Caution, Toshiba, 3 communication group parameters – Toshiba Q-Flowsaver II User Manual

Page 46

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TOSHIBA

9.3

COMMUNICATION GROUP PARAMETERS

AUTOMATIC RESTART AFTER INSTANTANEOUS POWER FAILURE SELECTION

(ITEM 1) - Use this function to select auto-restart on or off. When selected, the inverter

will automatically restart into a free-rotating motor. This restart will occur only after an

instantaneous power interruption has occurred. The function allows the inverter to

sample the speed of the free-rotating motor at the end of the interruption and output a

matching frequency when power is reapplied. This assures smooth restarts of a free-

running motor when an instantaneous power loss has occurred such as when the

system is switched from a commercial bypass run to an inverter run.

AUTOMATIC RESET SELECTION (ITEM 2) - When this function is selected, the inverter

will automatically try to reset itself and restart the motor when a protective function

activates fault trip. The following chart shows the auto-reset procedure for over-current

and over-voltage fault trips.

AUTO RESET CONDITIONS

Cause of fault

Reset Process

Reset Failure Conditions

Overcurrent

Overload

Tries to restart 5 times In succession

1st restart: 1 sec. after problem occurs.

2nd restart: 2 sec. after 1st restart.
3rd restart: 4 sec. after 2nd restart.
4th restart: 8 sec. after 3rd restart.
5th restart: 16 sec. after 4th restart.

The reset process follows this chart

unless a fault, other than those listed,
occurs. If this happens the Inverter will
not try to reset.

Overvoltage

Trips, displays OP, sets fault relay until
overvoltage condition Is removed.

Fault relay will be cleared after reset.

If the inverter is able to reach the original operating speed where the trip occurred, while

trying to restart, then the reset process counter resets to zero. The process now begins

again from 1st restart even if the original overcurrent condition still exists. While

preparing for a reset, the auto-reset function causes the fault code "0.0" to be displayed

alternately on the monitor display. Fault detection signals are not output during the

reset process. If the cause of the failure has not been corrected, then the intervals

before each attempted reset will be prolonged (See above chart).

If the load exhibits

an extremely large amount of inertia, automatic restart using the above procedure
may not work.

No restart is tried when any of the following messages are displayed:

"OCA" Overcurrent (transistor short-circuit at start-up)

Overcurrent (load end short-circuit at startup)

Ground fault

Emergency stop

"OCL"

"EF"

II ^11

"EEP"

EEPROM failure

CAUTION

Before using the automatic reset function, check to be
certain that the auto-reset procedure wiil not damage or
otherwise cause probiems for the toad equipment when the
restart operations are being executed.

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