BENSHAW RediStart MX3 Series, User Manual

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Wiring Considerations
3.4
Wiring Considerations
3.4.1 Wiring Practices
When making power and control signal connections, the following should be observed:
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Never connect input AC power to the motor output terminals T1/U, T2/V, or T3/W.
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Power wiring to the motor must have the maximum possible separation from all other wiring. Do not run control wiring in the same
conduit; this separation reduces the possibility of coupling electrical noise between circuits. Minimum spacing between metallic
conduits containing different wire groups should be three inches (8cm).
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Minimum spacing between different wiring groups in the same tray should be six inches.
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Wire runs outside an enclosure should be run in metallic conduit or have shielding/armor with equivalent attenuation.
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Whenever power and control wiring cross it should be at a 90 degrees angle.
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Different wire groups should be run in separate conduits.
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With a reversing application, the starter must be installed in front of the reversing contactors.
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NOTE: Local electrical codes must be adhered to for all wiring practices.
3.4.2 Considerations for Control and Power Wiring
Control wiring refers to wires connected to the control terminal strip that normally carry 24V to 115V and Power wiring refers to wires
connected to the line and load terminals that normally carries 200VAC - 600VAC respectively. Select power wiring as follows:
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Use only UL or CSA recognized wire.
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Wire voltage rating must be a minimum of 300V for 230VAC systems and 600V (Class 1 wire) for 460VAC and 600VAC systems.
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Grounding must be in accordance with NEC, CEC or local codes. If multiple starters are installed near each other, each must be
connected to ground. Take care to not form a ground loop. The grounds should be connected in a STAR configuration.
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Wire must be made of copper and rated 60/75°C for units 124 Amps and below. Larger amp units may use copper or aluminum wire.
Refer to NEC table 310-16 or local codes for proper wire selection.
3.4.3 Considerations for Signal Wiring
Signal wiring refers to the wires connected to the control terminal strip that are low voltage signals, below 15V.
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Shielded wire is recommended to prevent electrical noise interference from causing improper operation or nuisance tripping.
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Signal wire rating should carry as high of a voltage rating as possible, normally at least 300V.
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Routing of signal wire is important to keep as far away from control and power wiring as possible.
3.4.4 Meggering a Motor
If the motor needs to be meggered, remove the motor leads from the starter before conducting the test. Failure to comply may damage the
SCRs and WILL damage the control board, which WILL NOT be replaced under warranty.
3.4.5 High Pot Testing
If the starter needs to be high pot tested, perform a DC high pot test. The maximum high point voltage must not exceed 2.0 times rated
RMS v 1000VAC (High pot to 75% of Factory). Failure to comply WILL damage the control board, which WILL NOT be
replaced under warranty. An example to find the high point voltage is (2.0 * rated RMS v 1000) * 0.75.
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3 - INSTALLATION