It is essentially a 3A SPDT switch with center-off position, with a diode connected to one switch contact, then tied to the other lead. The resulting connections are simply two leads. In LO position, the AC voltage is essentially halved by the diode, perfectly suitable for incandescent lamps and similar loads such as small heating elements.
To clarify operation, this three position switch has two leads.
OFF - circuit is open
HI - circuit is closed
LO - circuit passes though diode, dropping AC voltage in half
- Attached diode: 1N5408, 3A/1KV
- Connections: two 6" pigtail leads, 18AWG stranded
- Switch is labeled Hi (dual hash), Lo (single hash), Off (circle)
Switch Current Rating