Comunication with RF modems

[John]

Hi,

I have two T100MD communicating by RF modem on the port 1, but sometimes the comunication isn?t good, the PLC and the modems are on two crane bridges that always are moving, and the communications always fail when the two crane bridges are nearest.

I used one PLC in address 1 and the other in 2 and I use just use WRITEMB2 sentence in both PLC to send two register in a cusfn with 1 sencond pulse clock, what do you think is my problem and what can I do ? I would like to send you my application files to check it and help me.

Thank you

[support]

You should use the ASCII form of WRITEMB2 to communicate between two PLCs.  (i.e. WRITEMB2 to channel 3, not channel 13). There is a bug in the RTU mode of WRITEMB2 that could lead to the problems. Alternatively, use the two WRITEMODBUS statements to send the two registers and see if that would improve the performance.