Honda EU22000i Owner's Manual page 37

Parallel operation with EU2000i
For instructions on how to connect the parallel operation cable, refer
to pages 33 and 34.
An EU2200i generator may only be connected to EU2000i or
EU2000i Companion generators that have specific frame serial
numbers. Refer to the table below to confirm that your EU2000i
or EU2000i Companion generator is compatible with an EU2200i.
Models
EU2000i / EU2000i Companion
Frame Serial Number Range
EAAJ-2017305 and later
EACT-1000001 and later
OPERATION
35