The International & North American standards

1. 1
 Merlin Gerin  Square D  Telemecanique
The International & North American standards
MOE - Presentation 8th Oct

2. MOE - Presentation 8th Oct
The international &
american standards Content
 presentation of the standards
 the test sequences

3. MOE - Presentation 8th Oct
The international &
american standards Content
 presentation of the standards
• the standard influences
• the North American standards
• the international standard
• standard comparison
 generalities on the tests

4. MOE - Presentation 8th Oct
The international &
american standards The standard influences
IEC
IEC
IEC
IEC
IEC
JIS
CSA
UL
UL
IEC
IEC

5. MOE - Presentation 8th Oct
The international &
american standards The North-American standards
general rules
codes NEC (National Electrical Code)
publisher : NFPA (National Fire Protection Association)
guides recommandations CEE
"product" standards
ANSI UL NEMA

6. MOE - Presentation 8th Oct
The international &
american standards The international standard
general rules
codes regionals & nationals (Cenelec, VDE, NF,...)
guides national (C 15-100, ...)
"product" standards
IEC
International Electrotechnical Commission :
more than 40 country representatives,
institutional users, manufacturers

7. MOE - Presentation 8th Oct
The international &
american standards The international standard
IEC # previous
publication #
general rules 947-1 without equivalence
circuit breakers 947-2 157-1
switches 947-3
disconnectors
switches / disconnectors 408
combined-fuses
contactors and starters 947-4 158-1 & 292-2
switching devices 947-5 337
for control circuit
multiple function 947-6 without equivalence
connection devices
part 1 : automatic transfer
connection equipment
accessories 947-7 without equivalence

8. MOE - Presentation 8th Oct
The international &
american standards Standard comparison
combined test overload + endurance
short-circuit on Z sequence
single phase
temperature rise temperature rise temperature rise temperature rise
limited at 80° limited at 50°C limited at 50°C
(linked to the
evolution of technologies)
insulation impulse voltage creepage distance creepage distance
label of quality no UL listed materials id. UL
(manufacturer follow-up id. UL
standard)
IEC 947-2IEC 947-2 UL 489UL 489 ANSI 37-50 (PCB)ANSI 37-50 (PCB)

9. MOE - Presentation 8th Oct
The international &
american standards Presentation of the standards
conclusion
 UL & IEC standards are historically and culturally based on
different approaches : there are not to be compared
 UL & IEC standards guaranty the same level of safety for the
end user
 UL & IEC standards have the same level of constraints

10. MOE - Presentation 8th Oct
The international &
american standards Content
 presentation of the standards
 the test sequences
• generalities on the tests
• the sequences of the UL 489
• the sequences of theANSI C 37-50
• the sequences of the IEC 947-2

11. MOE - Presentation 8th Oct
The international &
american standards generalities on the tests
two types of test :
 type test
 routine test
general principle applied on type test whatever the
standard :
 calibration
 main tests : overload, short-circuit
 final checks : dielectric, tripping

12. MOE - Presentation 8th Oct
The international &
american standards Test sequence IEC 947-2
I all calibration of release
general dielectric withstand
performance mechanical / electrical endurance
overload (6 In)
dielectric withstand
verification temperature rise
trip-out (1.45 In)
II all rated service S/C breaking capacity (O-C0-CO)
Ics dielectric withstand
verification of temperature rise
trip-out (1,45 In)
III A calibration of release (2 Ir pole / pole)
and rated ultimate S/C breaking capacity (O-CO)
Icu B dielectric withstand
trip-out (2,5 In)
test type test
séq. breaker description

13. MOE - Presentation 8th Oct
The international &
american standards Test sequence IEC 947-2
IV B calibration of release (2 Ir pole / pole)
rated short-time withstand current
Icw verification of temperature rise (80°C at connections)
S/C breaking capacity max. short time withstand current (Icw)
dielectric trip-out (2 In)
combined B calibration of releases (2 Ir pole / pole)
rated short-time withstand current
Ics rated service S/C breaking capacity (O-CO-CO)
Icw dielectric withstand
verification temperature rise (80°C)
trip-out (1,45 In)
test type test
séq. breaker description

14. MOE - Presentation 8th Oct
The international &
american standards The IEC 947-2 & the breaker categories
the IEC defines 2 categories of circuit breakers
 Category A : not specifically designed for discrimination under
short circuit conditions
 Category B : specifically designed for discrimination under
short circuit conditions, with an intentional time delay
category B circuit breakers have an additional characteristic :
short time rating : Icw (in KA associated with time)
Icw values: CB < 2500A, Icw above 12 In or 5KA
CB > 2500A, Icw above 30KA

15. MOE - Presentation 8th Oct
The international &
american standards The circuit breaker , a multi-function
safety device ruled by IEC947-2
 more safety by Short Circuit breaking capacities,
that are close to the reallity.
 more safety for maintenance operation by the
disconnection function
 more continuity of service and dependability, by
the recongnition of coordination between two
breaker

16. MOE - Presentation 8th Oct
The international &
american standards a clarification of the breaking capacity
 the Ultimate breaking capacity (Icu)
- the characteristic to be taken into account, and compared to the
prospective short circuit level (3 phases bolted short circuit) for the
design of an installation
- Icu (kA) represents the maximum fault that the breaker can clear
- Icu test = O - CO sequence
 the Service breaking capacity (Ics)
- expresses the ability of the device to eliminate safely short circuits
with a greater likhood of occuring.
- Ics is given as a % of Icu
- Ics test = O - CO - CO, plus service conditions after breaking

17. MOE - Presentation 8th Oct
The international &
american standards the disconnection function
 the disconnection capacity of a circuit breaker is
garanteed by 3 test for a maximum of safety :
- shock wave voltage strength (Uimp = 12.3 kV)
- maximum leakage current under 110% Un
- mechanical test on the handle
 the identification by a specific symbol

18. MOE - Presentation 8th Oct
The international &
american standards the disconnection function
 the disconnection capacity of a circuit breaker is
garanteed by 3 test for a maximum of safety :
- shock wave voltage strength (Uimp = 12.3 kV)
- maximum leakage current under 110% Un
- mechanical test on the handle
 the identification by a specific symbol
"circuit breaker - disconnector"

19. MOE - Presentation 8th Oct
The international &
american standards
 discrimination, for a maximum of continuity of
service
only the breaker just above the fault trips
 cascading, for substantial savings
the breaking capacity of C2 can be less than the prospective
Isc, but the above breaker C1 will "help" for any short circuit
value between Icu2 and Isc
Co-ordination between circuit breaker