Troubleshooting: Mechanical Control Operations

@writer: (confirmed 12/11/24) topic shared in Masterpact MTZ1 User Guide (DOCA0100), Masterpact MTZ2/3 User Guide (DOCA0101), and in the appendix in Masterpact MTZ End-user and Manufacturer Maintenance Procedures (DOCA0103 and DOCA0104). Any changes made will be made in all these guides.

Definition

Mechanical control operations are operations that are made using the opening or closing pushbuttons.

Device Cannot be Closed by Using the Mechanical Closing Pushbutton

Symptom	Probable causes	Solutions
The blue fault-trip reset button is popped out.	The blue fault-trip reset button has not been reset.	Clear the fault. Push the blue fault-trip reset button.
–	Device is padlocked or keylocked in the open position.	Unlock the device.
–	Device is interlocked mechanically in a mechanical interlocking system.	Check the position of the other device in the changeover system. Modify the situation to release the interlock.
The closing spring and ready-to-close indicator shows that the mechanism is discharged. .	Stored energy mechanism is not charged.	Charge the mechanism manually. If the device is equipped with an MCH gear motor, check the supply of power to the motor. If the problem persists, replace the MCH gear motor.
The closing spring and ready-to-close indicator shows that the mechanism is charged but the device is not ready to close.	MX opening voltage release is permanently powered.	As there is an opening order, determine the origin of the order. The order must be canceled before the device can be closed.
	MN undervoltage release is not powered due to an opening order.	As there is an opening order, determine the origin of the order. The order must be canceled before the device can be closed.
	MN undervoltage release is not powered due to insufficient voltage power supply.	Check the voltage and the MN supply circuit (V > 0.85 Un). If the problem persists, replace the MN undervoltage release.
Recurring undervoltage trip.	The measured voltage remains at 0 V.	Set the undervoltage behavior parameter, Vmin behavior, to Force to Off when CB is open. For more information, refer to DOCA0102•• MasterPacT MTZ - MicroLogic X Control Unit - User Guide in Related Documents at the beginning of this guide.
The position release button on the chassis of the drawout device is pushed in.	Device is not correctly connected.	Terminate racking in (connection) of the device, making sure that it is fully inserted in the chassis, to the connected position. Check that the position release button is popped out.

Device Cannot be Opened by Using the Mechanical Opening Pushbutton

Probable causes	Solutions
Operating mechanism incident or welded contacts.	Contact your Schneider Electric Services representative.