User`s manual

3-7
3
Installation and wiring
3. Installation and wiring
(3) Wiring precautions
Before starting wiring, make sure that the charge lamp is completely off. Use caution
because the capacitor might still be charged with high voltage creating a hazardous
condition. About 10 minutes or more after power-off use a voltmeter or similar
instrument to check that no voltage remains across the (+) and (–) terminals on the
main circuit terminal block, and then start wiring.
1) Main power input terminals (L1, L2, L3)
• Use an earth leakage breaker (ELB) to protect circuit (wiring) between the power
supply and main power input terminals (L1, L2, or L3).
• Some earth leakage breakers may malfunction due to effects from higher
harmonics, so use one having large current sensitivity at high frequencies.
• Connect an electromagnetic contactor that shuts off the power supply to the robot
driver to prevent a failure or accident from spreading when the robot driver's
protective function is activated.
• Do not attempt to start or stop the robot driver by turning on or off each
electromagnetic contactor provided on the primary side and secondary side of the
robot driver.
• Do not use the robot driver in an open-phase condition.
• Any of the following conditions may damage the converter module so use caution.
The power supply voltage imbalance is 3% or more.
The power supply capacity is 10 times larger than the robot driver capacity or
500kVA or more.
A sudden fluctuation occurs in the power supply.
(Example) Multiple robot drivers are connected to each other by a short bus
line.
In any case, connecting a DC reactor (DCL) is recommended.
• When turning power on or off allow at least a 5-minute time interval between
power on and off in order to avoid damage to the robot driver.
2) Motor cable connection terminals (U, V, W)
• To minimize voltage drops, use thicker wires than normally used.
3) DC reactor (DCL) connection terminals ( (+)1, (+) )
• These terminals are used to connect a DC reactor DCL for power factor
improvement.
A shorting bar is connected across terminals (+)1 and (+) at the factory prior to
shipping. When connecting a DC reactor to these terminals, disconnect the
shorting bar. When not using a DC reactor, leave the shorting bar connected.