T4 Explosion-Proof Certification Unit for Guided Robot, Shenzhen Zhongnu Inspection

Shenzhen ZhongNuo Testing Technology Co., Ltd. is based in South China, specializing in explosion-proof certification and coal mine safety certification application consulting services, offering a one-stop explosion-proof technology consulting service.
Explosion-proof fundamentals: Ignition temperature, ambient temperature, and temperature classes
Ignition temperature, ambient temperature, and temperature classes are several common basic concepts in explosion-proof certification.
Ignition temperature refers to the low temperature at which gases or vapors in an explosive atmosphere are ignited.
Ambient Temperature Group refers to the temperature of the environment in which equipment used in explosive areas operates, typically ranging from -20°C to +40°C according to the GB/T3836 standard. No additional ambient temperature label is required at this time. However, if the equipment is intended for use in an environment outside the above temperature range, it is considered a special case. The label should include compliance with Ta or Tamb, as well as the upper and lower ambient temperature limits. If not feasible, compliance with "X" should indicate the special usage conditions including the upper and lower ambient temperature limits.
Temperature groups refer to the high surface temperatures of explosion-proof equipment in explosive areas, typically ranging from T1 to T6.

"Comprehensive Summary: Basic Knowledge of Explosion-Proof Safety Certification and Certification Bodies"
Intrinsically Safe Certification (Intrinsic Safety Certification) is a system designed for electrical equipment used in hazardous environments, which prevents the generation of sparks or high temperatures capable of igniting explosive mixtures by limiting energy (electrical and thermal). The basic principles and applicable standards are as follows:
I. Key Points
1. Fundamental Safety Principle
The core principle is to limit the energy of electrical equipment through design, ensuring that sparks or thermal effects generated during normal operation or in the event of a fault cannot ignite surrounding explosive mixtures (gases, vapors, dusts, etc.).
2. Equipment Categories
Level IA: Ensures safety in both normal and two-fault operating conditions, suitable for Zones 0, 1, 2 and Zones 20, 21, 22.
Ib level: Ensures safety under normal operation and one fault condition, suitable for Zones 1, 2, and 21, 22.
IC level: Ensures safety during normal operation; suitable for Zones 2 and 22.
3. Equipment Requirements
Safety barriers are typically used in conjunction with "safety interlocks" (associated equipment). These interlocks are installed between hazardous and non-hazardous areas to limit the energy entering the hazardous zone and prevent high-energy transmission from the non-hazardous area to the hazardous zone.
4. Circuit Design Requirements
Utilize low-power components, restrict capacitors and inductors in the circuit (to avoid excessive energy storage).
Conductor cross-sectional area and insulation grade must comply with regulations to prevent short circuits or electric leakage.
The circuit must pass spark and hot surface tests to verify its safety.
Section 2: Applicable Standards
1. Standard (GB)
GB/T 3836.1-2021: Explosive Atmospheres – Part 1: General Requirements for Equipment
GB/T 3836.4-2021: Explosive Atmospheres – Part 4: Intrinsic Safety “i”
2、（IEC）
IEC 60079-0: Explosive Atmospheres, Part 0: General Requirements for Equipment
IEC 60079-11: Explosive Atmospheres – Part 11: Intrinsic Safety “i”
3. EU Standards (EN)
EN 60079-0: Explosive Atmospheres - Part 0: General Requirements for Equipment
EN 60079-11: Explosive Atmospheres - Part 11: Intrinsic Safety "i"
4. Other Regional Standards
USA: UL 913 (Intrinsically Safe Equipment Standard)
Canada: CSA C22.2 No. 157 (Intrinsically Safe Equipment)
This explosion-proof certification is applicable to low-power equipment such as communication devices, sensors, instruments, and small control units, and is widely used in industries with explosive environments, including oil, chemicals, coal mines, and pharmaceuticals. The certification must be carried out by qualified explosion-proof inspection institutions (such as the Explosion-Proof Electrical Product Quality Supervision and Inspection Center) to ensure that the equipment meets safety requirements.
As a third-party organization specializing in explosion-proof certification for many years, Shenzhen Zhongnuo Testing Technology Co., Ltd. has dedicated engineers in intrinsically safe circuit and structural design. We offer technical consultation for explosion-proof circuit design, drafting, and modifications, and have extensive experience in designing and obtaining certifications for intrinsically safe IA, IB, and IC classifications. If you require certification in this area, feel free to message us!

What is the difference between ATEX certification and explosion-proof certification?
Intrinsically Safe and Externally Ventilated Explosion-Proof certifications are two common types of explosion protection with distinct differences in their principles. These differences are mainly reflected in the following aspects:
Explosion-proof certification typically involves using explosion-proof enclosures. These enclosures must have sufficient thickness and strength, as even if an explosion occurs inside the equipment, the flame will be extinguished due to the width, gap, and roughness of the joint surfaces of the explosion-proof enclosure, thereby igniting the external hazardous environment. On the other hand, even if an explosion occurs in the external hazardous area, the explosion-proof enclosure exhibits anti-explosion properties. In summary, explosion-proof enclosures can withstand and resist explosions, but the equipment tends to be bulky.
The intrinsic safety certification, which ensures fundamental safety, is achieved by limiting circuit energy, etc., so that even in the event of an anticipated fault, the energy produced is not sufficient to ignite surrounding explosive materials. Therefore, intrinsic safety products have higher requirements for equipment circuits and working power, and are generally suitable for handheld devices, low-power products, etc.
Additionally, there is a composite explosion-proof certification. This indicates that the product cannot achieve explosion-proof with a single type of explosion-proof design; it must utilize two or more types. For instance, explosion-proof equipment with antennas, where the antenna section is typically intrinsically safe, making the equipment both explosion-proof and intrinsically safe. However, it's important to note that a composite explosion-proof product does not mean the product must meet all the requirements of different explosion-proof types simultaneously, and its explosion-proof rating is not necessarily higher than that of a single type. The explosion-proof rating of the product mainly depends on the gas/dust category, temperature group, and equipment protection level.
For more information on explosion-proof certifications like intrinsic safety and flameproof, please feel free to consult Shenzhen ZhongNuo Testing Technology Co., Ltd. at any time.

What does it mean by Zone 0, Zone 1, and Zone 2 in explosion-proof certification | ZhongNuo Inspection
In flammable and explosive hazardous areas, the site must be divided into explosion-proof zones based on the frequency and duration of hazardous material occurrences, to ensure the correct selection and installation of electrical equipment in hazardous areas, aiming for safe operation. Divisions are made according to explosion-proof standards,
Explosive gas environments are classified into Zones 0, 1, and 2. Zone 0 is hazardous, referring to situations where explosive gas mixtures are present for extended periods under normal conditions, such as within oil and gas transmission pipelines. Correspondingly,防爆 zones for explosive dust environments are divided into Zones 20, 21, and 22.
Dividing explosion-proof zones is crucial for selecting the appropriate explosion-proof electrical equipment. For instance, Zone 0 requires intrinsically safe IA electrical equipment, while Zone 1 allows for both IA and IB intrinsically safe equipment, offering a broader selection range.
For more information on explosion-proof solutions, please feel free to contact Shenzhen Zhongnuo Testing Technology Co., Ltd. for further communication.
Explosion-Proof Certification Application Consultancy Services - Shenzhen ZN Testing Technology Co., Ltd.