What year MH? Are you plugged into 50 Amp service? Does the EMS monitor show a zero or nothing at all?
If you have a 50 Amp MH, plugged into 50 Amp service the EMS will not show anything. Not needed.
Try a 50 to 30 Amp adapter and you should get a reading or use the generator.
(Turn off the A/C before switching power***switching under load can cost $$$)
Do you have a Manual? If I had known what year you have I would have added a link to Wennabago Ind. Manuals are free to download.