Rockwell Automation 855T DeviceNet Stack Light User Manual - Manual (Page 38)

4-8 Operations
Publication 855T-UM001C-EN-P May 2005
Error Mode
Errors are critical and non-critical.
Refer to the troubleshooting chart in Chapter 5 for details on how to recover from an error.
Resetting the Device
To reset the 855T Control Tower Stack Light, you must cycle power to the unit or disconnect
the DeviceNet Cabling
.
DeviceNet Operations
The Allen-Bradley 1747-SDN, 1771-SDN, and 1756-DNB DeviceNet Scanner Modules are
master devices on the DeviceNet Network. The 855T Control Tower Stack Light supports
the Master/Slave Connection Set for master/slave communications on the DeviceNet
Network.
To communicate with 855T Control Tower Stack Light, the DeviceNet Scanner Module must
be configured with the stack light:
• Node Address
• Input bytes (1)
• Output bytes (1)
The DeviceNet Scanner Module:
• connects to the 855T Control Tower Stack Light slave device.
• performs appropriate connection configuration.
• polls the 855T Control Tower Stack Light for I/O.
Table 4.P
Error Type Description
Critical (non-recoverable)
• Failure of diagnostic tests during power-up/reset mode
• Duplicate node address detected
• Incorrect data rate
Non-Critical (recoverable) • Pilot lamp burned out/module missing (power must be cycled to reset Status
Byte once lamp is changed)
• I/O connection timeout