Button on Hayward Power Supply

[cschnurr]

I just bought a Hayward evac robotic cleaner.
The power supply has a button right under the ON/OFF switch.
Does anyone know what this button does?
Pushing seems to have no affect on the cleaner when its running.

 

[Mkleisch]

Is that a sight glass?

 

[JoyfulNoise]

Light bulb or fuse holder?

 

[cschnurr]

I've added another picture.


There is a small black button underneath a clear rubber weather protective shield.
Both the button and the ON/OFF switch have weather shield..

My guess was a GFCI reset button, but the warning on the back of the power supply states that it must be plugged into a GFCI protected outlet.

The cleaner is supposed to clean for 2 hours then turn itself off, could it reset the timer?

 

[Bama Rambler]

That's a breaker. The plunger will pop out when it sees an overload. Since it's not tripped, pressing the plunger in will have no effect.