Mitsubishi Electronics 520 540 Air Conditioner User Manual


 
99
Current detection function
2
FUNCTIONS
2.5.2 Zero current detection (Pr. 50 , Pr. 51 )
<Setting>
Use Pr. 64 or Pr. 65 (output terminal function selection) to assign the terminal used for
Y13 signal output.
When the inverter's
output current falls
to "0[A]", torque will
not be generated.
This may cause a
gravity drop when
the inverter is used
in vertical lift
application.
To prevent this, the output current "zero" signal can be output from the inverter
to close the mechanical brake when the output current has fallen to "0[A]".
Parameter Name
Factory
Setting
Setting
Range
Remarks
50 Zero current detection level 5% 0 to 150%
Setting is enabled when
Pr. 30 = "1"
51 Zero current detection period 0.5s 0.05 to 1s
POINT
If the output is lower than the Pr. 50 setting for longer than the time set in Pr.
51 during inverter operation, the zero current detection (Y13) signal is output
from the inverter's open collector output terminal.
Parameter Description
50
Set the zero current detection level.
Set the level of zero current detection in terms of the percentage of the rated
inverter current from the output current value of 0 [A].
51
Set the zero current detection period.
Set a period of time from when the output current falls to or below the Pr. 50
setting to when the zero current detection signal (Y13) is output.
CAUTION
If the current falls below the preset detection level but the timing condition is
not satisfied, the zero current detection signal is held on for about 100ms.
Changing the terminal functions using Pr. 64 and Pr. 65 may affect the other
functions. Please make setting after confirming the function of each terminal.
Related parameters
Assignment of Y13 signal to terminal Pr. 64 "RUN terminal function selection", Pr. 65 "A, B, C
terminal function selection" (refer to page 111)
ON
Start signal
OFF
Pr.50
Pr.51
detection period
OFF OFF
100ms
ON ON
Pr.51
detection period
Pr.50
"zero
current
detection
level"
Output
current 0 [A]
Zero current
detection signal
output (Y13)