# Step 9: Install the Elbow Actuator and Route Its Cables

> Connect the XT30 (2+2) cable connectors to actuator ID 21, seat it in part 300_15C, and route both cables through their designated openings.

- Page: https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/forearm-assembly/step-9
- Section: Asimov › Asimov 1 › Assemble Asimov 1 › Assemble › Right Arm Module › Forearm Assembly
- Previous: [Step 8: Attach the Shoulder Yaw Joint Plate and Shaft Mount](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/shoulder-and-upper-arm-connection/step-8.md)
- Next: [Step 10: Attach the Elbow Housing Plates](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/forearm-assembly/step-10.md)

> [!IMPORTANT]
> **Assign actuator IDs before assembly**
>
> Assign and verify all 25 actuator IDs before assembling the robot. The robot will not work correctly with missing or incorrect IDs. IDs must be assigned one actuator at a time on the bench; you may need to disassemble the robot if you skip this step. See [Assign Actuator IDs](https://docs.menlo.ai/asimov/1/build/assembly-preparations/assign-actuator-ids.md).

## Parts needed

| Part | Count |
| - | -: |
| EC-A4310-P2-36 actuator (part `300_22X`) (ID 21) | 1 |
| 100 mm single-ended XT30 (2+2) cable | 1 |
| 230 mm double-ended XT30 (2+2) cable | 1 |
| `300_15C` | 1 |

## Instructions

1. Connect the XT30 (2+2) connector of the 100 mm single-ended XT30 (2+2) cable to one port on the EC-A4310-P2-36 actuator (ID 21) and one connector of the 230 mm double-ended XT30 (2+2) cable to the other actuator port. Put the assembly aside.

2. Take part `300_15C` and lay it flat on the surface. Make sure that the port cut out on the body is facing upward toward the ceiling. And the port cut out on the side is facing toward you.

3. Align the actuator with the round hole on part `300_15C`. Route the single-ended XT30 (2+2) cable through the hollow body and the double-ended XT30 (2+2) cable through the cable channel until its free connector exits the side cutout. Make sure that the LED on the actuator align with the LED cut out (above the cable port cut out) on part `300_15C` also.