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What Modbus register is best to use when measuring currents in an S811+?

When monitoring 3 phase currents in an S811+ from a Modbus network, Eaton recommends that Modbus data addresses 341-343 be used rather than 337-339. These addresses are scaled values (x 0.1) and will provide improved resolution.

For example, if a motor current is 1.7 amps, the value(s) returned from addresses 341-343 will be 17 which can be divided by 10 to result in a 1.7 amp measurement.

By contrast, if addresses 337-339 are used, the return will be 1.