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MHD56213 - Edition 7
Emergency Stop and Overload System
Refer to Dwg. MHP2180 on page 12.
Air supply line is connected to air control valve. When emergency
stop or overload valve is activated, all winch movement will stop.
• If winch continues to move (payout load) after emergency
stop activates, brake(s) are not holding load and may require
adjustment or repair.
When control valve senses a preset pressure difference between
ports, a pilot signal is sent to stop flow of air, all winch movement
will stop.
Emergency Stop (optional feature)
Refer to Dwg. MHP2047 on page 4.
Emergency stop device is located on the control valve. When
activated, winch drum rotation will immediately cease. To activate
emergency stop, conduct the following:
1.
Depress (push down) red palm valve, located on top of
control valve.
Emergency Stop Operation
(Dwg. MHP2047)
• If winch overload occurs, overload device, if equipped, also
stops winch. To operate winch after an overload, reduce load
and reset overload.
• Cannot be added to old style control valve. Refer to
Dwg. MHP2036 on page 10.
Emergency Stop Reset
Refer to Dwg. MHP2048 on page 4.
1.
Rotate red stop button, in counterclockwise direction until
red stop button ‘pops’ up.
2.
Winch is ready to resume operation.
Emergency Stop Reset
(Dwg. MHP2048)
Overload Device
An overload device is available on winches with the emergency
shutoff option. Overload device operation is based on differential
pressure between air motor inlet and exhaust. The overload device
is factory preset to actuate at 150% (± 25%) of winch rated
capacity. When an overload condition is sensed, the valve poppet
closes, to cut off supply air to winch, stopping winch operation. If
an overload shutoff occurs, winch load must be reduced. Reset the
overload valve and operate winch in payout direction to lower
load. Refer to ‘Emergency Stop Reset’ section on page 4.
Overload Valve Adjustment
Refer to Dwg. MHP2216 on page 5.
5/16 in. or 8 mm open ended wrench required.
1.
Adjust overload valve by turning adjustment screw located at
bottom of control valve.
2.
Rotating adjustment screw clockwise will increase pressure
required to activate overload valve.
• This adjustment can cause overload device to NOT activate
before winch’s safety limit is exceeded. This procedure should
only be done by personnel trained in testing and servicing this
winch.
3.
Rotating adjustment screw counterclockwise will decrease
pressure required to activate overload valve.
