STANDARDIZED RELAYS — Description (Base K11)
EL-3prose procedureGeneric relay-theory reference (base K11). Relay contact-type codes: 1M (1 make), 2M (2 make), 1T (1 transfer/SPDT), 1M·1B (1 make 1 break). Applies across all wiring diagrams.
Description
NORMAL OPEN, NORMAL CLOSED AND MIXED TYPE RELAYS
Relays can mainly be divided into three types: normal open, normal closed and mixed type relays.
TYPE OF STANDARDIZED RELAYS
1M
Meaning1 Make (single NO contact)
2M
Meaning2 Make (two NO contacts)
1T
Meaning1 Transfer (SPDT changeover)
1M·1B
Meaning1 Make 1 Break (one NO + one NC contact)
NOTE
Generic relay-theory reference. The relay-type codes (1M/2M/1T/1M·1B) are used throughout the wiring diagrams to indicate which internal contact arrangement a given relay uses. Useful when substituting relays or interpreting relay symbols in schematics.