Question - Kawasaki FH541V

Just finished working on an FH541V, and I have a question about the voltage regulator. The mower was not charging its battery (turned out to be a blown fuse), and I suspected the regulator and did a couple tests. Here's what I found:

- With the regulator not attached to the blower housing (held on by the stator wires only), and the DC out terminal disconnected, the regulator operates as intended.

- When the regulator is attached to the blower housing and the "DC out" terminal is still left disconnected, the regulator does not produce voltage, even though the stator wires are plugged in.

- When the DC Out terminal is attached, the regulator starts producing voltage.

Is this normal? I was under the impression that the regulator should produce voltage whether it's connected to the battery or not.

The mower now runs fine, although I haven't found the cause of the blown fuse.

If the regulator has 3 tangs then the body of the regulator / rectifier is ground.
Some will have a ground strap connecting the mounting bolt to ground if they are bolted into the plastic blower housing.
Electricity has to be able to flow full loop.
No ground = no voltage

It has 3 prongs, two for the incoming AC voltage and one "B+" for the positive DC voltage coming out. I'm assuming the case is ground, since there's no ground wire. It bolts to a metal blower housing.

What I found strange is that, when the regulator is not mounted to the blower housing, I measure from "B+" to the regulator body and get 12-14 volts. But when I mount it to the blower housing, the voltage drops to under 1 volt until I attached the wiring system to the "B+" terminal. Then it goes back to 12-14 again.

How would the regulator being grounded to the engine impact the voltage meter readings? My FX600V also has a case grounded regulator, and it puts out 12 volts whether the B+ lead is connected or not.