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How do I troubleshoot an Altivar Process Drive that would not connect when trying to communicate with a Modbus over Ethernet (Modbus TCP) network?

Issue:
Altivar Process Drive twould not connect when communicating with a Embedded Modbus Ethernet network?

Product Line:
Altivar Process Drives (ATV630, ATV930, ATV650, ATV950, ATV660, ATV960, ATV680, ATV980)

Environment:
All serial numbers for Altivar Process Drives

Cause:
N/A

Resolution:
Note: This FAQ goes over some basic checks and troubleshooting tips. For extended troubleshooting please refer to your drives Embedded Modbus Ethernet manual that is attached at this FAQ.

Drive Will Not Connect

Installation
- Make sure proper Ethernet cable is connected to the appropriate Ethernet serial port. Altivar 900 Drives have 2 Ethernet ports
- Pin Layouts - Make sure we are using proper pin-outs
  - FA315321 - Where can I get the cable pinouts for the Modbus TCP connector for the Altivar Process Drive?
- Check for electrical interferences. Isolate cables
  - Use conduits or other isolating materials
  - Separate control and power connections
- Add terminating resistors if the drive is at the end or the last of device in the network.
Network
- No Duplicate IP addresses
- Make sure Modbus Address is correctly set
  - Modbus Address should match PLC's Unit ID. Typically this is set to 1 if you are writing and reading to and from the 4x registers directly
  - If you are using the IO scanner or COM scanner use a Unit ID of 255 and set drive's Modbus Address to 0
  - To configure IO Scanner Input/Output Table
    - FA294735:How do I access the Com Scanner Input and Output tables on the Altivar Process Drive?
Programming
- Make sure all Basics Settings are configured correctly in the drive and that the drive is properly Powercycled after all settings are made
  - Configure Modbus Settings
    - [Communication] [Comm parameters] [Modbus SL] [Modbus Fieldbus]
  - Configure Ethernet Settings
    - [Communication] [Comm parameters] [Embd Eth Config]

Drive Connects but Will Not Run on a Command

Checking the Network
- If you cannot write to the drive, first verify you can read from the drive. If unable to read from the drive then re-verify the drive is connect properly to the Modbus Ethernet network
- Verify that you are reading the proper input and output addresses
  - Altivar 600 Communication Registers
  - Altivar 900 Communication Registers
- Check for possible register offsets
Checking the Drive
- Confirm that the drive is properly to receive commands from the Network
- Check Command and Reference Menu
  - [Complete settings] [Command and Reference]
- CheckControl Mode
  - Are we using IO Profile or DriveCom (Separate or Not Separate)
- Check drive for any faults
  - Check top left corner of the keypad.
Addtional Troubleshooting Tips:
- When writing to the drive and the drive still does not respond or has an "RDY" status on he top left corner of the screen, check the Communication Map
  - [Display] [Communication map] and check the following:
    - Check Command Channel (Should say Embedded Ethernet)
    - Command Register (Should be a HEX 1 value)
    - Ref Freq Channel
    - Ref Freq
- Check LED's
  - FA316257: How can I troubleshoot the LEDs for the Altivar Process Drive when I am trying to communicate to it over Modbus TCP network?