Cm2-Win-300 Winch - C-Max CM2 User Manual

CM2 Sidescan Sonar User Manual

16. CM2-WIN-300 Winch

16. CM2-WIN-300 WINCH
Introduction
The purpose of the optional CM2-WIN-300 portable winch is to handle 4.7mm diameter, steel-armoured tow
cable. This type of cable cannot be handled manually.
The CM2-WIN-300 portable winch was introduced in 2006, superseding the SK172/SK172E series.
Installing the Winch
The winch should be secured to a flat surface using four M8 or 5/16" screws on 346 x 318mm centres. The
winch should be located at least 1.5m directly forward of the pulley or fairlead so that the angle of the cable
remains almost perpendicular to the axis of the drum.
24V DC must be provided via cables of at least 6 sq mm copper cross-sectional area, connected to a pair of
12V automotive batteries in series to give 24V, or a single 24V truck battery. A normal generator is unlikely to
be able to supply the peak starting currents.
If the supply is fused the fuses should be slow-blow of at least 50A rating.
CM2 Winch, Fixing Centres
Overload Clutch
The cable drum is driven via an internal clutch that is intended to slip under excessive load. The slipping
torque is determined by a pair of internal disc springs. The pre-load on these springs is adjusted by the four
hex-headed, clutch tension screws on the flange nearest the motor plate. If the clutch is slipping under
normal use tighten these by rotating them all one-half turn clockwise. All four screws must be rotated an
equal amount.
As a guide, with the cable almost fully wound on to the drum, the clutch should not slip until the cable is
pulled with a force in the range 50-70kg (300m cable) or 60-80kg (200m cable).
Alternatively the clutch tension screws can be reset by unscrewing each until the head is just bearing on the
flange but with no force. When all four are at this state, each should be screwed clockwise exactly 2 full turns
(720 degrees).
Soft Start
Later units are fitted with a "soft start" circuit that reduces the initial acceleration of the winch motor and
minimizes the starting surge current. The starting current is controlled by a module that is in the electrical
path from the –ve terminal of the external power connector to the –ve terminals of the contactors (relays). If
this solid-state soft start module were to fail it can be bypassed to allow the winch to continue to operate.
Version 3.6 (2008)
33