The following are industry accepted relay schematics and forms that GIGAVAC uses for most of its relays.

Shown are:

Single Pole Single Throw – Normally Open (SPST-NO) Form A
Single Pole Single Throw – Normally Closed (SPST- NC) Form B
Single Pole Double Throw (SPDT) Form C
Double Pole Double Throw (DPST-NO) 2 Form C
4 Pole Double Throw (DPDT) 4 Form C
Single Pole Single Throw (SPST) Latching Form P
Single Pole Double Throw (SPDT) Latching Form R
Single Pole Single Throw – Normally Open (SPST-NO) Double Make Form X
Single Pole Single Throw – Normally Closed (SPST-NC) Double Break Form Y

High Voltage and Power Terminal designations are:

Terminal 1 is Normally Open (NO)
Terminal 2 is the moving contact (sometimes called Common)
Terminal 3 is Normally Closed (NC)

Coil terminals designations are as follows (Coils of GIGAVAC relays are not polarity sensitive unless otherwise noted):

X for non-latching relays
X and Y for Latching relays.

Refer to Relay Terminal Designations - Diaphragm style G4- series for specific terminal locations on diaphragm style relays. Refer to data sheet for all others. Unless otherwise specified, coils are not polarity sensitive.