Initial Maintenance

Follow the steps below at the time of installation to locate and tighten any connections that may have loosened during shipment and handling:

1. Turn off all power supplying this equipment before working on or inside the equipment, and follow lockout/tagout procedures. Always use a properly rated voltage sensing device to confirm power is off.

2. Remove the top and bottom horizontal wireway covers in each section.

3. Expose the bus and bus connections by removing the two-piece bus barrier in each section.

4. Examine all bus bars and connectors. Replace any parts that are badly discolored, corroded, pitted, or otherwise damaged.

5. Verify that all bolts at the bus connection points indicated by a hexagon in Typical Bus Connection Points are in place and properly tightened. Although one specific type of compartment or bus is shown in Typical Bus Connection Points, perform this maintenance on all bolted connections. See Bus Connection Torque Values for torque values.

6. Access to load-side connections for top-feed ArcBlok main sections will be restricted by the cable vault, so an access panel in the cable vault provides access to B phase bus connections. Bus connections for A and C phases are located at the outer edges of the cable vault. (See Typical Bus Connection Points—Top-Feed ArcBlok Main Access.)

   Typical Bus Connection Points

   Typical Top-Located 600 A or 800 A Main Lug Compartment
   Typical Splice Bar Connection	Typical Horizontal Bus Connection

   Typical Bus Connection Points—Top-Feed ArcBlok Main Access

   

   Main Lug Compartment Torque Connection

   

   Bus Connection Torque Values

   Bolted Connection Location	Torque Range
   Horizontal bus (all locations)	68–70 lb-ft (92.29–94.54 N•m)
   Horizontal ground bus (all locations)	5–6 lb-ft (6.75–8.44 N•m)
   Splice bars—0.375 in. diameter bolts	31–32 lb-ft (41.64–43.33 N•m)
   Splice bars—0.5 in. diameter bolts	68–70 lb-ft (92.29–94.54 N•m)

7. Verify that all main lug, circuit breaker, or fusible switch set screws holding incoming conductors in main lugs are in place and properly tightened (see Main Lug Compartment Torque Connection). Use a torque wrench and a 3/8 in. allen bit to torque the lug set screws to the appropriate value (see Cable Connection Torque Values).

8. Inspect all insulators, braces, and barriers; replace any that show signs of arcing damage, tracking, excessive heat, or cracking.