Yaskawa E7B Drive Bypass - Manual (Page 168)

Programming 5 - 74
L8-11 Heatsink Cooling Fan Operation Delay Time
Setting Range: 0 to 300 Seconds
Factory Default: 300 Seconds
Parameters L8-10 and L8-11 allow the Drive programmer to customize the heatsink cooling fan operation. Parameter L8-10
determines whether the cooling fans are always ON whenever the Drive is powered (L8-10= “1: Fan Always On”) or if the
cooling fans are only ON when the Drive is in a Run condition (L8-10= “0: Fan On-Run Mode”).
Parameter L8-11 is a delayed OFF for the cooling fan if L8-10= “0: Fan On-Run Mode”. When the cooling fans are set to turn
OFF when the Run command is removed, parameter L8-11 will cause the fans to continue cooling the Drive for the amount of
time programmed into L8-11 after the Run command is actually removed. The Drive can be programmed to allow the cooling fan
to run for up to 5 minutes (factory default) after the run command is removed.
Both parameters are intended to extend fan life while still providing sufficient cooling for proper Drive operation.
Fig 5.38 Heatsink Cooling Fan Operation Timing Diagram
L8-19 Overheat Frequency Reference Reduction Level
Setting Range: 0.0 to 100.0% of maximum frequency
Factory Default: 20.0% of maximum frequency
When the heatsink temperature reaches the OH Pre-alarm level (L8-02) and the Overheat Pre-Alarm Operation Selection
parameter is set for Alarm and Reduce (L8-03= “4: OH Alarm & Reduce”), the L8-19 parameter sets the amount of speed
decrease that will be applied to the Speed Command in order to lower the heatsink temperature. The decrease in speed will
lower the current being switched and conducted by the heat producing output transistors of the Drive.
Parameter L8-19 is set in percentage of maximum frequency (E1-04).
t
t
Run
Command
Heatsink Fan
RUN
L8-11
ON (CLOSED)
OFF (OPEN)
OFF (OPEN)
ON (CLOSED)
TIME