The IRL540N is the Godzilla of pinball transistors and will replace power FETS IRL530N, 20N10L, 22NE10L. It may also replace non-L versions in typical pinball coil and flash driver circuits - for example, The Guns'n'Roses magnet control board.
Its 100V 26A rating will handle most anything that a pinball machine can do, including peak currents in excess of 100A.
This is a great transistor for replacing Stern flasher drivers (22NE10L).
What does the "L" mean?
This transistor is designed to switch at TTL logic levels. A regular FET is designed to operate as an amplifier, and logic levels only turn them on part way - so thet get hot.
How do I Test an FET With My Meter?
An FET is not like an ordinary transistor, and the typical tests won't work. Here are some hints.
First, the pins. The left pin is the gate. This pin should be electrically isolated from the others. Pin 2 is the source - positive voltage flows in here - and pin 3 is the drain, normally connected to ground.
There is an internal diode across pins 2 and 3. This diode protects against kickbacks from coils.
Now, here's the problem. The gate is very well insulated. So much so that just touching it can leave enough of a charge that the transistor is turned on. That makes your meter read funny between pins 2 and 3. Sometime one thing, sometimes another.
So the only real test that you can do is to look for a connection between pin 1 and pin 2 or pin 3. If you see that, the FET is probably shorted.