GS20A-CM-ENETIP / GS23-20P5 — EtherNet/IP Register Map (To_VFD / From_VFD)

Sep 8, 2026 3:16pm · 34 views
vfdethernetipautomationdirectgs23-20p5gs20aplc1c3d
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Connection type: Class 1 Implicit I/O, Exclusive Owner Output Assembly (O→T): Instance 100 (0x64), 3 words / 6 bytes Input Assembly (T→O): Instance 101 (0x65), 16 words / 32 bytes

To_VFD — Output Data (PLC → Drive)

ElementDescription
To_VFD(1)Control Word (see bit layout below)
To_VFD(2)Frequency Command — hundredths of Hz (e.g. 3000 = 30.00Hz)
To_VFD(3)Fault/Reset Word (see bit layout below)

To_VFD(1) — Control Word bits:

  • Bit 0-1: 00=No function, 01=Stop, 10=Run, 11=Jog
  • Bit 4-5: 00=No function, 01=Forward, 10=Reverse
  • Bits are edge-triggered — once set, they latch until explicitly changed (clearing Run does nothing; you must send Stop)

Common values: Stop = 1 · Run Forward = 18 · Run Reverse = 34

To_VFD(3) — Fault/Reset Word bits:

  • Bit 0: Trigger External Fault (EF)
  • Bit 1: Reset fault (clears any active fault — confirmed working on internal errors, not just EF)
  • Bit 2: External Interruption (B.B) = ON
  • Bit 5: Enable Fire Mode

Reset fault value: 2 (pulse it, then clear back to 0)

From_VFD — Input Data (Drive → PLC)

ElementDescription
From_VFD(1)Fault Code (low byte) / Warning Code (high byte) — 0 = healthy
From_VFD(2)Status Word (see bit layout below)
From_VFD(3)Frequency Command / PID Setpoint (hundredths of Hz)
From_VFD(4)Output Frequency — actual commanded Hz (hundredths of Hz)
From_VFD(5)Output Current (amps)
From_VFD(6)DC Bus Voltage
From_VFD(7)Output Voltage
From_VFD(8)Active multi-speed/PID step number
From_VFD(9)Reserved
From_VFD(10)Digital input counter value
From_VFD(11)Power factor angle (cos θ)
From_VFD(12)Output torque (%, tenths)
From_VFD(13)Actual motor speed (RPM)
From_VFD(14)Reserved
From_VFD(15)Reserved
From_VFD(16)Power output (kW)

From_VFD(2) — Status Word bits:

  • Bit 0-1: 00=Stop, 01=Decel during stop, 10=Standby, 11=Run
  • Bit 2: JOG active
  • Bit 3-4: Direction/transition state
  • Bit 8: Frequency source = comm interface
  • Bit 9: Frequency source = analog/external terminal
  • Bit 10: Command source = comm interface
  • Bit 11: Parameters locked
  • Bit 12: Running status (1 = running, including standby) — most useful bit to watch

Notes

  • Card requires proper chassis grounding (via TB1 on the card, bonded to the same ground point as the drive's main power ground) — a floating ground can cause the card to hang in a self-test/bootloader loop indefinitely.
  • Card's J2 jumper is for firmware updates only; must be removed for normal operation.
  • Tested working with Productivity Suite (P2-550) using EDS-based Exclusive Owner connection, "Include Run/Idle Header" forced on by the connection type (required, not optional).