Toshiba H9 User Manual
Page 257
H9 ASD Installation and Operation Manual
249
*OP
Overvoltage
DC bus voltage exceeds
specifications.
• ASD attempting to start into a spinning motor after a
momentary power loss.
• Incoming commercial power is above the specified
range.
• Decel time is too short.
• Voltage spikes at the 3-phase input; install inductive
filter.
• DBR required.
• DBR resistance value is too high.
• DBR function is turned off.
• Overvoltage Stall feature is turned off.
• System is regenerating.
• Load instability.
• Disable the Ridethrough function (
).
OT
Overtorque
Torque requirement is in excess
of the setting of
for a time longer than the setting
of
.
• ASD is not correctly matched to the application.
•
setting is too low.
• Obstructed load.
*POFF
Control
Undervoltage
Undervoltage condition at the 5,
15, or the 24 VDC supply.
• Defective Control board.
• Excessive load on power supply.
• Low input voltage.
PtSt
Reference Point
Two speed-reference frequency
setpoint values are too close to
each other.
• Two speed reference frequency setpoints are too close to
each other (increase the difference).
UC
Undercurrent
With the Low-current Trip
(
) parameter enabled, the
output current of the ASD is
below the level defined at
and remains there for a time
longer than the setting of
this function sets the low-current trip threshold
* Reset ignored if active.
LED
Display
LCD
Display
Description
Possible Causes