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  Drives Service & Support > 20-COMM-I > Diagnostic LED's

This page will help you learn and identify the different LED readouts available for the 20-COMM-I


#
Status Indicator
Description
1
CC
Cable Check
2
RD
Remote Bus Disable
3
TR
Transmit / Receive
4
BA
Bus Active
5
UL
Bus Voltage

Note:The UL indicator is not viewable when the drive cover is installed or closed.
Note: Interbus compliance requires different LED functions than what is normally displayed on the front of the drive (Port, Mod, Net A and Net B Leds). LED labels are provided with the adapter for application to the drive cover.

Cable Check (CC) Status Indicator
Status Cause Corrective Action
Off Master is reset or no cable connection.
  • Connect the adapter to the network using an Interbus cable.
  • Verify master not in reset.
Solid Green Cable connection good.

No Action Required

Remote Bus Disable (RD) Status Indicator
Status Cause Corrective Action
Off Outgoing remote bus is not
switched off.

No action.
Solid Red Outgoing remote bus is
switched off.

Read configuration or start data transmission.
Master may have to be reset first.

Transmit/Receive (TR) Status Indicator
Status Cause Corrective Action
Off No PCP connection is
carried out.

Verify that master is sending PCP messages.
Solid Green A PCP connection is being carried out. Flashes when a new PCP frame has been received.

No action.

Bus Active (BA) Status Indicator
Status Cause Corrective Action
Off Bus not active. Set master to start data transmission.
Solid Green Bus active, exchanging data. No action.
Flashing Green Bus active, but no data exchange. Set master to start data transmission.

Bus Voltage (UL) Status Indicator(1)
Status Cause Corrective Action
Off Bus voltage is not OK.
  • Securely connect the adapter to the drive using the Internal interface cable.
  • Apply power to the drive.
Solid Green Bus active. No action.

(1) Only visible when drive cover is open.