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2) Constant Tension mode:
In tension mode the winch is operating on a torque input signal or a load-cell signal and the winch
drum speed cannot be adjusted, because when tension mode is selected, it is the tension in the
umbilical that has the determining factor. The winch will heave or slack to adjust to the applied load
setting shown in the display.
For more details see section 5.2.2
Brake resistor
The brake resistor is basically an industry quality fan heater to get rid of the power generated by the
umbilical winch during umbilical pay-out or de-acceleration of the winch.
Warning:
The voltage is 700VDC 20 amp output from the winch to the brake resistor.
Level Wind
To help spooling the umbilical onto the drum the winch is equipped with an electronic controlled level
wind. The level wind is driven by an electric asynchronous motor and a frequency converter. An
absolute encoder is placed on the winch drum and one on the level wind. The PLC calculates the
necessary movement of the level wind with respect to the umbilical diameter and the rotation of the
drum. Input regarding the umbilical diameter is done on the operator’s panel. We recommend that the
diameter input is set to app. 1,02-1,04 x actual diameter of cable. If a correction is made by punching
in a new value for the diameter the PLC will calculate trough all the layers and finally correct the
position of the trolley.
Never cut back umbilical or adjust on level wind manually without following the
instructions in the manual. This can result in a mismatch between umbilical drum
and level wind.
Title:
Author:
Winch Offshore Manual MASH 2000
JBK
Revision:
Date:
B
24-01-2012
Page:
8 of 78