wildcatherder
Member
I am using a D4-RS Remote Slave with a DL-405 as the master.
I cannot communicate with the Remote Slave. There is a Link light (amber) on the slave.
Indicator Lights on the Remote Slave are:
PWR - ON (green)
DIAG - OFF
RUN - OFF
I/O - OFF
PAR - OFF
LINK - ON (amber)
I have triple-checked the wiring of the custom-made cable per DL-405 user manual page 4-14.
I have triple-checked continuity from CPU terminal to CPU terminal for the three connections in the cable.
The cable is terminated with 100 ohm resistors across each end TX-to-RX.
The cable is only 25 feet long.
The Master is set to Station 0 with 19200 baud. Other settings for Port 3 are exactly per the example in the DL-405 user manual page 4-13.
The Remote Master is set to Station 1 with 19200 baud.
(Baud rate was reduced on both ends from 38400 as part of troubleshooting)
I do NOT get a Remote Slave 1 Comm Error at the Master - C701 is OFF.
I also do NOT get a Remote Slave Ready indication - C711 is OFF.
I'm beginning to suspect this is not a communications problem.
I have reinitialized all PLC memory and scratchpad and download the program again with no improvement.
The Setup RLL for the remote is in place in the DL-405 and is exactly like the example shown on 4-7 of the D4-RS user manual, with the exception of starting address for outputs being 40503 vice 40502 and only one Remote being used. Also, I have used SP0 as the first item on the rungs rather than the SP1 special relay shown on that page (I don't think one needs to re-initialize the remote on every scan).
Has anyone got ideas about troubleshooting this problem?
I cannot communicate with the Remote Slave. There is a Link light (amber) on the slave.
Indicator Lights on the Remote Slave are:
PWR - ON (green)
DIAG - OFF
RUN - OFF
I/O - OFF
PAR - OFF
LINK - ON (amber)
I have triple-checked the wiring of the custom-made cable per DL-405 user manual page 4-14.
I have triple-checked continuity from CPU terminal to CPU terminal for the three connections in the cable.
The cable is terminated with 100 ohm resistors across each end TX-to-RX.
The cable is only 25 feet long.
The Master is set to Station 0 with 19200 baud. Other settings for Port 3 are exactly per the example in the DL-405 user manual page 4-13.
The Remote Master is set to Station 1 with 19200 baud.
(Baud rate was reduced on both ends from 38400 as part of troubleshooting)
I do NOT get a Remote Slave 1 Comm Error at the Master - C701 is OFF.
I also do NOT get a Remote Slave Ready indication - C711 is OFF.
I'm beginning to suspect this is not a communications problem.
I have reinitialized all PLC memory and scratchpad and download the program again with no improvement.
The Setup RLL for the remote is in place in the DL-405 and is exactly like the example shown on 4-7 of the D4-RS user manual, with the exception of starting address for outputs being 40503 vice 40502 and only one Remote being used. Also, I have used SP0 as the first item on the rungs rather than the SP1 special relay shown on that page (I don't think one needs to re-initialize the remote on every scan).
Has anyone got ideas about troubleshooting this problem?
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