Inverters-FREQROL-A800 Plus Series　-FREQROL-A800 Plus for CRANES- Suited for various cranes to achieve fast, robust, and smooth operations

Reduction in tact time 

Anti-sway control

By using Mitsubishi Electric's original anti-sway control technology, the swinging of an object moved by a crane is suppressed at the time of stopping, even without operator's input adjustment.
This control cuts down the tact time and facilitates efficient operation.

Load torque high-speed frequency control (mode 2)

When there is a light-load (when light loads are moved up or down by a crane), the speed will automatically be increased. This reduces the tact time and facilitates efficient operation.
The possible operation speed is set automatically according to the load. After starting the inverter, the inverter runs at high speed with a light load.

Built-in brake transistor

22K inverters or lower in the 200 V class and 55K inverters or lower in the 400 V class have a built-in brake transistor.
Connecting a brake resistor^*1 can shorten the deceleration time; no brake unit or power regeneration converter is required.

• *1The brake resistor must have a sufficient capacity to consume the regenerative power.

Shortest-time torque startup function

The time from the start command to when the brake opens is shortened. This will contributes to reduction in tact time.

• Shortest-time torque startup function :
  The optimum distribution of the excitation current and torque current enables rapid startup of the torque.
• Magnetic flux command during pre-excitation :
  Decreasing the pre-excitation current during a motor stop reduces power consumption during standby, and enables rapid startup of the torque.

Load slippage prevention 

Brake sequence function

The highly scalable brake sequence function enables the output of a brake opening signal for the optimum brake operation calculated from the load torque or the speed.
The function enables setting of the brake opening level individually for forward rotation and reverse rotation.

Low-speed range speed control P gain

When an inverter is connected to a lift, the inverter has a load immediately after the lift brake is released. Adjusting the speed control P gain in the low-speed range improves the response at low speed, and shortens the time from startup to brake opening.

Falling detection

Slippage during the start of a lift can be checked.
When the commanded direction differs from the actual motor rotation direction, the falling detection signal is output.

Dedicated monitoring functions 

Overload detection function

By outputting an overload detection signal when too much load (overload) is applied to a crane, this information can be transmitted to the superordinate controller.
During constant speed operation, when the motor torque is equal to or higher than the torque setting for the time setting or longer, the overload detection signal is turned ON.

Start count monitor

The inverter starting times can be counted.
Confirming the starting times can be used to determinate the timing of the maintenance, or can be used as a reference for system inspection or parts replacement.

Start count monitor

Wide range of applications

Compliance with ship classification standards

Using the recommended noise filter in combination with the inverter supports compliance with various countries ship classifications, such as NK, LR, DNV GL, ABS, BV, CCS, and KR.
The FR-A800-CRN can be used for electric deck cranes on ship.