Industrial Engineer · phase 8 of 16
Keypad / HIM
Local operator interface used to view status, edit parameters, issue commands, and read faults.
The Explain card
- Plain English
- The keypad, or human interface module, is the little panel on the front of the drive. It shows status and faults, lets you read and edit parameters, and can start, stop and set speed on its own.
- Example
- A technician pulls up the fault history on the keypad, sees three overvoltage trips at the same time each shift, and knows to look at the deceleration ramp.
- Why it matters
- The keypad is the only view into the drive with no laptop, and on many drives it also holds a copy of the parameters that can be pushed into a replacement. A drive left in keypad control ignores the PLC, which is a common reason a motor will not start.
- Hook
- The front door, and sometimes the only key.
Where it sits in the deck
Phase 8: VFD Drive Hardware and Power Path
Inside the drive: rectifier, DC bus and inverter, the three stages every variable frequency drive uses to rebuild the waveform a motor sees.
