This turnout is constructed so that regardless of switch point settling,
all rails are powered. Because of this, the metal frog is insulated and does
not carry current. Most locomotives will span the insulated frog without the
loss of electrical pickup; however, engines with an extremely short wheelbase,
or diesels with pickup from a single truck may hesitate or stall at the frog.
This condition is easily corrected by equipping turnouts with an Atlas Snap
Relay (item #200) which, when wired to the Atlas undertable switch machine
(item #65), will energize the frog with track current of correct polarity.