Subnet LED Red

Hi All,

Repeating my question, As I think the first one didn’t get through.

I have recently started using anybus gateway for building communication between drager LEL and L73s. I am have a healthy communication but the red LED on the module for subnet is continuously on. Tried checking wire connections and ran continuity test but everything looks good. Attached is the log file and back up

ACM CONFIG.cfx (501 Bytes)

log_Anybus_LEL.txt (10.8 KB)

LELTESTING.CFG (16.0 KB)

Please let me know if I am missing anything.

Kind Regards
Swaraj Ostwal

You are receiving an error code from your slave device indicating an illegal data address. Please check the address with the slave’s manual. If you have the manual, please share it and I will take a look.

Hi All,

I started using Anybus gaetway for connecting to drager LEL head, which send data to gateway using Modbus RTU. I am trying to connect with the first node. I am successfully able to receive data. However the subnet LED remain red all the time. Not sure what odes it mean. tried doing the wiring check and continuity test as well everything looks good. I tried getting logs which I have attached below with the configuration. I am using this data in L73s in one of my projects. Any input or help will be highly appreciated. Also there are 4 other LEL in the daisy chain but are powered off.

LELTESTING.CFG (16.0 KB)
ACM CONFIG.cfx (501 Bytes)
log_Anybus_LEL.txt (10.8 KB)

polytron-8xx0-modbus-rtu-fieldbus-communication-9033781-ifu-en-us.pdf (2.6 MB)

Hi this was used by the vendor to configure drager LEL. I Also found out, all LELs have same node address (1). To avid issues I just powered one with node address 1.

Hi @Swaraj

Was the LED showing red when it was only connected to one of these LEL devices?

Hi Tim,

Yes, it was showing red even with one. Tried powering off all the LEL still the red light was there.

Kind Regards
Swaraj

Do you have the article number for this device? usually it’s AB followed by a 4 digit number

Its AB 7072-B.

Regards
Swaraj

Thank you for the manual. According to the manual, the error you are getting is:

Checksum error in the data range

And the remedy is:

Perform service init

How to “perform service init” isn’t explained in this manual. Do you know what that means?

Have you tried reading some of the other registers? Like 29 - 33?

I would also recommend contacting the manufacturer. You are receiving a response from the device, so you have the Anybus configured properly. You just need to find out why you are getting errors back.

Hi Kyle,

Thanks for the information, but I am unaware of the service init part. I will reach out to vendor for that.

Regards
Swaraj

Hi Kyle,

Yes I was able to read value from other registers like gas name, calibration date, but the address 507 which gives the actual gas reading, I was not able to see it in the anybus node monitor function. However the Drager LEL showed that value on its display. I think I will reach out to vendor for checking the checksum error, the service init part and also do they have to configure anything to on access part for us to read the gas level form this register.
On other thing besides this anybus, I have 6 more modules used in other panels. I just configured the IP address and one node in each of them. Physically they are not connected to any device however, I still see those red led for all 6 of them for subnet status. Is this normal or there’s any issue with that. I am attaching one file for reference, all I have done is changes IPs for other 5 devices.

LEL CAB01-10.201.8.53 Com128.cfg (16.0 KB)
LEL CAB01-10.201.8.53 Com128.cfx (2.9 KB)

Kind Regards
Swaraj

Yes, I would definitely contact them about how to read that register and about what that error means.

On the other modules, you are getting the red LED (probably LED 5) because they are trying to do cyclic reads every second and timing out.

It doesn’t matter if you aren’t connected to the nodes yet and some times you can get this red LED even with a working configuration if you have a timeout set. If you were using update on change or trigger, or the timeout was disabled, there would be no timeout and the LED would stay green. You may want to increase the timeout a little bit if it’s still on when you are connected to the nodes.

Hi All,

I was able to resolve the issue with respect to subnet led and also with data interface part. So as mentioned anybus configuration was right, the drager LEL had same node address which we figured out in our previous comments, giving them unique node address helped me get the rid of the subnet led issue.
For data there’s a dip switch that needs to be enabled on the device in order to allow actual gas reading to be available in output register. After doing that, it worked and I am working to get it on my PLC.

Having said that, I really thank each one of you for your inputs.

Kind Regards
Swaraj

Great - I’m glad it’s working! I will close the case for now, but don’t hesitate if you have any additional questions.

Hi, I have a similair issue where the subnet LED is flashing red with about a 1sec on/off period. I can’t find any documentation that indicates what the LEDs indicate. Gateway is connected to a stratix switch and talking with a Logix L84ES