General Term Description of Micro Switch

The micro switch has a small contact interval and a quick mechanism, with the specified stroke and force for switching action of the contact mechanism, which is covered by the shell. It has an external actuator, and the shape is small.

1. General terms for micro switches

(1) Contact:

In the type of micro switch, compared with the semiconductor switch with switching characteristics, the switch function is realized through the mechanical switch of the contact.

(2) Circuit Configuration:

An electrical input/output circuit that constitutes a contact according to various uses.

(3) Rated value:

Generally, it refers to the value as the guarantee reference for the characteristics and performance of the micro switch, such as rated current, rated voltage, etc., which is premised on specific conditions (type of load, current, voltage, frequency, etc.)

(4) Insulation resistance:

It refers to the resistance value between non-connected terminals, between terminals and uncharged metal parts, and between terminals and ground.

(5) Pressure resistance:

The threshold value at which no insulation damage will be caused after 1 minute of high voltage is added to the specified measuring position.

(6) Contact resistance:

It represents the resistance of the contact part of the contact, but generally represents the resistance of the conductor including the spring and the terminal part.

(7) Vibration resistance:

False action vibration: The vibration range in which a contact closed by vibration does not separate within a specified period of time when a micro switch is in use.

(8) Impact resistance:

Durable impact refers to that the micro switch will not be damaged by the mechanical impact during transportation or installation, and can meet the impact within the range of action characteristics.

False action impact: It refers to the impact range where the contact closed due to impact does not separate within the specified time when the micro switch is in use.

2. The structure and construction terms of the micro switch

(1) Operation body

It represents the part of the mechanism that operates the switch drive rod. Part of a mechanical device such as a CAM or a block.

(2) Drive rod

A part of a switch that conducts an external force to an internal spring structure that pushes a movable contact to perform a micro switch action, a general term for a button and an operating pendulum rod.

(3) Contact interval

It is the fixed contact and movable contact interval, the effective distance of the switch.

(4) Switch housing

A box body that protects the part of the micro switch mechanism, also called a housing.

(5) Movable film

The mechanism part of a switch contact. Sometimes it is called a movable spring.

(6) Terminals

The wiring operation part of the conductive part of the circuit for electrical input and output.

3. Terms about the service life of the micro switch

(1) Mechanical life: It refers to the switch life when the contact is not energized and the overstroke (OT) is set as the specification value at the specified operating frequency to make it run.

(2) Electrical life: The life of the switch when the rated load is connected to the contact and the overstroke (OT) is set as the specification value at the specified operating frequency.

4. The standard test state of micro switch

The test conditions of the switch are as follows:

Ambient temperature: 20±2℃; Relative humidity: 65±5%RH; Air pressure: 101.3kPa.

5. N horizontal reference value of micro switch

It denotes the fault level under 60% reliability (λ60).

λ60=0.5×10-6/ time indicates that the reliability is less than 60%, the failure rate is less than 1/2,000,000 times.