GLOSSARY
MAMCO provides a wide variety of precision switch products for various applications, which means that occasionally we use terms that not everyone may be familiar with.
As a convenience to our website visitors, we have compiled a glossary to ensure that you are getting all of the information you need to get your precision switch and insert molding solutions.
​Actuation Point
Also known as the trip point or set point, refers to the point of operating of the contacts at a given pressure point. Pressure point where the contacts will close on a NO switch or will open on a NC switch.
Adjustable Range
Difference between the lowest and highest adjustable actuation or de-actuation set points of a switch.
Ambient Temperature
Temperature of the environment immediately surrounding a pressure sensing element.
Burst Pressure
This specification is the maximum over pressure condition that the switch can withstand without experiencing leakage.
Contact Resistance
Electrical resistance of a pair of closed contacts
Dead Band
Area from slightly above zero gauge pressure to slightly below, within which sensor travel is not sufficient to reliably actuate a mechanical switch.
De-Actuation Point
Temperature of the environment immediately surrounding a pressure sensing element.
Differential
This specification is the maximum over pressure condition that the switch can withstand without experiencing leakage.
Field Adjustable
A switch that has been designed for adjustment or calibration of set points in field application.
Contact Arrangement
Refers to the type of circuit or contact form for the switch. Ex: SPST, SPDT, Normally Open or Normally Closed
Electrical Contacts
The elements in the switch that electrically respond to the media applied to the actuator.
Factory Calibrated Switch
The switch is not designed for field adjustment of set points. The switch can be ordered pre configured for immediate shipment or as a standard product, tailored to user needs.
Capacitive Load
A load which the current leads the voltage
Inductive Load
A load in which the voltage leads the current
Media
Liquid or Gas the switch will be monitoring.
Motor Load
The load of a motor at rated horsepower and speed.
Operating Pressure Range
A range of inlet pressures in which the switch will operate correctly.
Pressure Switch Actuator
The member in the switch which receives the media and ultimately signals the electrical contacts to pen or close at the designated set point.
Pressure/Vacuum Switch
​A device that senses a change in pressure/vacuum and opens or closes an electrical circuit when the point is reached.
Proof Pressure
The specification is the maximum over-pressure condition that the switch can have for a specified period of time and still maintain set point integrity.
Pressure Sensing Element
The portion of the switch that is in contact and moves as a result of change in pressure. The most common types of pressure sensing elements are diaphragms, bellows, bourdon tubes, and pistons.
Set Point
The pre-determined pressure/vacuum value that is required to open or close the electrical contacts in the switch.
Snap-Action Switch
A mechanically operated electric switch which, once its actuator has reached its operating (or release) point, immediately transfers to its opposite position without further travel of the actuator.
Switch Contact Forms
Form A 1PST- NO
Single pole, Single throw, normally open
Form B 1PST- NC
Single pole, single throw, normally closed
Form C 1PDT- 1 NO/ 1 NC
Sing pole, double throw, break before make
Form X 1PST-NO DB
Single pole, single throw, normally open, double break
Form Y 1PST-NO-DB
Single pole, single throw, normally closed, double break
SPDT- Single Pole Double Throw
The switch has three terminals, one normally open, normally closed and a common terminal.
SPST-Single Pole Single Throw:
Normally Closed and a common or Normally Open and a common terminal.
Switching Element- Normally Closed
A normally closed switch conducts electricity until the actuator is moved by the media causing the contacts to open.
Switching Element- Normally Open
A normally open switch does not conduct an electrical signal until the actuator is moved by the media causing the contacts to close.
Wetted Parts
Components of a switch that are directly exposed to the media.