1、 Explosion proof:

The meaning of the explosion-proof symbol Ex (ia) IIC T6 for instruments:

Symbol meaning of the content of the logo

Explosion proof declaration Ex complies with a certain explosion-proof standard, such as China's national standard

Explosion proof method ia adopts Class IA intrinsic safety explosion-proof method, which can be installed in Zone 0

Gas category IIC is allowed to involve explosive gases of category IIC

Temperature group T6: The surface temperature of the instrument does not exceed 85 ℃

I. E.C.: International Electrotechnical Commission

N. E.C.: National Electrical Code (U.S. A.)

2. Explosion proof classification of electrical components

1. General protection EN50.014

2. Oil immersion protection 0 EN50.015

3. Pressure protection facilities p EN50.016

4. Filling powder q EN50.017

5. Flame retardant shell EN50.018

6. Improve safety factor e EN50.019

7. Intrinsic safety protection i EN50.0120

8. The airtight protection h is not unified

9. Pressure flower protection n not unified

10. Ununified extraordinary measures

2、 Classification of protection levels for instrument casings

As an instrument used in explosive hazardous areas, the protection level of its casing should also be specified and assigned a certain code, that is, an IP level number.

The protection level of the shell specified in IEC144 is represented by a code corresponding to its ability to resist external object impact and puncture, as well as its waterproof ability.

For example, the measurement circuit board of intrinsically safe instruments should not be removed from its casing, otherwise it will violate the low requirements of IP40. The protection level consists of two digits, preceded by the word IP.

GB4942.1-85 Classification of Protection for Motor Enclosures; IEC34-5

*Protection measures: prevent human body from touching or approaching live parts inside the shell and touching rotating parts inside the shell (excluding smooth rotating shafts and similar parts), as well as prevent solid foreign objects from entering the motor.

The second type of protection: to prevent harmful effects caused by water ingress into the motor.

The code IP xx has the meaning shown in the table below.

*Bit representation number

*Bit representation number

Protection level

Describe the meaning

0 Unprotected motor without specialized protection

Solid motor with protection greater than 50mm

Can prevent large areas of human body (such as hands) from accidentally or accidentally touching or approaching live or rotating parts inside the shell (but cannot prevent intentional contact)

Can prevent solid foreign objects with a diameter greater than 50mm from entering the shell

Solid motor with protection greater than 12mm

Can prevent fingers or similar objects with a length not exceeding 80mm from touching or approaching charged or rotating parts inside the shell

Can prevent solid foreign objects with a diameter greater than 12mm from entering the shell

Solid motor with protection greater than 2.5mm

Can prevent tools or wires with a diameter greater than 2.5mm from touching or approaching live or rotating parts inside the shell

Can prevent solid foreign objects with a diameter greater than 2.5mm from entering the shell

4. Solid motor with protection greater than 1mm

Can prevent wires or strips with a diameter or thickness greater than 1mm from touching or approaching live or rotating parts inside the shell

Can prevent solid foreign objects with a diameter greater than 1mm from entering the shell

5 Dust proof motors

Can prevent touching or approaching live or rotating parts inside the shell

Insufficient dust intake to affect the normal operation of the motor