I have purchased and implement 7 of the version 3 routers in an industrial plant application and they work great. I recently purchased several (6) more units and have attempted to connect 2 of them using the identical settings other than the SSID name and static IP address and neither of them will allow the field device to connect with them. I am using them in Access Point mode to connect a WiFi equipped power tool to connect with its control system on a 1 tool to 1 controller basis.

The 2 new routers that I have tried are using version 4 hardware and the previous succesful installations are all using version 3 hardware. What is the difference that could be causing me this trouble?