ชไนเดอร์ MCB-EA9AN4C20

Schneider MCB-EA9AN4C20 is a miniature circuit breaker belonging to the Easy9 series.

– Basic Information: MCB stands for miniature circuit breaker; EA9AN is the model number; 4 indicates a 4-pole configuration; C denotes the trip curve type; และ 20 represents a rated current of 20A.

– แรงดันไฟฟ้าที่ได้รับการจัดอันดับ: The rated operating voltage is 400V, suitable for AC 50Hz circuits.

– ทำลายความจุ: Both the rated ultimate short-circuit breaking capacity (Icn) and rated service short-circuit breaking capacity (Ics) are 6kA, with a current-limiting class of 3.

– Tripping Characteristics: Equipped with a thermal-magnetic release and a C-type trip curve, the magnetic trip threshold is 5–10 times the rated current. It is suitable for protecting general-purpose loads and power distribution cables.

– Mechanical and Electrical Service Life: The mechanical service life is 20,000 operations, and the electrical service life is 10,000 operations.

– วิธีการติดตั้ง: Secured by a locking clip, it can be mounted on a DIN rail. The wiring adopts tunnel-type terminals, compatible with wires of ≤25mm² cross-sectional area, with a tightening torque of 2.5N·m.

– ขนาด: The width is 72mm (a multiple of 9mm, 8 ครั้ง), the height is 81mm, and the depth is 70mm.

– Product Certifications: Complies with standards such as IEC 60898-1 และจีบี 10963.1, certified by CCC, and meets the requirements of RoHS and REACH regulations.

For Schneider MCB-EA9AN4C20, a 4-pole C-type miniature circuit breaker, the quality of installation directly affects its protection performance and service life.

1. ข้อกำหนดสภาพแวดล้อมการติดตั้ง

– The ambient temperature shall be maintained between -5℃~+40℃, with the average temperature not exceeding 35℃ within 24 ชั่วโมง. If installed in an enclosed cabinet, ensure good ventilation of the cabinet to prevent malfunction of the release caused by high temperatures.

– Avoid installation in locations with corrosive gases, vapor, or dust (เช่น, metal powder, conductive dust) to prevent contact oxidation or degradation of insulation performance. For humid environments (เช่น, power distribution in basements or bathrooms), a waterproof distribution box must be used.

– The installation altitude shall not exceed 2000m. For installations above this altitude, derating is required or technical support from Schneider should be consulted.

2. Mechanical Installation Specifications

Rail Compatibility: It can only be mounted on a 35mm DIN rail compliant with IEC 60715 มาตรฐาน. The rail must be flat and free of deformation. During installation, use the breaker’s built-in locking clip to fasten it securely to the rail, ensuring no looseness (to avoid terminal heating caused by vibration-induced loosening).

Clearance Requirements: Reserve at least 5mm of heat dissipation space on both sides of the breaker, and maintain a distance of not less than 10mm from other electrical components above and below to prevent heat accumulation between components.

Mounting Orientation: Vertical installation is recommended, with the operating handle facing upward (the “ON” position for closing, และ “OFF” position for opening). If horizontal installation is necessary, ensure that the force direction of the release is consistent with the direction of gravity to avoid affecting the accuracy of overload protection.

3. Electrical Wiring Requirements

Terminal Specifications: Compatible with copper-core wires with a cross-sectional area of 1.5mm²~25mm²; aluminum-core wires are prohibited (prone to oxidation leading to poor contact). Before wiring, strip 8~10mm of the wire insulation to ensure the conductor is fully inserted into the terminal.

Tightening Torque Control: The tightening torque of the terminal screws must be strictly controlled at 2.5N·m. Insufficient torque will cause excessive contact resistance and heating, while excessive torque will damage terminal threads or the breaker housing.

Phase Sequence and Wiring Method: As a 4-pole breaker, wiring must follow the sequence of L1, L2, L3, เอ็น. ลวดที่เป็นกลาง (เอ็น) cannot be reversed or omitted; มิฉะนั้น, the neutral current cannot be monitored in case of three-phase imbalance, resulting in loss of protection function.

Load Matching: The rated current of the connected load shall not exceed 20A, and the load type must comply with the application scope of the C-type trip curve (general lighting, power distribution, small motor loads). It is prohibited for use with high-impact loads (เช่น, large compressors, electric welders).

4. Post-Installation Inspection Items

– Before closing the breaker, manually operate the handle to open and close it 3–5 times to check that the mechanism operates flexibly without jamming.

– Use a multimeter to measure the continuity between the incoming and outgoing terminals of the breaker: it should be conductive when closed and disconnected when opened, with no short-circuit or open-circuit abnormalities.

– During commissioning with power on, first close the breaker under no-load conditions and observe for abnormal noise or heating. Then connect the rated load; after 1 hour of operation, use a thermometer to measure the terminal temperature, with the temperature rise not exceeding 40K.

5. Safety Operation Precautions

– Installation and wiring must be performed under power-off condition; live operation is strictly prohibited. If installed in a power distribution cabinet, cut off the upstream power supply first and hang a “No Switching On” warning sign.

– After installation, affix clear circuit labels on the surface of the breaker (เช่น, “Three-phase circuit for office area on the 3rd floor of the office building”) to facilitate future maintenance.

– Do not disassemble the breaker housing or modify the release without authorization; มิฉะนั้น, product certification will be invalidated, and protection failure may occur, leading to safety accidents.