Key points and principle analysis of time parameter settings for European wire rope electric hoists

The European wire rope electric hoist achieves efficient and safe material handling through precise time parameter control. Its core time parameter setting is closely related to the working principle, as follows:

1、 Key Points for Setting Critical Time Parameters

Start delay (t2)

Function: To avoid load shock caused by switching directly to fast start.

Suggestion for setting: Adjust according to the recommended values of the device manufacturer, usually set in the control system parameter interface. For example, DEMAG's sixth generation DR electric hoist achieves precise control of start-up delay through frequency conversion+PLC technology, ensuring smooth acceleration.

Pre magnetization time (t3)

Function: Ensure that the motor receives sufficient magnetic field support during startup to achieve smooth starting.

Suggestion for setting: Set according to the manufacturer's recommended values and fine tune according to the load characteristics during actual operation. For example, the KONECRANES CXT electric hoist uses a dual winding variable pole dual speed motor, and its pre magnetization time needs to match the motor characteristics.

Demagnetization time (t4)

Function: To prevent the phenomenon of "slipping hook" during motor deceleration and braking.

Suggestion for setting: Set according to the motor deceleration characteristics and load inertia. For example, the STAHL AS electric hoist adopts a dual winding variable pole dual speed motor for the first time, and its demagnetization time needs to be adjusted in conjunction with the reducer (such as a planetary reducer).

Braking time (ts) and deceleration ramp time

Function: Ensure that the motor stops smoothly within the specified time to avoid impact.

Suggested settings:

The braking time is set according to the braking performance and load situation of the motor, ensuring that the brake ring on the brake wheel can be tightened in a timely manner after power failure.

The deceleration ramp time is set according to the load inertia and deceleration requirements to avoid excessive impact on the motor during deceleration. For example, the Demag DR electric hoist adopts electronic digitization and infrared remote monitoring technology, which can accurately adjust the deceleration slope time.

2、 The synergistic effect of working principle and time parameters

Start-up phase

After the start-up delay (t2), the motor is powered on, and the axial magnetic pulling force generated by the conical rotor overcomes the spring thrust, causing the rotor to move axially. The brake ring on the brake wheel disengages from the brake end cover, and the motor begins to rotate.

The pre magnetization time (t3) ensures that the motor obtains sufficient magnetic field at the moment of starting to avoid shaking.

runtime

The motor transmits torque to the lifting gear through the gearbox, driving the winch hook and wire rope to lift or lower heavy objects.

Variable frequency technology dynamically adjusts motor speed based on load requirements to optimize operational efficiency. For example, the Koni CXT electric hoist adopts single speed variable frequency control, which can accurately match the load speed requirements.

Braking phase

When the motor is powered off, the spring pressure presses the brake ring against the brake end cover, achieving braking.

The demagnetization time (t4) ensures that the magnetic field gradually disappears during the braking process to avoid "slipping".

The braking time (ts) and deceleration ramp time work together to make the motor stop smoothly.

3、 Optimization of time parameters in practical applications

Load characteristic matching

Adjust time parameters based on load weight, inertia, and other characteristics. For example, when lifting heavy loads, it is necessary to extend the start-up delay (t2) and pre magnetization time (t3) to ensure smooth start-up.

Environmental adaptability adjustment

In high or low temperature environments, the performance of the motor and brake may vary, and the time parameters need to be adjusted accordingly. For example, in low-temperature environments, the pre magnetization time (t3) needs to be extended to ensure the establishment of the magnetic field.

Security redundancy design

When setting time parameters, safety redundancy should be considered to avoid equipment failure or safety accidents caused by improper parameter settings. For example, the braking time (ts) needs to be slightly longer than the theoretical calculation value to ensure braking reliability.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment