1. SWITCHGEAR BIG GRAY BOXES SWITCHBOARD

4. Why Different Standards? ANSI vs UL

5. Standards Comparison

6. Standards Comparison (cont.)

7. Switchgear has Defined Short Time Withstand Ratings!
Comparison (cont.)
Switchgear has Defined Short Time Withstand Ratings!

8. “Practice” Comparison
Switchgear maintenance permitted (not required by standard).
Switchboard maintenance often not allowed.

9. Side View

10. Rear View

11. Insulated Case vs Molded Case

12. Old Vs New
Insulated Case UL IRON FRAME ANSI

13. Insulated Case vs Molded Case

14. Advantages of Insulated Case Vs Iron Frame
Smaller footprint
More reliable (Modular Design with Fewer Parts)
Higher interrupting ratings
Higher withstand ratings (30 Cycles)
Reduced maintenance
Electronic Trip Units
Field Installable Trip Units
Communications
Power monitoring (2.5% Accuracy)

15. Mechanical Construction
Breaker Frames
Small :
800A ANSI,
1200A UL,
1600A IEC
Medium :
800 to 3200A ANSI,
800 to 3000A UL,
800 to 4000A IEC
Large :
4000 to 5000A ANSI,
4000 to 6000A UL,
4000 to 6300A IEC

16. Organic Vs Iron Frame
The thermoset material of the organic case has several advantages:
Very strong and lightweight
Provides good insulation, isolation, and dielectric
Molded to support and hold internal parts with no adjustments
Fewer parts reduces complexity of assembly and maintenance

17. Organic Vs Iron Frame
This is animated. Click the left top image to show the mech installation on the housing. The organic housing is very strong and lightweight. It provides a solid mounting base for the mechanism.
Continue by clicking the top center image to show the moveable contact.
The molded areas on the housing support and hold the moveable contacts with no adjustments necessary. This makes it easier to build and more reliable to use.
The CTs also fit in molded supports.
The organic housing provides ridgidity and a mounting area for the fixed contacts.
Once the parts are installed and the housing halfs are joined together, the organic case provides good insulation, isolation and dielectric between phases and between phase and ground.
The crowning touch is the patended arc chutes at are specially designed to aid in the dissipation of the heat and pressure associated with the interruption of a 200,000 Amp fault.
The Organic case provides the strength, isolation, insulation, and dielectric necessary for the extremely high interrupting ratings and other features of the new Masterpact.

18. Display type A P H LCD ammeter LED Bargraph LCD All functions LCD

19. UL 891 Switchboards

20. Switchboards

21. Typical Switchboard Ratings
Switchboards
Typical Switchboard Ratings
5000 A Mains and Bus
1200 A and smaller group mounted
Greater than 1200A Individally mounted Fixed or Drawout
Front Connected
UL 891 Gear
UL 489 Breakers

23. “Hybred UL 891 Switchboards”
Mix Insulated Case and Molded Case
Individially mounted
Front Connected
Rear Connected
Individually mounted
Drawout
Fixed
Group Mounted and Drawout
Fusible and Circuit Breaker
No requirement for isolation or
Barriers

24. SWITCHGEAR BIG GRAY BOXES SWITCHBOARD