Electrical Switch Ratings

[Muckin_Slusher]

Came across these switches and I'm baffled.

Any guesses why? Just an incredibly conservative rating because UL?

If the little tiny switch can handle 75 amps at 28VDC, surely the big fucker with bolts for lugs can handle more than 20 amps at 12VDC.

 

[CarterKraft]

Came across these switches and I'm baffled.

Any guesses why? Just an incredibly conservative rating because UL?

If the little tiny switch can handle 75 amps at 28VDC, surely the big fucker with bolts for lugs can handle more than 20 amps at 12VDC.

Probably the UL listing. I don't think there is many UL listed DC switches I can think of.

I have found though just looking at the rotary switches online the ratings are all over the place and many are not even rated for their purpose.
Even the mini blue sea switches are having problems at high sustained currents in solar powered RV systems, they are changing to the larger series switches to keep them from melting.

The flaming river brand seems to be pretty decent in quality but the Pollak brands we always used were good too.
Even so you have to be careful as to which switch you get because the ratings vary wildly.