Incoming Power Conductors

Conduit entry space is provided at the top and bottom of the MCC structure. The top plates (and closing plates in bottom, if present) are removable for convenience in wiring and cutting conduit openings). A hinged door or cover allows access to the main lug, main circuit breaker, or main switch compartment. In some cases, the horizontal wireway cover must be removed.

Optional, top-located pull boxes are available if additional wiring space is required.

• Incoming power wires must use conduit connections to enter the ArcBlok-equipped main circuit breaker unit.

• Top-feed MCC main circuit breaker units with ArcBlok 1200 include a required, 18 in., high pull box (see Top and Bottom Incoming Main Breakers with ArcBlok, View A).

• Conduit connection is required at the top plate of the pull box or on the bottom plate of the MCC structure for bottom feed mains (see Top and Bottom Incoming Main Breakers with ArcBlok, View B).

• Seal around incoming wires using duct seal putty at conduit connections where the wires enter the pull box or cable vault.

• Arcblok 2500 is only available in bottom-feed MCC units.

• Incoming power wires must use conduit connections on the bottom plate of the MCC structure to enter the ArcBlok-equipped main circuit breaker unit.

• Seal around incoming wires using duct seal putty at conduit connections where the wires enter the cable vault.

• Breaker wire terminals are located behind the ArcBlok lug cover which is accessible after removal of the cable vault cover (see Top and Bottom Incoming Main Breakers with ArcBlok, Views A and B).

  Top and Bottom Incoming Main Breakers with ArcBlok

  

• Verify all incoming wires are correctly installed in wire terminals and tightened to required torque values. Torque requirements are found on labels on the main device or on a separate label inside the unit.

• Replace the lug cover after completing wire installation and before reinstalling the cable vault cover.

All cables must be laced and secured prior to installing the cable vault front cover.

1. For lacing material, select a sisal or hemp rope with a minimum of 2500 pounds of pull strength (625 pounds working load). Apply tape to any frayed end of the rope before lacing cables.

2. Lace the cables from all phases together in one bundle with a continuous length of rope. The ArcBlok lug cover must be in place and fastened prior to lacing (see Cable Lacing, View A). Make sure interphase barriers are inserted in the grooves of the ArcBlok lug cover.

   Cable Lacing

   

3. Lacing will require two looping groups: an initial, lower group and a second group closer to the ArcBlok.

4. Attach one end of the rope to the lower side of one of the cables, (see Cable Lacing, View B).

5. After attaching the rope, make a loop in it and pull the loop around the entire cable bundle from behind. Pull the loose end of the rope through the loop.

6. Continue to pull the rope through the loop until the rope is tight. Make a second loop and pass behind the cables using the same procedure. Put the loose end of the rope through the loop and pull the loop tight. This completes the first loop group.

7. Start the second (upper) loop group by first pulling the rope around the cable bundle, then repeat the procedure described in step 6 for the upper loop group. The spacing between the upper and lower loop groups should be no less than 4 in. (102 mm) (see Cable Lacing, View C).

8. Ensure the cable bundles do not dislodge the interphase barriers from the grooves of the ArcBlok lug cover (see ArcBlok Interphase Barriers and Lug Cover Grooves).

9. After the entire cable bundle has been laced, tie the loose end of the rope securely to the upper loop group, then cut and tape the loose end to prevent fraying. Make sure the rope is not obstructing the cable vault front cover or rear panel damper flap.

10. While keeping the ArcBlok lug cover in place, remove all cover hardware.

    NOTE: Make sure the interphase barriers remain inserted into the grooves of the ArcBlok lug cover (see ArcBlok Interphase Barriers and Lug Cover Grooves).

    ArcBlok Interphase Barriers and Lug Cover Grooves

    

11. Place the cable vault front cover on top of the ArcBlok lug cover.

12. Install 3/8–16 Keps™ nuts and torque them to 20–23 lb-ft. (27–31 N•m).

    NOTE: These instructions are for bottom feed main breakers. For top feed breakers, reverse references to the “upper” and “lower” loop groups.

• Locate and terminate all conduit in the MCC enclosure in the “available conduit area” designated on the equipment drawing.

• The conduit area is available towards the front of the section inside the cable vault.

  1. Remove and retain the 10–32 size hardware securing the equipment breaker cover.

  2. Remove and retain the breaker cover.

     Removing Equipment Front Covers

     

  3. Remove and retain 10–32 size hardware securing the equipment lower front cover.

  4. Remove and retain the equipment lower front cover.

  5. Unplug the terminal block of the ArcBlok Event Indicator and put it on the right side of the cable vault. Do not disconnect wires from the terminal block.

  6. Remove and retain 1/4–20 size hardware securing the cable vault front cover.

  7. Remove and retain the cable vault front cover.

     NOTICE
     damage to event indicator Do not damage ArcBlok event indicator while installing or uninstalling the cable vault front cover. Call Schneider Electric Services if the event indicator is damaged. Failure to follow these instructions can result in equipment damage.

     Removing Cable Vault Front Cover

     

     DANGER
     hazard of electric shock, explosion, or arc flash Replace conduit closure plate after creating the conduit holes. Do not turn on power if conduit closure plate is not installed. Failure to follow these instructions will result in death or serious injury.

     • Remove and retain the conduit closure plate for reuse. The customer must create any holes necessary for conduit entering the bottom of the MCC. After creating the holes, reinstall the conduit closure plate (see Bottom-fed ArcBlok Main Bottom Conduit Closure Plate).

     Bottom-fed ArcBlok Main Bottom Conduit Closure Plate

     

  8. Pull the cables inside the cable vault and terminate them on the ArcBlok lugs shown in Lug Cross Section Showing Hole Placement. Torque all wire-binding screws to 842 lb–in. (95 N•m).

     NOTICE
     damage to phase barriers Do not apply excessive force to the phase barriers during cable installation. Damage to the phase barriers can occur. Call Schneider Electric Services if the phase barriers are damaged. Failure to follow these instructions can result in equipment damage.

     1. Use a proper insulation stripping tool to strip a length of insulation from the end of the cable sufficient to fit into the full length of the lug barrel. Be careful not to nick or ring the strands.

     2. Thoroughly clean aluminum cable contact surfaces with a wire brush, or scrub them with an abrasive cloth to remove oxides and foreign matter.

     3. Immediately apply an acceptable joint compound to the bare aluminum surfaces.

     4. Install the rear cables into the rear three-hole lug. Wire strip length: 3.875 in. (98 mm).

     5. Install the cables into the front six-hole lug. Wire strip length: 2.50 in. (64mm) for the rear three holes. Wire strip length: 1.375 in. (35 mm) for the front three holes.

     6. Screw any unused wire binding screws in completely. Screw in all wire binding screws without cables installed so they are not in the way of the Thermal Interface Module (TIM) (see TIM Sleeve).

        Lug Cross Section Showing Hole Placement

        

  9. Cable entry into the cable vault must use conduit connections installed on the conduit closure plate. The conduits must be sealed using duct seal putty.

  10. Install the Thermal Interface Module (TIM):

      1. Verify TIM mating surfaces and lugs are clean and undamaged. Clean with a dry, lint-free rag.

      2. Install one TIM per phase and neutral using 1/4-20 size captive screws as shown in TIM Sleeve. Slide the plastic sleeve around each TIM against the top of the phase barriers. Sleeve must be flush with the top of the phase barriers. Torque all six TIM screws in a star pattern to 60 lb-in. (6.8 Nm).

         NOTE: The TIM mounting screws are not completely removable.

         Thermal Interface Module (TIM) Installation

         

         TIM Sleeve

         

  11. Install the ArcBlok module front cover assembly to enclose the ArcBlok module using 1/4-20 size screws provided as shown in ArcBlok Front Cover Installation. Install the cover by aligning the four alignment pins in the cover with the holes in the module side plates. Fasten five screws on the top row and another five in the middle row of the front cover. Use the remaining five screws for the bottom row while installing the cable vault front cover as mentioned in step 13. Torque all ten screws on the front cover to 60 lb-in. (6.8 Nm).

      ArcBlok Front Cover Installation

      

      NOTICE
      damage to tape on thermal interface module (TIM) Do not damage the tape on the TIM during installation of the ArcBlok front cover during this step. Call Schneider Electric Services if cover assembly is damaged. Failure to follow these instructions can result in equipment damage.

      NOTICE
      damage to arcblok module front cover assembly Do not apply excessive force to the ArcBlok module front cover assembly during installation. Call Schneider Electric Services if cover assembly is damaged. Failure to follow these instructions can result in equipment damage.

  12. Install one heatsink per phase and neutral on the front surface of the TIM using 1/4-20 size captive screws as shown in ArcBlok Heat Sink Installation. Torque all six screws on the heatsink in a star pattern to 60 lb-in. (6.8 N•m).

      ArcBlok Heat Sink Installation

      

      CAUTION
      Risk of burns from hot surfaces or heatsinks Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices when working near heatsinks. See NFPA 70E, NOM-029-STPS or CSA Z462 or local equivalent. Failure to follow these instructions can result in injury or equipment damage.

  13. Install the thermal sensor (if used) as labeled per phase in the thermal sensor mounting clip available underneath the heatsink with the temperature probe towards the base of the heat sink as shown in Thermal Sensor Installation.

      NOTICE
      damage to sensor spring loaded probe Do not damage or let the sensor spring loaded probe tip out of place during the installation to avoid temperature data discrepancy. Call Schneider Electric Services if the sensor is damaged. Failure to follow these instructions can result in equipment damage.

      Thermal Sensor Installation

      

  14. Perform substeps:

      1. Reinstall the cable vault front cover using (15) 1/4-20 size screws retained in step 5 (see Reinstall Cable Vault Front Cover).

      2. Locate (5) 1/4-20, x 1 in. long screws from ArcBlok Module kit and install at the top edge of the cable vault front cover to fasten the ArcBlok front cover. Torque all screws on cable vault front cover to 60 lb-in. (6•8 Nm) (see Reinstall Cable Vault Front Cover).

         Reinstall Cable Vault Front Cover

         

         Cable Vault Front Cover Labels

         

         DANGER

         hazard of electric shock, explosion, or arc flash Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E or CSAZ462. This equipment must be installed and serviced by qualified electrical personnel. Read instruction bulletin and familiarize yourself with the equipment before installing, operating, servicing, or troubleshooting the equipment. Turn off all power supplying this equipment before working inside this cable vault. Always use a properly rated voltage sensing device to confirm power is off. Do not turn on power without this cover installed. Incident Energy levels greater than 1.2 cal/cm2 are present if cover is uninstalled. Replace all devices, doors, and covers before turning on power to this equipment. Apply torque to cable vault hardware to 60 lb-in. (6.8 N•m). Failure to follow these instructions will result in death or serious injury.

  15. Re-plug the terminal block of the ArcBlok Event Indicator removed in step 4.

  16. Make sure the ArcBlok Event Indicator plunger is pushed back as shown in ArcBlok Event Indicator.

      ArcBlok Event Indicator

      

  17. Reinstall the equipment front covers and breaker cover using 1/4–20 size hardware retained in steps 1 and 2.

Cable restraint is required on the line-side of the ArcBlok section. All cables must be laced and secured prior to installing the cable vault front cover.

1. Wrap cables using 1/2 in. (13 mm) diameter sisal rope or equivalent.

2. Lace the cables from all phases together in one bundle with a continuous length of rope.

3. Lacing requires two sets of looping groups: an entry loop group and a second loop group nearer to the ArcBlok.

4. Attach one end of the rope to on of the cables about 10 in. (254 mm) from the floor.

5. After attaching the rope, make a loop in it and pull the loop around the entire cable bundle from behind. Pull the loose end of the rope through the loop and continue to pull it until the rope is tight.

6. Make a second loop and pass behind the cables using the same procedure. Put the loose end of the rope through the loop and pull the loop tight. Repeat this step one additional time.

7. Start the second (upper) loop group by first pulling the rope around the cable bundle, then repeat the procedure described in step 6 for the upper loop group. The spacing between the upper and lower loop groups must be no more than 5 1/2 in. (139 mm). See Upper and Lower Loop Group Spacing.

   Upper and Lower Loop Group Spacing

   

8. After the entire cable bundle has been laced, tie the end of the rope securely to the looping groups, then cut and tape the end to prevent fraying. Make sure the rope is not obstructing the cable vault front cover, fuse disconnect switch wiring, or ArcBlok Event Indicator plunger.