Hitachi SJ Series, User Manual

Page: 361 / 786

12-16-12
Chapter 12 Inverter Function
12.16.9 Detecting over-speed error
•
How to monitor whether the motor is rotating at
below the maximum speed
•
How to display an error signal when the allowable
speed of the system is exceeded
•
The over-speed error detection function judges
that the speed is excessive if the feedback speed
exceeds the over-speed level.
•
This function operates when other than "0.0" is
specified for [bb-80] Over-speed error detection
level.
■
Parameter
•
To use this function, speed feedback by the
encoder is required.
•
Whether the speed is excessive is determined
according to the feedback frequency displayed on
[dA-08] Detected frequency monitor.
•
When the speed has exceeded [bb-80]
Over-speed error detection level and [bb-81]
Over-speed error detection time has elapsed, it is
judged as an over-speed error.
•
When an over-speed error occurs, the inverter
trips with [E107] Over-speed error.
Item Parameter Data Description
Over-speed error
detection level setting
[bb-80] 0.0~150.0(%)
Sets the speed level at which the speed is
determined to be excessive.
Over-speed error
detection time
[bb-81] 0.0~5.0(s)
Sets the time to judge the speed to be an
error after it has excessively increased. The
inverter trips with [E107] Over-speed error.
Detected frequency
monitor
[dA-08]
-590.00~
590.00(Hz)
Displays the data obtained through encoder
feedback.
Q
A
！
Speed
bb-81
0
bb-80 bb-80
The inverter trips due to an
over-speed error.