Basic knowledge of explosion protection

Explosion-proof mark
Explosive gas equipment classification Explosive gas ignition temperature and equipment allowable maximum surface temperature grouping Explosive gas equipment classification

IP â–¡â–¡ Protection level, IP is the international protection rating symbol (INTERNATIONAL PROTECTION RATINGS), followed by two digits, the first digit indicates the dustproof capability of the device, called the first characteristic number, the second digit indicates the device The waterproof capability is called the second characteristic number.

Anti-corrosion electrical products logo
Explosion-hazardous environment area division In order to correctly select electrical equipment and set up distribution lines in an explosion-hazardous environment, that is, according to different hazardous areas, choose electrical equipment and lines with different degrees of protection (GB50058-92) divides the hazardous area division in the explosive environment, which is consistent with the IEC's division of the explosion hazardous area.
1. Classification of explosive hazardous environment: The explosive hazardous environment is divided into two categories according to the form of explosive substances: gas explosive hazardous environment and dust explosive hazardous environment.
2. Division of explosive gas environment:
The explosive gas environment is divided according to the frequency, duration and degree of danger of the explosive gas mixture. That is to say, according to different situations where the explosive gas mixture occurs continuously or for a long time or for a short time, the zoning is performed.
The explosive gas environment is divided into 3 dangerous areas:
(1) Zone 0: an environment where explosive gas mixtures occur continuously or for a long time;
(2) Zone 1: The environment where explosive gas mixture may occur during normal operation;
(3) Zone 2: An environment in which explosive gas mixtures cannot occur during normal operation, or an environment in which explosive gas mixtures exist only for a short time even if they occur.

Generally, in the flammable gas environment, explosion-proof products must be used when using electrical products. The shells of explosion-proof products generally have the following signs, the specific meanings are as follows:
Ex d â…¡ B T4
① ②③④ ⑤
①, China and International Electrotechnical Commission explosion-proof mark ②, explosion-proof type ③, electrical equipment other than coal mines, underground use ④, according to the maximum experimental safety clearance of explosive gas environment or minimum ignition current is divided into ABC three levels ⑤, according to equipment The highest surface temperature is divided into six groups from T1 to T6

The first bit code:
Ex-China and International Electrotechnical Commission explosion-proof mark; EEx-means European Community; AD-Italy; MS, AE-France; FLP-United Kingdom; UL, FM-United States; E-Germany \ IEC

The second bit code
Code explosion-proof type National standard explosion-proof measures applicable area d Flameproof GB3836.2 Isolate the existing ignition sources Zone1, Zone2
e Increased safety type GB3836.3 Try to prevent the generation of ignition sources Zone1, Zone2
ia Intrinsically safe GB3836.4 Limits the energy of the ignition source Zone0-2
ib intrinsically safe GB3836.4 limits the energy of the ignition source Zone1, Zone2
p Positive pressure type GB3836.5 hazardous materials are separated from ignition source Zone1, Zone2
o Oil-filled GB3836.6 hazardous substance is separated from ignition source Zone1, Zone2
q Sand-filled GB3836.7 hazardous substances are separated from the ignition source Zone1, Zone2
n Non-sparking type GB3836.8 Try to prevent the ignition source Zone2
m Pouring type GB3836.9 Try to prevent the ignition source Zone1, Zone2
h Airtight GB3836.10 Try to prevent the generation of ignition sources Zone1, Zone2
s Special type DIP dust explosion-proof type is used in explosive dust environment, without the need to add EX or EEX signs in front of it. Hazardous location hazard classification:
Explosive substance zone definition Chinese standard North American standard gas (CLASS â… )