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UCR B5 Router Singal drop out and modbus comm error -11


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I've been using this router with a Unistream PLC for some time now.  Its a headless PLC so i'm just using any tablet with VNC as a remote HMI connecting to the router's LAN wifi.   The router isolates the machine's internal network and connects to the building wifi network for access to the internet and a SQL database.  The PLC has a wired connection to the LAN side of the router.  The Router is set as a Modbus TCP client and the PLC polls it every 10 sec to verify it has obtained a WAN IP address.  There is no cellular or sim card function.

Three issues present. 

1. During development phase I had no issues with WIFI signal strength and connection to the tablet even though the router and its antenna are inside a stainless enclosure.  After placing it in production i would constantly get signal drop outs.  The signal strength does fade it just drops out completely and on the tablet I have to wait for the wifi signal to come back and then reconnect the VNC.  Sometimes by the time i get reconnected the signal would drop out again.  I think its just due to the noisy (electrical noise) environment.   I relocated the antenna outside the box and there was considerable improvement but I am still getting signal drop outs.  Is a mobile machine in a washdown food manufacturing environment.  

2.  Every second modbus com to the router fails with an error number of -11.  Even so, it does what I need it to do but  that error code is funny and it kinda bugs me and I wonder if it might be related to the signal drop outs.

3. In unilogic there is a "router init" block.  I'm not sure what its purpose is as there is no help topic on it but I think I would only need to use that if I were using sms messaging or cellular features


I have updated the firmware on the router but that did not make any difference.  I have not updated to the latest unilogc version yet as did not see any related items in the release notes that might help.

Any insight or tips would be appreciated.

Thank you in advance.


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