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Push Buttons / Indicator Lamps

Push Button Switches are manually operated switches that are available in many different types: Switches with round or square bodies for mounting in round or square holes, lighted and non-lighted Switches, Indicators, Selector Switches, and more.

Overview Features
Principles Classifications
Engineering Data Further Information

Related Contents

Primary Contents



Terms for Pushbutton Switches

Terms Related to Operating Characteristics

Classifi-
cation
TermAbbre-
viation
UnitDefinition
Force
(torque)
Operating Force
(torque)
OFN, NmThe force (or torque) that must be applied to the pushbutton to move it from the free position to the operating position.
Releasing Force
(torque)
RFN, NmThe force (or torque) that must be applied to the pushbutton to move it from the operating limit position back to the returned position.
Total Travel
Force (torque)
TTFN, NmThe force (or toque) on the pushbutton when it reaches the stopper.
PositionFree PositionFPmm, (°)The position (or angle) of the pushbutton when there is no external force applied to it.
Operating
Position
OPmm, (°)The position (or angle) of the pushbutton when the movable contact changes from the free position state to the operating position state due to an external force.
Release
Position
RPmm, (°)The position (or angle) of the pushbutton when the movable contact changes from the operating position state to the free position state due to the reduction of external force.
Total Travel
Position
TTPmm, (°)The position (or angle) of the pushbutton when it reaches the stopper.
Set PositionSPmm, (°)The position of an alternate operation pushbutton when it is in the self-holding state, or the position (or angle) of a selector switch when it is in the self-holding state.
TravelPretravelPTmm, (°)The distance (or angle) through which the pushbutton moves in going from the free position to the operating position.
OvertravelOTmm, (°)The distance (or angle) through which the pushbutton moves in going from the operating position to the operating limit position.
Movement DifferentialMDmm, (°)The distance (or angle) through which the pushbutton moves in going from the operating position back to the returned position.
Total TravelTTmm, (°)The distance (or angle) through which the pushbutton moves in going from the free position to the operating limit position.
Releasing
Travel
RTmm, (°)The distance (or angle) through which the pushbutton moves in going from the returned position to the free position.
Lock Travel
Alternate
LTAmm, (°)The distance (or angle) through which the pushbutton moves in going from the free position to the set position.

Terminal Symbols

SymbolMeaning
COMCommon terminal
NCNormally closed terminal
NONormally open terminal

Contact Form

NameContact form
Double-throw
Normally closed
Normally opened
Double-break

General Terms

TermExplanation
Chameleon lightingFull-screen lighting in one of 3 colors: red, green, or orange. (Orange is produced by simultaneous illumination
of red and green.)
SimultaneityThis term is used for switches that have more than one contact circuit. It indicates the difference in time or
position between the contacts when all the contacts of the switch are opened or closed in one operation.
LED lightingLED-lighted models are lit with an LED installed
in the base of the Pushbutton Unit.
The LED is mounted internally; it cannot be
removed.
LED-lamp lightingLED lamp-lighted models use the same light source as incandescent lamp-lighted models, with an LED instead
of a filament.
The Lamp (i.e., the LED lamp) and the Pushbutton Unit can be separated.
Incandescent lamp
lighting
Incandescent lamp-lighted models are lit with an incandescent lamp.
The Lamp (i.e., the incandescent lamp) and the Pushbutton Unit can be separated.
Voltage Reduction
Unit
For 16-dia. A16 (M16) models and
22-dia. A22 (M22) models
The Voltage Reduction Unit has a smoothing circuit and
resistor, and lights the 24-VAC/VDC LED lamp by applying
110 (or 220) VAC/VDC directly to the Lamp terminals.
Matrix mountingMounting several Switches in vertical and/or horizontal lines.
Locking SwitchesSwitches that have the functionality to self-hold when the pushbutton is operated.
Horizontal
side-by-side mounting
Mounting Switches side-by-side with the long side of the Switch (rectangular models) horizontal.
Vertical side-by-side
mounting
Mounting Switches side-by-side with the long side of the Switch (rectangular models) vertical.

Terms Related to IEC947 and IEC950 Explanation

No.TermExplanation
1Rated operating
voltage (Ue)
VAC: 120, 240, 380, 480, 500, 600
VDC: 125, 250, 440, 500, 600
2Rated operating
current (Ie)
Specified by the manufacturer on consideration of rated operating voltage (Ue), rated frequency, rated energizing time, area of application, and type of enclosure protection.
3Rated insulation
voltage (Ui)
Determined by creepage distance and the dielectric strength.
The maximum Ue value must not exceed the maximum Ui value.
If there is no Ui value specified, the maximum Ue value is taken as the Ui value.
4Pollution
degree
1. Either no pollutants are present, or only dried, non-conductive pollutants are present (e.g., clean rooms).
2. Basically, only non-conductive pollutants are present, or only transient conductivity occurs due to condensation (indoor locations, such as offices).
3. Conductive pollutants are present, or non-conductive pollutants are present in locations where condensation is expected (e.g., factories).
4. Conductivity due to impurities is a constant possibility, or conductivity is caused by conductive dust, rain, or snow (e.g., outdoor locations).
5Electric shock
protection
class
Class I: These devices require grounding. Electric shock is prevented by basic insulation and charged parts that would be subject to dangerously high voltages if the insulation was damaged, are grounded.
Class II: Electric shocks are prevented by double insulation or enforced insulation.
Class III: No countermeasures against electric shocks are required because the electric circuits in use operate in a low-enough voltage range.
6PTIProof tracking index.
Specified CTI values (comparative tracking indices):
Materials satisfying the 175, 250, 300, 375, and 500 levels are denoted as PTI-175, PTI-250, PTI-300, PTI-375, and PTI-500 respectively.
7IPIP-(1)(2) (IEC529)
Meaning of first number-Degree of protection against solid materials and people (See below.)
Meaning of second number-Degree of protection against water (See below.)
No.Meaning of first numberMeaning of second number
Degree of protection against
solid materials
Degree of protection for
people
Degree of protection against
water
0No protectionNo protectionNo protection
1No penetration by any solid
object with a diameter of
50 mm or more.
Cannot be touched with the
palm of your hand.
Protects against vertical drops
of water.
2No penetration by any solid
object with a diameter of
12.5 mm or more.
Cannot be touch with fingers.Protects against drops of water
approaching at a maximum angle
of 15° to the vertical.
3No penetration by any solid
object with a diameter of
2.5 mm or more.
Same as at left.Protects against sprinkled water.
4No penetration by any solid
object with a diameter of
1.0 mm or more.
Same as at left.Protects against water spray.
5Protection against dustNo penetration by any object with
a diameter of 1.0 mm or more.
Protects against water jet spray.
6DustproofNo penetration by any object with
a diameter of 1.0 mm or more.
Protects against high-pressure
water jet spray.

Recommended Products

A16

Separate Construction with Cylindrical 16-dia. Body

A22

Install in 22-dia. or 25-dia. Panel Cutout (When Using a Ring)

A3P

Large Rectangular-bodied Lighted Pushbutton Switches