TECO-Westinghouse PA7300 Series, Installation And Operation Manual

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(B) GROUNDING (Protective Earth)
Ground the PC Drive through ground terminal E (PE).
(1) Ground resistance should be 100 ohms or less.
(2) Never ground the AC Drive in common with welding machines, motors, other high-current
electrical equipment, or a ground pole. Run the ground lead in separate conduit from leads for
high-current electrical equipment.
(3) Use the ground leads which comply with AWG standards, and make the sure the length is as
short as possible.
(4) Where several PA7300 units are used side-by-side, it is preferable to ground each unit separately
to ground poles. However, connecting all the ground terminals of the PA7300 in parallel while
grounding only one of the PA7300s to the ground pole is also permissible (Fig. 3).
Be sure not to form a loop with the ground leads.
(a) (b) (c)
Fig 3. Grounding of Multiple PA7300 Drives
(C) CONTROL CIRCUIT
(1) Separation of control circuit leads and main circuit leads: All signal leads must be separated
from power leads L1 (R), L2 (S), L3 (T), +, - , B2, T1 (U), T2 (V), T3 (W) and other power cables
to prevent erroneous operation caused by noise interference.
(2) Control circuit leads R1A-R1B-R1C, R2A-R2C, and R3A-R3C (contact output) must be separated from
leads 1 to 8, A01, A02, D01-DCOM, and 24V, SC, 24VG,VIN, AIN, AUX, MT, GND.
(3) Use twisted shielded or twisted pair shielded wire for the control circuit line, and connect the
shield sheath to the AC Drive terminal E to prevent malfunctions caused by noise. See Fig.4.
Wiring distance should be less than 164ft (50m).
Fig. 4 Shielded Wire Termination
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PA 7300 PART I: INSTALLATION MANUAL