Preparing External Power Cables and Ground Cables with OT Terminals

Recommended Tools and Materials

The recommended tools and materials for preparing external power cables (example in this document) and ground cables with OT terminals are as follows:

• Tools:
  • Power cable crimping tool
  • Hydraulic pliers
  • Box cutter
  • Diagonal pliers
  • Wire clipper
  • Heat gun
• Materials:
  • Power cables
  • Insulation tapes
  • OT terminals
  • Heat shrink tubes

Procedure

1. Peel off a section of the insulation layer C from the power cable based on the cross-sectional area of the power cable conductors. A section of power cable conductor D with a length of L1 is exposed, as shown in Figure 7-42. Table 7-13 lists the recommended lengths of the insulation layer to be peeled off (L1).
   Figure 7-42 Peeling off the insulation layer of the power cable
   
   • When peeling off the insulation layer of the power cable, take care not to scratch the conductor of the power cable.
   • You can adjust L1 according to the length of the OT terminal. L1 = L + (1 to 2) mm.
   Table 7-13 Mappings between the cross-sectional area and the length of the insulation layer to be peeled off (L1)

   Cross-Sectional Area (mm2)	L1 (mm)
   1	7
   1.5	7
   2.5	7
   4	8
   6	9
   10	11
   16	13
   25	14
   35	16
   50	16

   Engineers can determine the length of insulation layer to be peeled off by comparing the cable with the connector to be crimped.

2. Insert the power cable into the heat shrink tube A, as shown in Figure 7-43.
3. Insert the bare conductor of the power cable into the OT terminal B, and then press the OT terminal close to the insulation layer C, as shown in Figure 7-43.
   Figure 7-43 Installing the heat shrink tube and OT terminal
   

   After the OT terminal is installed, the length of the bare conductor outside the OT terminal (L2) cannot be larger than 2 mm. If L2 is larger than 2 mm, cut the excess by using the diagonal pliers or wire clipper, as shown in Figure 7-43.

4. Use the power cable crimping tool to clamp the tail of the OT terminal and the contact part of the conductor, as shown in Figure 7-44.
   Figure 7-44 Clamping the tail of the OT terminal with the contact part of the conductor
   

   The crimped shape varies with the crimping mold.

5. Push the heat shrink tube A toward the OT terminal, and cover the crimping area of the OT terminal and the conductor. Use a heat gun to heat the heat shrink tube, as shown in Figure 7-45.

   Stop heating the heat shrink tube once the cable is wrapped by it tightly. Excessive heat may damage the insulation layer of the cable.

   Figure 7-45 Installing the heat shrink tube