Mitsubishi Electric FR-A800, Instruction Manual

Page: 730 / 1042

(A) Application parameters Parameters
5 - 550
Operation setting at pre-charge fault
●
The protective function can be activated when limit values are exceeded if the time limit is set at
Pr. 764 "Pre-charge time limit" and the measured value limit level is set at Pr. 762 "Pre-charge
ending time".
●
Whether to shut off output immediately after the protective function is activated or after a
deceleration stop can be selected by Pr. 760 "Pre-charge fault selection".
●
When the time limit is exceeded, the Pre-charge time over (Y51) signal is output. When the
measured value limit level is exceeded, the Pre-charge level over (Y53) signal is output. For the
Y51 signal, set "51 (positive logic)" or "151 (negative logic)" to Pr. 190 to Pr. 196 (output terminal
function selection), and for the Y53 signal, set "53 (positive logic)" or "153 (negative logic)" in Pr.
190 to Pr. 196 (output terminal function selection) to assign the functions to terminals.
●
Example of protective function by time limit (Pr. 760 = "0")
NOTES When the PID output suspension (SLEEP) function is in use, and the X77 signal is set to valid after
this function is released, set the X77 signal to OFF after checking that the during pre-charge oper-
ation signal (Y49) is OFF.
When the PID output suspension (SLEEP) function is in use, and PID control is to be performed
immediately after this function is released, leave the X77 signal ON until PID control ends.
When the pre-charge operation is valid, the pre-charge operation is performed at the output shut-
off cancellation (MRS signal, etc.). (The pre-charge operation is also performed in the case of
instantaneous power failure when the automatic restart after instantaneous power failure is valid.)
When the control method is changed to PID control from a control with higher priority in fre-
quency command (multi-speed setting, Jog operation, etc.), the motor is accelerated/decelerated
until its speed reaches the automatic switchover frequency (Pr. 127), and the pre-charge is per-
formed.
NOTES For Pr. 764 "Pre-charge time limit", set a value greater than Pr. 762 "Pre-charge ending time".
For Pr. 763 "Pre-charge upper detection level", set a value greater than Pr. 761 "Pre-charge ending
level".
I002704E
Fig. 5-272: Reaching of pre-charge time limit
STF
Y49
Y51
ALM
E.PCH
Ending level
Measured value [PSI]
Pr. 761
Output frequency [Hz]
Pr. 764
When Pr. 760 = "0",
output is immediately shut off.
Time
Time
Pr. 127
0 Hz