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SERIAL CONNECTION BETWEEN PM5100 series and A9MEM3150
Metering & Power Quality
Schneider Electric support forum about Power Meters (ION, PowerTag, PowerLogic) and Power Quality from design, implementation to troubleshooting and more.
Both meters support Modbus RTU over RS-485 link. Both support the same baud rates and same parity (even odd none). The question about how many can be connected is an ambiguous question. A lot depends on how the devices will be used.
A system with devices being polled once every 15 minutes with an acceptable delay of 15 seconds could support a lot more devices than a system polling devices every 5 seconds with 3 second delay maximum. (Assuming both devices support polling this fast).
Again the maximum quantity is not an answer I can give because there are different factors. There are limits based on distances between devices for different baud rates. There are limited based on how much traffic is expected on the serial line. There are limits based on the modbus protocol itself. Then there is also limits based on what the gateway (or Modbus Master device) can handle in turns of burden. All of these factors and others come together to make a limit based on what is needed from the system.