What is the acceptance standard of European power control cabinet after installation?

The acceptance standard of European power control cabinets should be combined with its regional specifications, industry standards and safety certification system. The following is an explanation from the aspects of legal basis, technical requirements, test items and acceptance process, covering core standards and practical points:

I. Basis of Regulations and Standards

European union unified standard

EN 60439-1: General standard for low-voltage switchgear and controlgear, specifying the requirements of structure, protection level, electrical clearance, etc.

EN 60204-1: electrical equipment standard in the field of mechanical safety, which specifies the electrical safety design of the control cabinet in the mechanical system.

EN 61439-1/-2: Replace the new standard of EN 60439, and strengthen the short-circuit tolerance, protection level and modular design requirements.

Security and authentication system

CE certification: The control cabinet shall comply with the Low Voltage Directive (LVD 2014/35/EU) and the Electromagnetic Compatibility Directive (EMC 2014/30/EU), and the CE mark shall be affixed.

ATEX certification: If it is used in explosive environment, it must conform to EN 60079 series standards to ensure explosion-proof performance.

Second, the structure and installation acceptance points

1. Cabinet and protection requirements

Acceptance method required by project standards

Protection grade (IP) indoor ≥IP31 (solid foreign body prevention ≥2.5mm, water drenching prevention); Outdoor ≥IP54 (dust-proof, water-proof). Visually inspect the sealing strip, and test it with water spray device.

Material and anticorrosive steel plate thickness ≥1.5mm, surface galvanized or powder sprayed (salt spray test ≥1000 hours without corrosion). Calipers measure the thickness and check the adhesion of the coating.

The mechanical strength cabinet should bear 100N pressure without deformation, and the door shaft should be able to withstand switching operation for 50 times/day and more than 10 years. Pressure test, manual operation test

2. Internal layout and wiring

Electrical clearance and creepage distance:

When the rated voltage is ≤250V, the interphase/relative ground clearance is ≥3mm, and the creepage distance is ≥ 4 mm;

When the voltage is greater than 250 V, it shall meet the requirements in Table 7 of EN 61439-2 (for example, the system gap of 690V is ≥10mm).

Wiring specification:

Wires need to be crimped with cold-pressed terminals, copper bar connections need to be tinned, and the bolt torque meets the standard of EN 60947-1 (for example, M6 bolt torque is 8 ~ 10 nm);

The grounding wire shall be yellow-green with a cross-sectional area of ≥ 2.5 mm (when the PE line current is ≤16A).

Third, the electrical performance test standards

1. Insulation and grounding test

Insulation resistance:

Measured by a 1000V megohmmeter, the insulation resistance between phases and ground shall be ≥ 1mΩ (required by EN 61439-1);

It is allowed to be ≥0.5MΩ in humid environment, but it needs to be recorded and rectified within a time limit.

Grounding system:

Grounding resistance ≤4Ω(TN system), and ≤ 10Ω for IT system;

The cross-sectional area of the grounding copper bar is ≥ 16 mm, and the on-resistance with the metal parts of the cabinet is ≤0.1Ω.

2. Withstand voltage test

Apply AC withstand voltage (1 minute):

When the rated voltage is ≤380V, the test voltage is 2000 V;

The test voltage of 690V system is 2500V, and there is no breakdown or flashover (standard EN 60664-1).

3. Short circuit tolerance

The rated short-circuit current (for example, 30kA/1s) shall be tested, and the components in the cabinet shall be free from deformation and carbonization, and the bus support shall be able to withstand the electromotive force (as required in Appendix F of EN 61439-1).

Four, function and safety acceptance project

1. Verification of protection function

Overload and short circuit protection:

The tripping characteristics of circuit breakers shall conform to EN 60898 (domestic) or EN 60947-2 (industrial) standards, for example, a C-type circuit breaker trips within 10ms at 5-10 times the rated current.

Leakage protection (RCD):

Rated residual operating current ≤30mA (personal protection), and operating time ≤ 0.3s (standard EN 61008-1).

2. EMC compatibility

Have to pass the tests of EN 61000-6-2 (anti-interference) and EN 61000-6-3 (emission limit), such as:

Electrostatic discharge immunity ≥8kV (contact discharge) and radiated electromagnetic field immunity ≥30V/m(80MHz~1GHz).

3. Man-machine safety

The cupboard door shall have a mechanical interlock of "opening after power failure" (Article 5.3 of EN 60204-1);

The emergency stop button shall be red mushroom head type, which can cut off all power supply after being pressed, and it shall be reset manually (EN ISO 13850 standard).

V. Acceptance Process and Document Requirements

1. Acceptance steps

Document review:

Check CE certificate, type test report (such as short circuit test report) and component certificate (such as circuit breaker conforming to EN 60947-2);

Check whether the installation drawings and wiring diagrams are consistent with the Structural Design Document of EN 61439-2.

Field test:

Test item by item according to Appendix D of EN 61439-1, and record data such as insulation resistance, withstand voltage result and protection action time.

Commissioning acceptance:

Run with load for 72 hours, and monitor the three-phase current balance (deviation ≤5%) and temperature rise (copper bar ≤60K, cable ≤40K).

2. Acceptance documents

The Acceptance Report conforming to EN 60300-3-3 shall be submitted, including:

Test data table (such as insulation resistance value and grounding resistance value);

Functional test records (such as RCD action time and short circuit protection response curve);

Deviation description (if there are any nonconformities, please indicate the rectification plan and reinspection results).

VI. Additional Requirements for Special Scenes

Explosion-proof environment (ATEX area):

The cabinet shall conform to the explosion-proof type of EN 60079-0 (Ex d flameproof type, for example), with joint clearance ≤0.1≥8mm and thread engagement length ≥ 8 mm..

Offshore or corrosive environment:

The coating shall pass C5-M certification of ISO 12944, and the cabinet shall be made of 316L stainless steel, and the salt spray test shall be ≥5000 hours.

The acceptance of European power control cabinets should be based on EN standard and CE certification system, and the whole process should be controlled from structural protection, electrical safety, functional compatibility to document compliance. Special attention should be paid to the differences of EMC compatibility, explosion-proof requirements (if any) and grounding system during acceptance to ensure that the equipment meets the safety and performance specifications of the EU market.