additions to ex isting installations and shall be marked.
Exception: Rear-mounted units connected to a vertical bus that is common to front-mounted units shall be permitted to have a C, B, A phase arrangement where properly identified.
(C) Minimum Wire-Bending Space. The minimum wire- bending space at the motor control center terminals and minimum gutter space shall be as required in Article 312.
(D) Spacings. Spacings between motor control center bus terminals and other bare metal parts shall not be less than specified in Table 430.97.
(E) Barriers. Barriers shall be placed in all service- entrance motor control centers to isolate service busbars and terminals from the remainder of the motor control center.
430.98 Marking.
(A) Motor Control Centers. Motor control centers shall be marked according to 110.21, and such marking shall be plainly visible after installation. Marking shall also include common power bus current rating and motor control center short-circuit rating.
(B) Motor Control Units. Motor control units in a motor control center shall comply with 430.8.
IX. Disconnecting Means
430.101 General. Part IX is intended to require discon necting means capable of disconnecting motors and con trollers from the circuit.
FPNNo. 1: See Figure 430.1.
FPN No. 2: See 110.22 for identification of disconnecting means.
430.102 Location.
(A) Controller. An individual disconnecting means shall be provided for each controller and shall disconnect the controller. The disconnecting means shall be located in sight from the controller location.
Exception No. 1: For motor circuits over 600 volts, nominal, a controller disconnecting means capable of being locked in the open position shall be permitted to be out of sight of the controller, provided the controller is marked with a warning label giving the location of the disconnecting means.
Exception No. 2: A single disconnecting means shall be permitted for a group of coordinated controllers that drive several parts of a single machine or piece of apparatus. The disconnecting means shall be
located in sight from the controllers, and both the
disconnecting means and the controllers shall be
located in sight from the machine or apparatus.
Table 430.97 Minimum Spacing Between Bare Metal Parts
Opposite Polarity Where
Mounted on the Same Surface
Nominal Voltage mm in.
Not over 125 volts, nominal 19.1 3A Not over 250 volts, nominal 31.8 1 lA Not over 600 volts, nominal 50.8 2
Opposite Polarity Where
Held Free in Air Live Parts to Ground
mm in. nun in.
12.7 Vi 12.7 '/2
19.1 % 12.7 '/2
25.4 1 25.4 1
Exception No. 3: The disconnecting means shall not be required to be in sight from valve actuator motor (VAM) assemblies containing the controller where such a location introduces additional or increased hazards to persons or property and conditions (a) and (b) are met.
(a) The valve actuator motor assembly is marked with a warning label giving the location of the disconnecting means.
(b) The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in