ABB MS132 - Functional Requirements for All Motor Branch Circuits

MANUAL MOTOR STARTER GUIDE
APRIL 19 63/ 80
7.4 Functional requirements for all motor branch circuits
The installation standards for North America require that each motor branch circuit contains electrical components
capable of meeting four functional requirements: a disconnect means, short-circuit and ground-fault protection, a
control means, and overload protection. This can be achieved of using either multiple components or a single device.
A detailed description of the functional branch requirements will be shown in the next chapter.
Functional branch
requirements
Components
Combination
Motor Con-
trollers
1. Disconnect
means
Fusible dis-
connect
switches
Non-fusible
disconnect
switches
Inverse-time
circuit-break-
ers
Molded case
switches
Manual mo-
tor starters
Combination Mo-
tor Controllers
+
UL 98
CSA C22.2
No.4
UL 98
CSA C22.2
No.4
UL 489
CSA C22.2
No.5
UL 489
CSA C22.2
No.5
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
2. Short-circuit
and ground-
fault protec-
tion
Fuses
Inverse-time
circuit-break-
ers
MMS only
when Type E
or F
Combination Mo-
tor Controllers
+
UL 248
CSA C22.2
No.248
UL 489
CSA C22.2
No.5
UL 60947-4-1
CSA C22.2
No.60947-4-1
3. Control
means
Contactors Softstarters
Variable fre-
quency
drives
Non-fusible
disconnect
switches
Manual mo-
tor starters
Combination Mo-
tor Controllers
+
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 508C
CSA C22.2
No.274
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
4. Overload
protection
Overload
relays
Universal
motor con-
trollers
Manual Motor
Starters
Combination Mo-
tor Controllers
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
1a. Local dis-
connect (if
required)
…or any
shown above
next to
1. disconnect
means
Non-fusible
disconnect
switches
Manual motor
starters
UL 60947-4-1
CSA C22.2
No.60947-4-1
UL 60947-4-1
CSA C22.2
No.60947-4-1
Table 25: Functional requirements for all motor branch circuits
The chart above shows a graphical representation of the functional requirements for all motor branch circuits. Man-
ual motor starters are capable of meeting all of the requirements listed above. However, in order for manual motor
starters to be used for short-circuit and ground-fault protection, they must be additionally certified as Type E or F
combination motor controllers.
M