Contactors please explain

Hello,
Could someone please explain the specs of contactors.
The specifications seem to be in the following format for contactors.
For 5 different specs of an AC contactor.
3 NO main contacts + 1 NO auxiliary contact (
Reply to
david.cawkwell
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NO means "Normally Open"
Reply to
VWWall
Unless it is a contactor type FEmAlE-CofE - in which case, NO means "normally closed" unless contacts are properly certificated....
;)
Reply to
Palindr☻me
Otherwise, a female contactor could also be : NO not now -; Janos
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Reply to
Janos Netik
The female of NO has always been MaybE. This results into a NO becoming NC unless quick action is taken. Sometimes expressed as MO "momentary open". ;-)
Virg Wall, PE
Reply to
VWWall
One of them occasionally open contacts.
sQuick..
Reply to
sQuick
NO means that in the de-energised state the contact is open. NC means that in the de-energised state the contact is closed.
3 NO main contacts + 1 NO auxiliary contact is the normal configaration for a direct on line 3 phase motor starter. This uses one of each of the main contacts in each of the three phases and the NO auxiliary contact in the control circuit the latch the contactor closed, when you press the motor start push button. Auxiliary contacts are normally only used in control circuits not as load switching contacts.
BillB
Reply to
billb

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