Toshiba Q-Flowsaver II - Manual (Page 18)

TOSHIBA
4.2 Selection of Main Circuit Wiring Equipment and
Standard Cable Sizes (cont'd)
* The customer supplied Molded Case Circuit Breaker (MCCB) or Magnetic Circuit
Protector (MCP) should be coordinated with the available short circuit current. The units
are rated for output short circuit faults of 5000A (1 - 50 HP), lO.OOOA (51 - 200 HP), and
18,000A (201 - 400 HP) according to the UL 508C "Power Conversion Equipment",
Table 58.2 or CSA Standard C22.2 No.14-M1987 "Industrial Control Equipment"
Table 24. The selection of breakers for this table is in accordance with 1990 NEC
Article 430. The selection of these breakers takes into consideration motor starting
at the low end of the output voltage specifications but does not consider the use of
high efficiency motors.
* For multiple motor applications, the magnetic only MCP should be replaced by a thermal
magnetic MCCB. The MCCB should be sized according to 1.25 X (largest motor Full
Load Amps) + (sum of all other motor Full Load Amps) to meet National Electric Code
(NEC) or Canadian Electrical Code (CEC) requirements. An individual overload relay
must be provided for each motor in multiple motor applications.
** Wire sizing is based upon NEC table 310-16 or CEC Table 2 using 75 deg C cable, an
ambient of 30deg C, cable runs for less than 200 FT., and copper wiring for not more
than three conductors in raceway or cable or earth (directly buried). The customer should
consult the NEC or CEC wire Tables for his own particular application and wire sizing.
** For cable runs greater than 200 FT. between the motor and inverter, consult the factory
before installing.
*** Use two parallel conductors instead of a single conductor (this will allow for the proper
wire bending radius within the cabinet). Use separate conduits for routing parallel
conductors. This prevents the need for conductor derating (see note 3 this page).
K Use separate conduits for routing incoming power, power
CAUTION
to motor, and control conductors. Use no more than three
power conductors and a ground conductor per conduit.
Notes:
1. ) Auxiliary relays used to switch inverter signals should be capable of switching
low current signals (i.e. 5mA).
2. ) The inverter has internal overload protection, but the Local, National, or
Canadian Electrical Codes may require external motor overload protection.
3. ) When wiring with parallel conductors, the conductors should be kept together in
phase sets with U1, VI, W1 in one conduit and parallel conductors U2, V2, W2
in another conduit. The ground conductor should be in one of these conduits.
4) Twisted pair wiring should be used for external meters connected to AM and FM
terminals.
4.3 Grounding
The inverter should be grounded in accordance with Article 250 of the National Electrical
Code or Section 10 of the Canadian Electrical Code, Part I and the grounding conductor
should be sized in accordance with NEC Table 250-95 or CEC, Part I Table 16.
!\ CAUTION
Conduit is not a suitable ground for the inverter.
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