RED ROOSTER TMH-12000/4-LF, User Manual

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USER MANUAL
▪ Red Rooster Lifting Limited ▪ Nauta House, The Meadows, Oldmeldrum, Aberdeenshire, AB51 0EZ ▪ Tel: +44 (0) 1651 872101 ▪ M01-AH14-LF REV0
SPEED & LOAD LIMITER ADJUSTMENT
7.1 SPEED ADJUSTMENT
Every TMH hoist is checked at the factory to ensure the maximum hoisting speed is in accordance with the specification.
CORD CONTROL HOIST
The speed of the hoist is proportional to the amount of downward movement in the control cord, which via the cord lever controls the amount by
which the valve is opened.
MAXIMUM LOAD ADJUSTMENT
On every TMH hoist the load limiter is factory set to operate at a load ten percent in excess of the safe working load, at an operating pressure of
6 bar. Unless a lower supply pressure is to be used, the load limiter will not require adjustment.
All models in the range incorporate an adjustable load limiter.
HOW IT WORKS
Located adjacent to the control valve, the load limiter measures the pressure drop across the motor which is proportional to the load on the
motor. Once the pressure drop is increased above that of the load limiter setting, the brake is applied and the hoist will not lift the load. In this
case the load should then be reduced or a larger capacity hoist installed. The load can still be lowered when the load limiter cuts in.
7.2 SETTING THE LOAD LIMITER
Viewing the hoist from the motor end, the load limiter adjusting screw (M6 hex) is located on the left hand side on the valve cover. It is locked in
position with an M6 nut. Back off the lock nut before commencing adjustment.
▪ Set the regulator pressure to that which will be used during operation (normally 6 bar to 90 p.s.i).
▪ Turn the adjustment screw anti-clockwise until no resistance is felt and then turn clockwise until the internal spring starts to resist.
▪ Apply the safe working load in the hoisting mode slowly and then at full speed. The hoist will stop automatically.
▪ Rotate the screw one turn in a clockwise direction and again engage the hoisting mode.
▪ Continue, one rotation at a time until the load limiter fails to stop the hoist.
▪ Turn the screw 1/4 turn clockwise and ensure the load limiter is operating at this point. (If not continue in a clockwise direction a fraction
of a turn at a time until the load limiter operates.
▪ Fasten the lock nut to secure the adjustment screw.
▪ The load limiter is now set. A significant change in the operating pressure from that selected will necessitate adjustment of the load
limiter.
▪ The maximum travel of the adjustment screw is approximately eight turns, If adjusted to this point, the load limiter will not
operate. CAUTION CAUTION
Lock nut
Adjustment screw
SLOW FAST