Two Wireless Bridges losing connection

Hello,

My customer has a PLC 1769-L30ERMS connected to a switch 1783-BMS10CGN. On this switch, we have the Wireless Bridge II (AWB3000-B) which communicates with another Wireless Bridge II (AWB3000-B). That second Wireless Bridge II is connected to a device port of a 1783-ETAP. On that ETAP, I have a 1734-AENT connected to it. Every now and then, I’m losing connection between the two Wireless Bridge and the PLC goes into a Fault Status because it doesn’t see the I/O module. We did a ping test and here’s the result below. The two Bridges communicate over Bluetooth. Everything was working really good in the lab but in the smelter environment, we are seeing connection drops. Do you have any idea why? Bluetooth should be much more robust, no?

Thanks

Simon-Julien Elie

Hello Simon,

I have not seen this type of issue with two AWB devices paired. What firmware version are the Bridges on? Have they checked if they are on the latest version? Have they tried using WiFi and did the issue persist? I would also have them check the up time to see if it is the device rebooting.

Deryck

Deryck,

He changed it to Wifi and now, everything works… The customer is requesting explanations since Bluetooth should be more robust.

Thanks

Simon-Julien Elie

Canada Area Sales Manager

I don’t really have enough info to say for sure why.

Bluetooth is more resistant to noise but is limited in other aspects. They could have been sending more data then the AWB was capable and packets were getting lost or the devices were on the edge of the range.

Deryck

The process is pretty stable, there is a VFD and a point IO that pass thru the AWB. In Bluetooth we lost communication every 1 or two days and generally the equipment is doing nothing but waiting and the distance between them is always the same, 18 meters.

How can I know if I’m sending more data than the AWB is capable of?

We switch to wireless and it seem more stable but not perfect as you will see when my new topic will be approved.

Hello @jdboivin,

I have not seen an issue like this before, I’m reaching out to my colleagues in Sweden for more info and will update you regarding both connections issues once I have more info.

In the meantime, do you know if the devices rebooting? You should be able to tell by looking at the uptime in the overview page for each device.

Deryck

Hello Deryck,

I don’t know if device where rebooting. They can reboot in 500ms?

I don’t know the exact start time, in testing it is around 10 seconds for a reboot.

Also, can you confirm want firmware version you are on?

Deryck

If it’s 10 seconds it’s not a reboot.

V1.3.9

Hello @jdboivin,

What is the RPI between the PLC and the remote device and how much data in each package? When you were using bluetooth you might have been exceeding the limits of the connection over bluetooth causing you to start seeing some data loss. Over Bluetooth we have a maximum transfer of 1Mbps and a 10Mbps limit over WLAN.

Deryck

Hello all,

We have released FW 1.5.3 that improves stability and the time it takes for the AWB to reconnect to a network if it disconnects. If you are still seeing any connection issues I recommend updating.

Deryck

A post was split to a new topic: AWB2030 Wireless Bolt Devices communications drop out

We made the change to Wifi, fixed the Wifi channel and never hear of any problem since.

Jean-David

What type of fix to the wifi channel did you make that worked?

Sorry for my English (I’m French Canadian). My theory is that when the access point have difficulty to transmit over a Wifi channel he automatically switch to another channel to improve the signal quality, but during that switch the signal is lost during a few second so alarm in my PLC where popping everywhere. Solution: set a dedicated Wifi channel to the Wifi network that no one use around to avoid switching channel that cut transmission.

@jdboivin, Thanks for the reply. Sounds pretty simple and ensures that no other devices interfere with the channel.