O

Break contact

2

OH

Main break contact of a contactor

2

OU

Break contact, overlapping

2

OUF

Break contact, early opening

2

OUS

Break contact, late opening

2

OV

Break contact, delayed

2

OVO

Break contact, delayed closing

2

OVS

Break contact, delayed opening

2

S

Make contact

2

SH

Main make contact of a contactor

2

SU

Make contact, overlapping

2

SUF

Make contact, early closing

2

SUS

Make contact, late closing

2

SV

Make contact, delayed

2

SVO

Make contact, delayed opening

2

SVS

Make contact, delayed closing

2

W

Change-over break before make contact

3

WU

Change-over make before break contact, both ways

3

WV

Change-over contact, delayed

3

WVO

Change-over contact, delayed opening

3

WVS

Change-over contact, delayed closing

3