Yaskawa E7 Drive User Manual - Manual (Page 119)

Programming 5 - 45
L4 Speed Command Loss Detection
L4-01 Speed Agreement Detection Level
Setting Range: 0.0 to 200.0 Hz
Factory Default: 0.0 Hz
L4-02 Speed Agreement Detection Width
Setting Range: 0.0 to 20.0 Hz
Factory Default: 2.0 Hz
Parameters L4-01 and L4-02 are user specified levels for use with the Fref/Fout Agree 1, Fref/Set Agree 1, and Freq Detect
and 2 digital output functions. Please refer to the H2 Digital Output Parameters in the Programming Manual for more
information.
L4-05 Frequency Reference Loss Detection Selection
L4-06 Frequency Reference at Loss of Frequency Reference
Setting Range: 0.0 to 100.0% of previous speed command
Factory Default: 80.0% of previous speed command
The Drive can be configured to compensate for the loss of its external speed command. An external speed command is
considered lost if it drops 90% of its value in 400mS or less.
Fig 5.36 Loss of Frequency Reference Timing Diagram
To enable Frequency loss detection, set L4-05= “1: Enabled @ % of PrevRef”. If Frequency Reference Loss Detection is
enabled and the reference is lost, the Drive continues to operate at the speed commanded by parameter L4-06. When the speed
command returns, the Drive again follows the speed command.
Setting H2-01/H2-02= “C: Loss of Ref”, configures a digital output as a Frequency Reference Loss indication only when
L4-05= “1: Enabled @ % of PrevRef”.
Setting Description
0 Disabled
1 Enabled @ % of PrevRef (factory default)
t
Frequency
Reference
Output
Frequency t
10%
T
L4-06
100%
T = 400mS
100%
10%
TIME
TM_E7_01_07182008.book Page 45 Wednesday, July 23, 2008 2:35 PM