Terminal Crimp Connection Requirements For Parking Heater

- Oct 29, 2020-

Outline requirements 

  The crimp connection of the parking heater is carried out with the aid of valid drawings. The special crimp dimensions (crimp height and width, etc.) of the components are specified in the drawings of different terminal manufacturers and components. The preset crimp size is accurate. Matched wire cross-sections and terminal pieces should be processed with matching crimping equipment. 

1. Wire 

  Only single copper wire with brightening or surface treatment is allowed. According to the parking heater standard, it is clearly stated that it is not used for solid wires, aluminum wires or flat wires, and the wires are not tinned or soldered. It is not allowed to use materials that affect its electrical conductivity, such as materials with harmful gases or oxygen aging in the insulation.

  Provide sufficient proof that the wire can continue to be used after storage for more than two years and its material must meet the standard parts drawings corresponding to the parking heater and the wire. 

1) Peeling 

  Stripping requires the use of special tools. The stripping length should be monitored by special equipment. 

  Cut the number of copper wires according to the maximum x% of the existing wire model. The calculated value should be based on an accurate value. When the square number of wires is greater than 25, the number of cut copper wires is not allowed to exceed 30.

  X=5 Wire ≤0.5mm 

  X=8 Wire ≥0.75mm

Example 1: Number of copper wires 7 (Type A wire : 0.35mm) 

  5%*7=0.36, the result is close to 0, and the copper wire is not allowed to be cut

Example 2: The number of copper wires is 32 (B type wire: 1.0mm²)

  8%*32=0.36, the result is close to 2. It is allowed to cut two copper wires at most. Wire running is not allowed, in addition, copper wire breakage or insulation damage is not allowed.

  The stripped wire does not need to be processed immediately. Take protective measures (such as passing through the insulating sleeve) before the stripped end is broken. A single wire break is not allowed.

  The surface of the stripped copper wire is not allowed to have any residues of insulation.

  Defective insulation: avoid equipment damage to wire structure during crimping

2) Wire end

  After crimping, the wire end is allowed to reach a maximum of 1mm. The plug-in function, lock function and screw function terminals do not affect their functions. When grounding the terminal, the end of the wire should not reach the surface of the screw.

  When using completely sealed plug-in terminals, no overhangs are allowed. When just plugging in the terminal, 0.4mm is allowed.

  The insulated end between the wire and the insulated crimp tube is visible. No insulation is allowed at the wire crimp.

2. Requirements at the crimped terminal

1) Terminal pieces

  The terminal pieces used must comply with the special requirements and regulations of the parts drawings, and no joint damage or distortion is allowed. It needs to be coiled and erected during transportation.

  When the performance of the terminal piece changes, such as oxidation, it is not allowed to be used after aging.

  The terminal can still be used after 2 years of storage. The terminal material complies with the parking heater standard and complies with the corresponding drawings.

2) Damaged

  The terminal section and groove are not allowed to be damaged or deformed during the crimping process, and the terminal assembly is not allowed to be used again when it is deformed during the crimping process.

3) Bending and rotating

  If there is no special description on the part drawing, it should be used for the following requirements, and the longitudinal bending angle of the curled section is allowed to exceed 3°.

The longitudinal bending angle of the crimped section is not allowed to exceed 5° downward or downward, and the crimped section is rotated to the maximum allowable 5° of the terminal

4) Wire crimp size

  The thickness of the terminal material within the crimping range is based on the part drawing, and the crimp size should be limited. If the actual size deviates from the standard specified in the drawing, it should also be within the range specified in the drawing.

  The specified crimp size should be binding and set by the harness manufacturer.

1. Crimping height

  The size is not adjusted according to the crimping tooling. The crimp height is based on the size specified by the terminal manufacturer on the drawing.

  If there is no special description on the crimping height tolerance of the terminal parts on the part drawing, the height is applicable to the following general tolerance requirements.

  Crimp height range (crimp height range (mm) 0.22-0.5, 0.5-2.5, >2.5)

2. Crimp width

  The size is not adjusted according to the crimping tooling, but according to the terminal manufacturer's regulations. Tolerances conform to the specifications on the standard part drawings.

3. Measurable crimp width

  The crimp width at the bottom of the crimp is not damaged, and a screw micrometer can be used. The terminal manufacturer specifies.

4. Support angle

  The support angle is measured from 6 angles up to 30°, aw≤30°

  Tolerance (mm) ±0.03±0.05±0.1

5. Support height

  The crimping claws contact and support each other. The minimum requirement is the support height. The crimp claws and the terminal materials have the same strength.


6. Curl end spacing

  The curling of the bottom of a different lap foot is allowed. Generally, the supporting length, supporting angle and distance of the curling claw end are fixed. The bottom end without curling claws is allowed to touch its inner wall.

7. The distance between crimping claw ends

  The distance between the curling claw and the bottom of the curling CFE≤0.5*S

8. Burr height

  The height of the tip is affected by the degree of wear of the crimping tool and the insertion device.

Burr height: Gh≤1*S

9. Burr width

Burr width: Gb≤0.5*S

10. Bottom thickness

Bottom thickness: Sb≥0.75*S

11. Crimp

  The manufacturer guarantees to provide terminal components. Because a good crimp should maintain the specified crimp size. A good crimp should have the characteristic of filling the crimp sleeve completely. A single wire is crimped completely within the wire crimp range. The crimp is opened due to asymmetric crimping. Different wire distribution or crimp height. Unsuitable tolerances of wire cross-section and material strength are not allowed.

5) Appearance

1. Appearance of crimping crimping length

The crimping of the wire before and after crimping must exceed the total length and be closed. The curl supports are opposite.

2. Tearing

Tearing is not allowed.

3. Export

  A bell-shaped exit is required on the rear edge of the crimped wire (toward the wire). The gap or separation of this exit obstructs the exit that is not specified in front of the crimped wire (after the terminal). The maximum size of an exit is allowed, the same as its entrance.

6) Insulation crimping

 The insulation crimping of the terminal assembly matches the standard drawings of thin-wall or thick-wall wires.

1. The position difference of the insulation crimp

The crimping crimp is 5 forwards and 3 backwards in this area.

2. Insulation crimping A (crimp crimping)

① Crimp width

  The specified crimping width and height must be met, and at least 1/3 of the wire wrapped crimping (120°).

② Crimp height

③ Surrounding angle

  The crimping claw must be immersed in the insulation. The crimping claw can pass through the insulation, but it is not allowed to damage the wire.

  According to EN6035-2, the bending test must be satisfied (the wire does 3 cycles of motion)



3. Insulation crimping B (surround crimping)

  At the maximum wire cross-section, the crimping crimp will at least completely cover the material thickness.

4. Insulation crimping C (lap crimping)

  At least 2/3 wire wrap in insulation crimping. The wire wrap is closed (lapped). The crimping claw touches, but the wire is not allowed to be damaged.

  The results of the bending test comply with DIN EN 60352-2 (three cycles of wire movement)

7) Single wire sealing crimping

  The crimping claw is as curled as possible to ensure that there is no obstruction when inserting the sheath

1. Location of single-line seal

 The insulated crimping arm must be completely prevented from being on the rain plug. Do not over-clamp the rain plug, damage it or pierce the crimping claw. The location of the rain plug matches the technical drawing.

2. Symmetrical O-shaped single wire crimping (O-shaped crimping)

  The crimping and crimping of single wire insulation is up to 360°, and the crimping claws are not allowed to overlap

3. Asymmetrical O-shaped single wire crimping (surround crimping)

Minimum 360° crimping and crimping of single-wire insulation

4. Other requirements

1) Connecting ribs

  1. After crimping, the connecting ribs shall not exceed the thickness of one terminal strip at most, and shall not exceed 0.5mm.

  2. Burr allowed at the corner cut: the thickness of the metal sheet t≤0.4, 0.4<t≤0.8, t>0.8

  3. The ribs and burrs of the terminal do not affect the insertion function in the sheath.

  4. When using sealed plug-in terminals, the maximum connecting rib is 0.3mm.

  5. Burrs are not allowed at the connecting ribs. Ribs and burrs are not allowed to scratch the rain plug.

  6. It is required to facilitate disassembly and replacement of new terminals during rework.