VFD68 Variable Frequency Drives
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3.
Use Figure 12 to determine the maximum recommended wiring length for the VFD68 drive.
Note:
If the maximum wire length needs to be extended, select a larger wire size and recalculate the
maximum wire length.
Do not exceed 100 m.
Note:
Maximum wiring length is also affected by the setting of P. 72. See
Example:
Given a VFD66BGG-2C model, what is the maximum wiring length?
a.
Table 1 on page 6 indicates that a VFD66BGG-2C model is a 230 VAC drive, rated for 1.49 kW (2 HP).
b.
The rating information plate (Figure 1 on page 6) for that model indicates that the VFD66BGG drive
has a voltage rating of 230 VAC and a maximum output rating of 7 amperes.
c.
Table 19 on page 21 gives the recommended wire size as 14 AWG.
d.
Table 22 on page 22 shows 14 AWG size wire as having an electrical resistance of 8.28 milliohms/
meter.
e.
Using the equation in Figure 12 on page 23 and using the values we found in the preceding steps:
(11.5 * 230) / (7 * 8.28) = 2656.6 / 57.96 = 45.8
The maximum wire length is 45.8 meters.
Figure 12: Maximum Wire Length Calculation
V = Voltage rating (230 or 460 VAC)
I = Maximum output current (Amps)
R = Electrical resistance of the wire
(milliohms/meter)
Maximum Wire Length =
(11.55 * V)
(I * R)
