Vacon 20, Complete User'S Manual

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vacon installation
3
3.2.7 Stripping lengths of motor and mains cables
Figure 3.31: Stripping of cables
Note! Strip also the plastic cover of the cables for 360 degree earthing. See Figures
3.17, 3.18 and 3.25.
3.2.8 Cable installation and the UL standards
To meet the UL (Underwriters Laboratories) regulations, a UL-approved copper ca-
ble with a minimum heat-resistance of +60 / 75 °C must be used.
Use Class 1 wire only.
The units are suitable for use on a circuit capable of delivering not more than 50,000
rms symmetrical amperes, 600V maximum, when protected by T and J Class fuses.
For MI4 without DC-choke, maximum short circuit current has to be not more than
2.3 kA, for MI5 without DC-choke, maximum short circuit current has to be not more
than 3.8 kA.
Integral solid state short circuit protection does not provide branch circuit protec-
tion. Branch circuit protection must be provided in accordance with the National
Electric Code and any additional local codes. Branch circuit protection provided by
fuses only.
Motor overload protection provided at 110% of full load current.
3.2.9 Cable and motor insulation checks
These checks can be performed as follows if motor or cable insulations are suspect-
ed to be faulty.
1. Motor cable insulation checks
Disconnect the motor cable from terminals U / T1, V / T2 and W / T3 of the frequency
converter and from the motor. Measure the insulation resistance of the motor cable
20 mm
35 mm
8 mm
Earth conductor
8 mm