CEGS Cables

Cut Cables and Wire Connectors

Cable Groups

• Front Bar
• Back Bar
• VM
• LN Manifold

Cable Types

• Valve actuators
• Pressure sensors
• Thermocouples
  • Type T
  • Type K (furnaces)
• Control wires
  • Heater control wires
  • Solenoid valves
• Grounding wires

1. Determine the cable lengths, cut them to length
   • Use standardized distances to make measuring consistent.
   • Include excess length for all cables to allow for service relief and to make wiring the control box easier.
2. Wire the device connectors
   1. Identify the ground wire
      • In flat rainbow-colored cables, the ground wire is black, brown, green, or gray, and it is always on an outside edge.
      • Thermocouple cables always have exactly two wires, each with a distinctive color. The ground wire is either entirely red or red-striped. The other wire color indicates the type of thermocouple (yellow for Type K, blue for Type T).
   2. Attach molex pins and housing
      • Use the wire order tool (TL-WOT) to identify correct color order
      • All ribbon cables are wired with high force female molex pins except for:
        • Pressure sensor cables (excluding black/white/gray pressure sensor 30 PSI cables)
        • All Type-T Thermocouples

Route Cables

Orient yourself to the types of cables used and their general positions on the system before attaching any cables. Organization of cables is essential to making the routing easy and having an aesthetically pleasing result

1. Work with one cable type at a time
   • There are two incompatible types of cables: quiet and noisy. Keep incompatible cables separated as much as possible, especially over long stretches.
     • Quiet: Thermocouples, pressure sensors, thermistors, and actuators. These can be freely bundled together.
     • Noisy: Heaters and Solenoid valves. These can be bundled together also.
     • Join incompatible bundles only when necessary and separate them wherever possible.
2. Connect the cables to all devices before routing any of them.
3. Count the cables in a section and divide them into cable sleds by cable type.
   • Cable sleds keep bundles of related devices collected and orderly, and prevent tangling.
4. Before routing a cable, determine its optimal orientation, either "ground up" or "ground down."
   • • Switchbank wires are ground down.
     • AC2 wires are ground up.
     • AC1 wires are ground down.
     • Heater Controller wires are ground down.
     • DAQ wires are ground up.

Secure cables to the frame

1. Begin from the farthest devices first and work toward the control box.
   • Use frequent cable ties to bundle the cables into groups and cable mounts to secure them to the frame.
     • Space the cable ties as evenly as possible, with 1 to 2 inches between them.
     • Locate cable mounts strategically and as evenly as possible, with a 4 to 6 inch spacing.
   • As the harness advances toward each device, merge the device's cable into the outside of a compatible bundle, orienting it "ground up" or "ground down" as appropriate.
   • Be sure to reserve an adequate, uniform service relief, or slack, so the cable and connector will never suffer strain in use. Extra long strain relief is required for heaters, FTCs and VTCs because these devices must be moved in normal operation or for shipping. FTCs and VTCs need enough slack to lower them completely free of their coldfingers.

Certain cables are easily overlooked, especially when their devices may not be present. Route these cables as soon as possible so they can be merged gracefully into appropriate bundles.

1. Route the GR pressure sensor cables from the graphite reactors. The GR pressure sensors are not present at this point. Refer to the CEGS model to determine the correct cable orientation for the sensors. Provide sufficient and consistent strain relief.
   • Pay close attention to these sensor connector pin-outs as they do not follow Aeon conventions.
2. Route the MC Thermister when the harness reaches the measurement chamber.

   • Note: this sensor connector pin-out does not follow Aeon conventions.

3. Route all other pressure sensor cables
   • These sensors are in the upright position and require excessive strain relief before joining the bundle
     • Refer to the model to determine their positions if the sensors are not present
4. Route the backing and roughing valve cables (vB and vR) from the Low Vacuum fitting.
5. Route the LN Supply solenoid valve cables from the appropriate location on the CEGS Frame.
6. Route the frame ground wire from a convenient fitting hanger near the Control Box.
7. Merge the tGM thermocouples into the GR thermocouple bundle.
8. Route the LN overflow thermocouple from a central area on the table beneath the LN Manifolds. Leave at least six inches of the end free at the table top.
9. Route the LN and air manifold cables before the harness reaches their merge point.
   • Route the LN Manifold level sensor thermocouples at the same time.
   • Pay special attention to the proper "ground-up/down" orientation for the LN+air cables; it often differs from other same-colored cables, with which they may be bundled.

Organize the bundles as they pass through the opening in the back of the control box, maintaining "ground up/down" orientations while avoiding cross-overs and tangles.