Make Before Break Relay Contacts

You may know about mbb when purchasing a relay.

Make before break relay contacts.

These are also called continuous contacs. It is more normal to use two separate relays and control them at different times if you really need make before break. In general relays are break before make since they work by a single leaf moving between two contacts. Switch and relay contacts are usually made of springy metals.

Is there such a thing or a specific term for break before make relay that can delay between breaking and making connection. When the contacts strike together their momentum and elasticity act together to cause them to bounce apart one or more times before making steady contact. The generic symbology for n o. That is the no and nc contacts are never simultaneously closed during the transition between states this is not always the case form c contacts follow this rule while the otherwise equivalent form.

Multiposition switches can be either break before make most common or make before break. In most cases the rule is break before make or b b m. A late break contact has the operator rigged so the nc contacts won t open until after the no contacts have closed and normal nc contacts are opened. In short it simply means shorting the circuit before disconnecting it.

Make before break mbb is a term denoting a switch or other device in which a new electrical connection is made before the existing one is broken. If these exist they are very rare as most relays have only two states on off. Where a switch contains both normally open no and normally closed nc contacts the order in which they make and break may be significant. To get a make before break you effectively have to have two completely separate contact systems which operate at different times.

The poles of a switch refers to the number of moving contacts while the throws of a switch refers to the number of stationary contacts per moving contact. Relays with mbb contacts have an overlapping mechanism where the no contacts close before the nc contacts open. Mbb contacts is an abbreviation for make before break contacts. Make break relay high power no contacts 12v 70a 3 8 22 more info make break mini relay high power no contacts 12v 70a with resistor 1.

Switch contacts is as follows.