معنى أرقام الخطوط الثانوية في خزائن التوزيع

S econdary line numbers in خزائن التوزيع are numbering systems used to identify the connection relationships of wires in secondary circuits (يتحكم, حماية, قياس, إشارة, إلخ.). Their core function is to clarify the function, direction, and connection position of wires, facilitating installation, debugging, maintenance, and fault troubleshooting. The following explains the meaning, coding rules, and applications of secondary line numbers:

1. Core Functions of Secondary Line Numbers
2. Unique Identification: Each wire corresponds to a unique line number to avoid wiring confusion.
3. Functional Positioning: Determine the circuit to which the wire belongs (على سبيل المثال, control circuit, signal circuit, voltage circuit) through the line number.
4. Connection Traceability: Quickly locate the devices and terminals connected to both ends of the wire, simplifying the maintenance process.
5. Standardized Management: Comply with national standards (such as GB/T 6988 Preparation of Documents for Electrical Technology) or industry specifications to ensure system consistency.
6. Composition and Coding Rules of Line Numbers

Secondary line numbers typically consist of circuit numbers, device numbers, terminal numbers, and functional identifiers. There may be differences across industries (على سبيل المثال, power, industrial automation, building electrical), but the following are general rules:

1. Circuit Numbers: Differentiating Functional Types

Circuit nature is identified by numerical ranges, with common classifications:

Control Circuits:

– DC control circuits: 101, 102, 103… (على سبيل المثال, circuit breaker opening/closing control).

– AC control circuits: 1, 2, 3… or 101, 102… (على سبيل المثال, contactor coil circuits).

Signal Circuits: 701, 702, 703… (على سبيل المثال, alarm and indicator light circuits).

Voltage Circuits:

– AC voltage: 601, 602… (على سبيل المثال, secondary circuits of voltage transformers).

– DC voltage: 201, 202… (على سبيل المثال, operating power supply circuits).

Current Circuits: 401, 402… (على سبيل المثال, secondary circuits of current transformers, requiring wires with a cross-sectional area ≥2.5mm²).

Lighting/Heating Circuits: 901, 902… (auxiliary function circuits).

Examples:

– The line number “105” may belong to the 5th wire in an AC control circuit.

– The line number “411” may belong to the 11th wire in the phase A current circuit.

2. Device Numbers: Locating Components

Components in distribution cabinets are identified by letters + numbers, following the circuit identification method or location identification method:

Letter Codes (common components):

K: Relay (على سبيل المثال, K1, K2);

كم: المقاولين;

KA: Intermediate relay;

SB: Push-button switch;

TA: Current transformer;

TV: Voltage transformer;

QF: قاطع الدائرة;

FU: Fuse;

HL: Indicator light.

Numbering Rules:

– Number components in the same circuit according to the action sequence (على سبيل المثال, K1, K2, K3);

– Number by installation zone (على سبيل المثال, zone A device A-K1, zone B device B-K1).

Examples:

– The line number “KM1-13” indicates terminal 13 of contactor KM1.

– The line number “SB2-NO” indicates the normally open contact terminal of push-button SB2.

3. Terminal Numbers: Clarifying Connection Points

Identify the specific positions of device terminals, with the following rules:

Numeric Numbering:

– Terminals of a single component: Numbered from left to right and top to bottom (على سبيل المثال, محطات 1, 2, 3, 4 of relay K1).

– Terminals of combined components: Differentiated by numeric groups (على سبيل المثال, 1-1, 1-2… of terminal block X1).

Special Identifiers:

لا: Normally Open;

نورث كارولاينا: Normally Closed;

COM: Common terminal;

+/-: Positive/negative poles of DC power supply.

Examples:

– The line number “K2-5” indicates terminal 5 of relay K2.

– The line number “QF-FA” indicates the auxiliary contact FA terminal of circuit breaker QF.

4. Functional Prefixes/Suffixes

Some systems add functional identifiers to line numbers, مثل:

ش, V, W: Three-phase AC circuits (على سبيل المثال, U411, V411, W411 indicate phase A/B/C current circuits).

+كم, -كم: Positive/negative poles of DC control power supply (على سبيل المثال, +KM101, -KM102).

بي: Protective earth (على سبيل المثال, PE-100).

ثالثا. Line Number Labeling Methods

1. Direct Printing: Use a dedicated line number printer to print numbers on wire sleeves (على سبيل المثال, PVC sleeves, heat-shrinkable tubes), which are durable and clear.
2. Label Stickers: Paste adhesive labels on both ends of wires, suitable for temporary or large-section wires.
3. Color Coding: Combine with wire colors to distinguish circuits (على سبيل المثال, red for positive power supply, blue for negative power supply, yellow-green for earth).
4. Analysis of Typical Line Number Examples

1. احتياطات
2. Adherence to Standards: Prioritize national standards such as GB/T 6988 and GB/T 5094.2, or internal corporate specifications.
3. Uniqueness: Avoid duplicate numbering within the same system to prevent confusion.
4. Clarity: Line numbers must be wear-resistant, waterproof, and consistently oriented (على سبيل المثال, read from left to right).
5. Logical Order: Number by circuit function groups to facilitate understanding of circuit principles (على سبيل المثال, number control circuits by action sequence).
6. Application of Line Numbers in Fault Troubleshooting

When a fault occurs in a distribution cabinet, line numbers can quickly locate issues:

1. Trace Line Number Paths: Find the devices connected to both ends of the wire based on the line number to check for poor contact or breaks.
2. Compare with Drawings: Check whether line numbers match the secondary schematic or wiring diagram to eliminate incorrect connections.
3. Functional Testing: Confirm circuit functions (على سبيل المثال, control circuit, signal circuit) via line numbers and perform targeted measurements of voltage, continuity, إلخ.

خاتمة

Secondary line numbers serve as the “language system” of distribution cabinets, transforming complex circuit connections into a recognizable symbolic system through standardized numbering rules. Mastering the meaning of line numbers not only improves installation efficiency but also enables rapid problem定位 during maintenance, making it a core skill for electrical engineers and electricians. In practice, it is essential to flexibly apply numbering rules in conjunction with the drawings and specifications of specific projects.