E (Emergency Stop) Emergency Stop / Force Stop fault in Toshiba drive
E (Emergency Stop) Emergency Stop / Force Stop fault in Toshiba drive
Description This is technically not a hardware failure but a status trip. The drive has been commanded to stop immediately via an external safety circuit or a specific logic input assigned to "Emergency Stop." Unlike a standard stop which follows a deceleration ramp, an E-trip usually cuts output immediately (coast to stop) or slams the motor to a halt depending on configuration. Causes
1. External Button: An operator pressed the E-Stop mushroom button.
2. Broken Wire: The safety circuit (normally closed loop) has a loose wire or break, simulating a button press.
3. Logic Conflict: A PLC or automation system sent a contradictory command or a specific logical input programmed as "E" was triggered.
4. Panel Keypad: The Stop key on the keypad was pressed while the drive was in Remote/Terminal mode (if parameter settings allow this override). Solution This requires tracing the control wiring. Look at the drive's I/O terminals (often labeled CC, F, R, RES, S1, S2, etc.). Identify which terminal is assigned the "Emergency Stop" function in the parameters (often assigned to terminal RES or S3).
Most safety circuits are "Normally Closed" (NC) – meaning 24V must be present for the drive to run. If the wire breaks or the button is pressed, the 24V signal drops, triggering the E fault. Use a multimeter to check for 24V (or control voltage) at that terminal. If 0V is present, find the open switch in the field.
If the trip was caused by pressing the "STOP" button on the local keypad while the drive was in Remote Control, you have to cycle power or toggle the Reset command to clear it. To prevent this in the future, check the "Stop Key Priority" parameter. You can disable the local keypad stop button if the drive is strictly controlled by a PLC, though this is often discouraged for safety reasons. Always verify the mechanical safety of the machine before resetting an E-trip.
Description This is technically not a hardware failure but a status trip. The drive has been commanded to stop immediately via an external safety circuit or a specific logic input assigned to "Emergency Stop." Unlike a standard stop which follows a deceleration ramp, an E-trip usually cuts output immediately (coast to stop) or slams the motor to a halt depending on configuration. Causes
1. External Button: An operator pressed the E-Stop mushroom button.
2. Broken Wire: The safety circuit (normally closed loop) has a loose wire or break, simulating a button press.
3. Logic Conflict: A PLC or automation system sent a contradictory command or a specific logical input programmed as "E" was triggered.
4. Panel Keypad: The Stop key on the keypad was pressed while the drive was in Remote/Terminal mode (if parameter settings allow this override). Solution This requires tracing the control wiring. Look at the drive's I/O terminals (often labeled CC, F, R, RES, S1, S2, etc.). Identify which terminal is assigned the "Emergency Stop" function in the parameters (often assigned to terminal RES or S3).
Most safety circuits are "Normally Closed" (NC) – meaning 24V must be present for the drive to run. If the wire breaks or the button is pressed, the 24V signal drops, triggering the E fault. Use a multimeter to check for 24V (or control voltage) at that terminal. If 0V is present, find the open switch in the field.
If the trip was caused by pressing the "STOP" button on the local keypad while the drive was in Remote Control, you have to cycle power or toggle the Reset command to clear it. To prevent this in the future, check the "Stop Key Priority" parameter. You can disable the local keypad stop button if the drive is strictly controlled by a PLC, though this is often discouraged for safety reasons. Always verify the mechanical safety of the machine before resetting an E-trip.
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