Inverter-VFD PG card for Interface-communication to PLC-Encoder

Inverter-VFD PG card for Interface-communication to PLC-Encoder

To integrate a Variable Frequency Drive (VFD) with a PLC and an encoder using a PG (Pulse Generator) card for interface communication, you need to consider several aspects. Here’s a guide on the general setup, common components, and the typical workflow for such an integration:

Components and Considerations

• Variable Frequency Drive (VFD):
  • The VFD controls the motor speed and torque by varying the input frequency and voltage.
  • It should have a compatible PG card slot for encoder feedback.
• PG Card (Pulse Generator Card):
  • The encoder and provides feedback to the VFD for precise speed and position control.
  • Common PG cards include models from Mitsubishi, Siemens, Yaskawa, and others, each compatible with specific VFD models.
• Encoder:
  • Provides real-time feedback on the motor’s position, speed, and direction.
  • Types include incremental and absolute encoders, with incremental being the most common for VFD applications.
• PLC (Programmable Logic Controller):
  • Acts as the central control unit for automation, processing inputs, and controlling outputs.
  • It needs to communicate with both the VFD and the encoder, often using protocols like Modbus, Profibus, Profinet, or Ethernet/IP.

Workflow for Integration

• Select Compatible Components:
  • Ensure the VFD, PG card, encoder, and PLC are compatible with each other.
• Install the PG Card in the VFD:
  • Power off the VFD before installation.
  • Follow the manufacturer’s instructions to insert the PG card into the designated slot.
• Connect the Encoder to the PG Card:
  • Use appropriate cabling to connect the encoder’s output to the PG card inputs.
  • Ensure correct wiring for connections as per the encoder and PG card specifications.
• Connect the VFD to the PLC:
  • Use the appropriate communication interface to connect the VFD to the PLC.
  • Configure the communication settings on both the PLC and the VFD to ensure proper data exchange.
• Configure the PLC:
  • Set up the PLC to read the encoder feedback from the PG card via the VFD.
  • Program the PLC to control the VFD based on the encoder feedback, implementing necessary logic for speed, position, and torque control.
• Parameter Settings in VFD:
  • The VFD parameters to accept the PG card inputs and utilize encoder feedback for control.
  • Detailed parameter settings specific to the PG card and encoder integration.

Mitsubishi FR-A700 VFD with FR-A7AP PG Card:

• Components:
  • VFD: Mitsubishi FR-A700
  • PG Card: Mitsubishi FR-A7AP
  • Encoder: Incremental Encoder
  • PLC: Mitsubishi FX or Q Series
• Installation:
  • Install the FR-A7AP PG card into the FR-A700 VFD.
  • Connect the incremental encoder to the PG card using shielded cables.
  • Connect the VFD to the PLC using RS485 for Modbus communication.
• Programming:
  • Write the PLC program to read the encoder data via the VFD and implement control logic.
  • Test the system and make necessary adjustments to ensure accurate control.