communicate two powermeters with ac-500-eCo via modbus RTU.
What error code do you have?
Please ensure you have a cyclic EN inputs of the COM_MOD_MAST blocks.
When I read more that 1 slave, I insert two COM_MOD_MAST blocks, each one fixed for own slave. I'm not quite sure if the logic for switching of the slave address (as in your example) will work correctly.
Then the EN of the COM_MOD_MAST blocks should be something like that:
COM_MOD_MAST1.EN:=COM_MOD_MAST2.DONE OR Ton_1.Q
Ton_1.IN:=(NOT COM_MOD_MAST.DONE) AND (NOT Ton_1.Q) with time about 15 s
Timer for the first EN will generate EN pulse at initialization of the program or in case the communication lost