Electronics Circuit Symbols help

[JoshM]

Could any of you help me with what numbers 3 and 11 are please? I think I know all the others

 

[Minder]

3 is a Reed Relay and 11 is a normally open (N.O) push button (P.B.) switch.
M.

 

[JoshM]

3 is a Reed Relay and 11 is a normally open (N.O) push button (P.B.) switch.
M.

Thank you

 

[JoshM]

Does anyone know what a reed relay could be used for in a circuit?

 

[Minder]

There are many uses, one common one is they are used in building burglar alarms (usually held closed) to detect window/door opening etc.
Another is in rotary switches etc, and/or any area where a hermetically sealed switch is required. and many more.
M.