Honda EM50is Owner's Manual page 70

Battery
The battery is either standard parts or optional parts for this generator.
1.Remove the maintenance cover (see page 49).
2.The battery is disconnected and the battery cables and blue coupler
harness are clamped twist clipped into the battery tray for shipment.
Remove the battery strap from the bottom hook, and then remove
the battery. Only remove the battery cables from the twist clip. 
Make sure that the 4-pin blue coupler harness is secured with the
twist clip.
Set the battery.
3.Remove the protective cover from the battery positive (+) terminal,
connect the positive (+) cable to the battery positive (+) terminal.
4.Connect the negative (–) cable to the battery negative (–) terminal.
5.To secure the battery, hook other clasp of the battery strap onto the
bottom hook of the generator.
6.Install the maintenance cover in the reverse order of removal.
Never operate the generator without the maintenance cover in place, as
poor engine and generator performance will result.
4-PIN BLUE COUPLER HARNESS
BATTERY CABLES
POSITIVE (+) CABLE
BATTERY STRAP
68
TWIST CLIP
BATTERY
NEGATIVE (–) CABLE
BOTTOM HOOK