Hach sc200 - Examining the Enclosure; Figure 69: Typical Bus Connection Points; Maintaining Bus Bars and Incoming Line Compartments; Section 6-Maintaining the MCC

80459-641-01E Model 6 Motor Control Centers
10/2012 Section 6—Maintaining the MCC
© 1999–2012 Schneider Electric All Rights Reserved
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ENGLISH
Section 6—Maintaining the
MCC
Before energizing any new MCC equipment, perform the maintenance
described in this section. Perform regular maintenance at least annually, or
more frequently if indicated by service conditions and your established
maintenance policy. Also perform maintenance following any service
interruption, electrical fault, or unusual occurrence.
Examining the Enclosure Examine the interior and exterior of the MCC for moisture, oil, or other
foreign material. Eliminate all foreign material and clean the MCC.
Clean the interior and exterior of the MCC with a vacuum cleaner. (Do not
use compressed air; it will redistribute contaminants to other surfaces.)
Check the enclosure for damage that might reduce electrical clearances.
Examine the finish of the enclosure. Touch up the paint if necessary.
Replace any badly corroded or damaged enclosure parts.
Maintaining Bus Bars and
Incoming Line Compartments
Perform maintenance of bus and incoming line lug connections at least
annually, or more frequently if indicated by service conditions and your
established maintenance policy. 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 wire trough 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, or pitted. Also replace parts subjected to
excessive temperatures.
5. Verify that all bolts at the bus connection points indicated by a hexagon
in Figure 69 are in place and properly tightened. Although one specific
type of compartment or bus is shown in Figure 69, perform this
maintenance on all bolted connections. See Table 6 for torque values.
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
CSA Z462.
• This equipment must only be installed and
serviced by qualified electrical personnel.
• Turn off all power supplying this equipment
before working on or inside equipment.
• Always use a properly rated voltage sensing
device to confirm power is off.
• Replace all devices, doors, and covers
before turning on power to this equipment.
Failure to follow this instruction will result
in death or serious injury.
NOTIC
E
HAZARD OF EQUIPMENT DAMAGE
• Never brush or use sandpaper on the bus;
doing so will remove plating and cause
oxidation. Use a cleaning fluid approved for
such use. Do not use cleaning fluid on
insulators.
• Do not attempt to clean bus bars or
connectors that are damaged in any way.
Replace them with new parts.
Failure to follow this instruction can result
in equipment damage.
Table 6: Bus Connection Torque Values
Bolted Connection Location Torque Range
Horizontal bus (all locations) 68–70 lb-ft (92.29–94.54 N•m)
Splice bars—0.375 in. diameter bolts 31–32 lb-ft (41.64–43.33 N•m)
Horizontal ground bus (all locations) 5–6 lb-ft (6.75–8.44 N•m)
Figure 69: Typical Bus Connection Points
AØ
AØ
BØ
CØ
AØ
BØ
CØ
BØ CØ
Typical Top-Located 600 A or 800 A Main Lug Compartment
Typical Splice Bar Connection Typical Horizontal Bus Connection
Splice bar