Emcee 1004156, Руководство пользователя

Страница: 63 / 66

General Manual Electric Winches with UMPH rope-English Rev.1.1 – 10-12-2014
ANNEX IV: GUIDELINES TO COMPLY WITH THE MACHINERY DIRECTIVE 2006/42/EC
Rated capacity limiters:
Winches with a rated capacity of 1000 kg or more shall be fitted with a rated capacity limiter in accordance with
EN 14492-1 section 5.2.2.1.
The rated capacity limiter shall be designed to prevent overloading of the winch. It shall also limit the forces
transmitted to the supporting structure, which are to be provided by the manufacturer. Overloading means
exceeding the designed operating forces.
For electric winches normally an indirect acting rated capacity limiter is used. The triggering factor of an indirect
acting rated capacity limiter should be equal or less than 125% off the rated capacity of the winch in the first
layer of the drum. Most common is to use a device that limits the running current of the electric motor. If such a
devise is used care must be taken to allow the motor to overcome the starting current before the rated capacity
limiter is activated. Alternative methods may for example be a load measurement with a load pin on a diverter
sheave, a dynamometer or a torque limiter programmed in a frequency inverter.
When the rated capacity limiter is activated the winch should stop lifting and should only be able to lower.
Normally the controls are designed such that the rated capacity limiter is reset when the controls for lowering
are applied.
Controls
Devices for starting and stopping manually controlled winches shall be fitted with hold-to-run control elements
so that the drive energy supply is interrupted when the actuating elements are released.
Controls for electric winches shall be in accordance with EN 60204-32. For electric powered winches guide lines
are given in EN 14492-1 section 5.12.
The electrical devices on a winch shall contain a device for isolation of the electrical equipment from the mains
power supply so that work may be performed without the risk of a electric shock or burning. Besides an
isolation switch on the control panel this function may also be fulfilled by a crane-supply switch, a crane switch,
or as described in EN 60204-32, 5.3.2, letter d), a plug/socket combination.
Lifting and lowering limiters
Winches shall be fitted with lifting and lowering limiters in accordance with EN 12077-2 section 5.6.1.
The following prescriptions shall apply in addition to those stated in EN 12077-2.
Electrical limiters shall have a positive opening system.
After operation of a limiter, it shall be ensured that the limiter does not return to its original position until
the corresponding restricted area has been left by the actuating parts.
The lowering limiter shall ensure that the minimum engagement of the lifting medium is maintained at all
times during operation. The lowering limiter shall also stop the motion to prevent unwanted coiling in the
reverse direction.
For normal operation a second limiter , as defined in EN 12077-2 section 5.6.1.1 is not necessary. A
risk assessment based on the particular application may result in the need of a second limiter for certain
motions. This second limiter shall not be approached during normal operation, whereas the first limiter
can be approached during normal operation.
For most winches a spindle limit switch on the drum shaft with 2 contacts is used as an upper and lower limit
switch. In case the limit switches are also used as position switches local switches actuated by the lifted
structure should be used.
Protective guards
Drum and other running parts of a winch located in an easily accessible position shall be protected by opportune
guards. For winches in an easily accessible position a drum guard is required.