they convert addresses. Make sure the address you are reading is available.

I assume you have verified the com link is working using a PC and a terminal program or such.