Dh/dh+ indicators, Diagnostics methods chapter 7 – Rockwell Automation 1775-S5_SR5,D17756.5.5 User Manual PLC-3 FAMILY I/0 User Manual
Page 122

Diagnostics Methods
Chapter 7
7-10
Also, the scanner configured as the master on a peer-to-peer
communication channel declares a peer-to-peer communication minor fault
when it cannot successfully communicate with a slave after two
consecutive retries.
Important: Once set, the peer-to-peer and backup communication minor
status bit remain set until you reset it.
Table 7.B
I/O Channel Indicators for All Scanner Modules
Indicator
Status
Description
CHx
ON
Communication between scanner module and the I/O chassis
on the corresponding I/O channel is properly established.
Configured for
I/O Scanning
FLASHING There is a fault on one or more of the I/O chassis on the
corresponding I/O channel.
OFF
No I/O chassis are configured on the corresponding I/O
channel or the channel is inactive.
CHx
ON
The channel is functioning properly.
Configured for
peerĆtoĆpeer
communication
FLASHING The input file is too small at the processor receiving data. The
slave or master does not exist. Communication retry.
OFF
The channel is inactive.
CHx
ON
The channel is functioning properly.
Configured for
backup
communication
FLASHING The input file is too small at the processor receiving data. The
partner is not responding.
OFF
The channel is inactive.
Table 7.C shows the DH/DH+ status indicators for 1775-S5, -SR5
scanner modules.
Table 7.C
DH/DH+ Status Indicators for 1775ĆS5, ĆSR5 Scanner Modules
Indicator
Status
Description
XMTG
ON
transmitting a message
RCVG
ON
receiving a message
RDY
ON
ready to transmit a message
ERR
ON
programming or communication error detected
DIS
ON
DH/DH+ channel is disabled
DH/DH+ Indicators