EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
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Switching from commercial-power operation to inverter operation ISW50/ISW60: OFF ON<br />
(1) The inverter primary circuit SW52-1 is turned ON immediately.<br />
(2) The commercial power circuit SW88 is turned OFF immediately.<br />
(3) After an elapse of t2 (0.2 sec + time required for the main circuit to get ready) from when SW52-1 is turned ON,<br />
the inverter secondary circuit SW52-2 is turned ON.<br />
(4) After an elapse of t3 (0.2 sec + time specified by H13) from when SW52-2 is turned ON, the inverter<br />
synchronizes once the motor that has been freed from the commercial power to the commercial power<br />
frequency. Then the motor returns to the operation driven by the inverter.<br />
t1: 0.2 sec + Time specified by H13 (Restart mode after momentary power failure)<br />
t2: 0.2 sec + Time required for the main circuit to get ready<br />
t3: 0.2 sec + Time specified by H13 (Restart mode after momentary power failure)<br />
Selection of Commercial Power Switching Sequence<br />
J22 specifies whether or not to automatically switch to commercial-power operation when an inverter alarm<br />
occurs.<br />
Data for J22<br />
Sequence (upon occurrence of an alarm)<br />
0 Keep inverter-operation (Stop due to alarm.)<br />
1 Automatically switch to commercial-power operation<br />
• The sequence operates normally also even when SW52-1 is not used and the main power of the<br />
inverter is supplied at all times.<br />
• Using SW52-1 requires connecting the input terminals [R0] and [T0] for an auxiliary control power.<br />
Without the connection, turning SW52-1 OFF loses also the control power.<br />
• The sequence operates normally even if an alarm occurs in the inverter except when the inverter itself<br />
is broken. Therefore, for a critical facility, be sure to install an emergency switching circuit outside the<br />
inverter.<br />
• Turning ON both the magnetic contactor MC (88) at the commercial-power side and the MC (52-2) at<br />
the inverter output side at the same time supplies main power mistakenly from the output (secondary)<br />
side of the inverter, which may damage the inverter. To prevent it, be sure to set up an interlocking logic<br />
outside the inverter.<br />
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