Mitsubishi Electric FR-D720S SC EC, Instruction Manual

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Troubleshooting Causes and corrective actions
FR-D700 SC EC 7 - 7
Operation Panel
Indication
PS
FR-PU04
FR-PU07
PS
Name PU Stop
Description
Stop with the STOP/RESET key of the PU is set in Pr. 75 "Reset selection/disconnected
PU detection/PU stop selection". (For Pr. 75, refer to section 6.16.1.)
Check point Check for a stop made by pressing the STOP/RESET key of the operation panel.
Corrective action Turn the start signal off and release with PU/EXT key.
Operation Panel
Indication
RB
FR-PU04
FR-PU07
RB
Name Regenerative brake prealarm
Description
Appears if the regenerative brake duty reaches or exceeds 85% of the Pr. 70 "Special
regenerative brake duty" value. When the setting of Pr. 70 "Special regenerative brake
duty" is the initial value (Pr. 70 = 0), this warning does not occur.
If the regenerative brake duty reaches 100%, a regenerative overvoltage (E. OV ) occurs.
The RBP signal can be simultaneously output with the [RB] display. For the terminal used
for the RBP signal output, assign the function by setting "7 (positive logic) or 107 (negative
logic)" in any of Pr. 190, Pr. 192 or Pr. 197 "Output terminal function selection". (Refer to
section 6.9.5.)
Check point
Check that the brake resistor duty is not high.
Check that the Pr. 30 "Regenerative function selection" and Pr. 70 "Special regenerative
brake duty" values are correct.
Corrective action
Increase the deceleration time (Pr. 8).
Check the Pr. 30 "Regenerative function selection" and Pr. 70 "Special regenerative
brake duty" values.
Operation Panel
Indication
TH
FR-PU04
FR-PU07
TH
Name Electronic thermal relay function prealarm
Description
Appears if the cumulative value of the Pr. 9 "Electronic thermal O/L relay" reaches or
exceeds 85% of the preset level. If it reaches 100% of the Pr. 9 "Electronic thermal O/L
relay" setting, a motor overload trip (E. THM) occurs. The THP signal can be simultane-
ously output with the [TH] display. For the terminal used for THP signal output, assign the
function by setting "8 (positive logic) or 108 (negative logic)" in any of Pr. 190, Pr. 192 or
Pr. 197 "Output terminal function selection"). (Refer to section 6.9.5.)
Check point
Check for large load or sudden acceleration.
Is the Pr. 9 "Electronic thermal O/L relay" setting is appropriate? (Refer to section 6.7.1.)
Corrective action
Reduce the load weight or the number of operation times.
Set an appropriate value in Pr. 9 "Electronic thermal O/L relay". (Refer to section 6.7.1.)
Operation Panel
Indication
MT
FR-PU04
FR-PU07
—
Name Maintenance signal output
Description
Indicates that the cumulative energization time of the inverter has reached a given time.
When the setting of Pr. 504 "Maintenance timer alarm output" set time is the initial value
(Pr. 504 = 9999), this warning does not occur.
Check point
The Pr. 503 "Maintenance timer" setting is larger than the Pr. 504 "Maintenance timer
alarm output set time" setting. (Refer to section 6.20.3.)
Corrective action Setting "0" in Pr. 503 "Maintenance timer" erases the signal.