Siemens Modbus Power Meter

I have several Siemens 9410 power meters throughout the factory. What is the best way to connect them to Control Logix PLC?

Thanks.

Does the PLC need to be involved? I'm planning to install a bunch of them and will just get Kepware to read the values off the meters and send them across to the historian.

Otherwise, gateways are an option but are usually limited to the number of devices they can interact with via modbus.

The Control Logix does have Modbus TCP instructions... they're clunky but I have a CPX reading off of one meter now successfully. I did mess up the byte order, but caught it a couple of weeks later when the consumption went past the 3rd byte.

Edit: Some power meters have an RS485 interface that you can use to interface and then the Ethernet link to get all of the data from a single connection.

I have 4 9410 "talking" to a compactlogix. I used a RTA gateway to talk to the meters via Modbus and write the values to the Compactlogix via EtherNet/IP. You setup the gateway via built in webserver. On the logix side, the values just "show up".

https://www.rtautomation.com/product/460etcmc/

Thank you so much for your feedback. I am afraid that all meters are RS-485 Modbus. Not sure how reliable the would be RTA gateway but this looks like the only option to get the data back in PLC. Once in PLC, I plan to map it to the Historian tag.

I will check again if this meter can do Modbus TCP, then Kepware can run on one of our servers and take all the data and map it to the Historian directly. I hope I understand this part correctly.

skkn said:

Not sure how reliable the would be RTA gateway

Click to expand...

The RTA gateway is not likely to be the weak link. Modbus comm reliability is subject to electrical/electronic noise sources or surges, mechanical disruption on the network bus wiring or loose connections, slave/server faults; none of which relate to Gateway performance. RTA is a reputable supplier.