The circuit symbol for a single-pole single-throw normally-open (SPST-NO) relay
Electrical_symbols_library.svg
SPST-Switch.svg
Electrical_symbols_library.svg: User:FDominec et al.
SPST-Switch.svg: Iainf 22:01, 3 July 2006 (UTC)
derivative work: Moxfyre (talk)