The 3AXD50000956647: Normal-use output (Pn 1.1 kW, In 6.9 A) is the continuous rating for typical fan and pump curves. Heavy-duty use (PhD 0.75 kW, IhD 4.5 A) applies when the load demands higher peak torque or a constant-torque profile — a positive-displacement pump or a small conveyor, for example. Light-overload use (PlD 1.1 kW, IlD 6.6 A) sits between the two; the 6.6 A figure is slightly below the normal-use 6.9 A, so for a straight fan load the normal-use number is the one to size against.
Fieldbus and I/O
BACnet is the onboard protocol — no option card needed. That makes this drive a direct fit for building-automation networks where the BMS talks BACnet MS/TP or BACnet/IP. Two analog inputs and one analog output handle duct static-pressure transducers or valve feedback; the 4 digital inputs and 2 digital outputs cover start/stop, fault reset, and run-status handshakes. No industrial Ethernet interface on this variant (0 hardware interfaces for Industrial Ethernet), so if the plant standard is PROFINET or EtherNet/IP, this isn't the drop. The drive communicates over BACnet only.
