The absolute rotary encoder is mounted on the gear limit switch and determines the exact position of the cable drum, and then reports this to the PLC.

The ABUS gear limit switch "GGS" with absolute rotary encoder "AWG" is fully compatible with the "GPK" hoist limit switches with "Kübler" absolute rotary encoders. If necessary, a "GPK" hoist limit switch can however be installed with a "Kübler" absolute rotary encoder.

Disassemble the faulty gear limit switch.

Install new gear limit switch.

See product manual "ABUS gear limit switch with absolute rotary encoder", section "Installing and connecting gear limit switch“.

Reset switching points for the bottom hoist limiter, the top hoist limiter and the backup limiter. ‎

See Setting switching points for backup limiter and top hoist limiter, page  .

See Setting switching point for the bottom hoist limiter.

For further details about the terminating resistor: See Setting the terminating resistor in the CAN bus network.

The absolute rotary encoder is controlled by the central PLC via a device address. The device address is automatically set.

The device address is a digital unique address of each CAN bus device in the CAN bus network, via which the PLC and the respective CAN bus device exchange data. Each CAN bus device must have its own unique device address. If two CAN bus devices inadvertently have the same device address there will be a conflict and a fault is displayed.

The bit rate is the speed with which the data is exchanged.

Setting the device address automatically:

If the base address is set on the absolute rotary encoder, the correct device address is automatically set by the PLC. See also Overview: Device addresses, page  .

The PLC doesn't find a component at the expected device address, instead it finds a CAN bus device with a base address.

●   The PLC converts the base address of the CAN bus device to the expected device address.

Setting device address manually:

The device address of the absolute rotary encoder can be manually set in KranOS.

For this work step, access from a laptop or tablet computer to KranOS is necessary. The user "Abnahme" (commissioning) (user level ‚[2]) or "Service" (user level [1]) must be logged in.

Log in to KranOS with user "Service" (user level ‚[1]) or "Abnahme" (commissioning) (user level [2]). See Connecting laptop or tablet computer with ABUControl, page  .

Select the desired hoist (e.g. Hoist 1) in the main menu.

●   The window for the requested hoist appears.

Click on the "Absolute rotary encoder" menu item in the "Settings" menu (gear wheel on yellow background).

●   The "Absolute rotary encoder" window appears.

If necessary: Reset a message from the absolute rotary encoder with the "Reset error" button.

●   Input the device address from the absolute rotary encoder that is to be changed in the "Actual value" input field.

The absolute rotary encoders have the base address 70 and device addresses from 71 to 76.

If necessary, the device address 63 can be input with the "Load device address 63" button. This can be necessary for older absolute rotary encoders

Enter the desired new device address in the "Target value" input field.

─     Only device addresses from address range 70 can be assigned for the absolute rotary encoder.

Click on the "Set device address" button.

●   The set device address is saved.

The absolute rotary encoder has to be referenced after it is replaced. This referencing is not part of setting the switching points for the gear limit switch, nor is it part of calibrating the load measuring system, but is instead important for internal calculations (e.g. sway control and discard prognosis). If the absolute rotary encoder is not correctly referenced, malfunctions of the sway control or incorrect calculations in the discard prognosis could occur.

The three switching points of the gear limit switch should already be correctly set before the absolute rotary encoder is referenced.

Measuring reference position:

Move the load hook to a hook position in which the reference position can be easily measured (e.g. about 1.5 m under the highest hook position).

Measure the distance from the centre of the cable drum to the centre of the deflection roller of the bottom block.

Setting the reference point:

Log in to KranOS with user "Service" (user level ‚[1]) or "Abnahme" (commissioning) (user level [2]). See Connecting laptop or tablet computer with ABUControl, page  .

Select the desired hoist (e.g. Hoist 1) in the main menu.

●   The window for the requested hoist appears.

Click on the "Absolute rotary encoder" menu item in the "Settings" menu (gear wheel on yellow background).

●   The "Absolute rotary encoder" window appears.

●   Enter the value you measured in the "Reference position" input field.

Click on the button for the desired drive (e.g. "Drive 1 referencing").

●   A confirmation prompt appears.

Click on the "Perform referencing" button.

●   Save the input value.