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OPERATION AND MAINTENANCE OF ELECTRIC ACTUATORS
Operation of the electric actuators results from the operating conditions and, as a rule, it is limited to giving impulses
to respective functional tasks. The electric actuator can be controlled electronically in remote way as well as manually on
site of their installation. Manual control is possible by means of a hand wheel of the electric actuator, it does not require
any change-over switch and can be used without any danger to the staff even in case that the electric motor is running.
The operator should take care that a prescribed maintenance is carried out, the electric actuator is protected against
dangerous effects of the environment and weather conditions which are not listed in the chapter “Working Conditions”.
Moreover, care should be taken to prevent abnormal heating-up of the surface of the solid closure of the electric actuator.
It is also necessary to monitor that the rated values are not exceeded and that abnormal vibrations of the electric actuator
do not occur.
Maintenance
The maintenance of electric actuators lies in possible replacement of defective parts. Grease filling is stable for the
electric actuator service life, i.e. 6 years. If the electric actuator is capable of operating even after 6 years the old grease
should be taken out from the power part and new grease filled in.
After 6 months at most from putting the electric actuator into operation and then at least once a year, the connecting
screws between the piping fitting and the electric actuator should be retightened. The screws are tightened
in a crosswise manner.
Cleaning - general inspection
The electric actuators ex should be kept clean and care should be taken to prevent their clogging by impurities and
dust. Cleaning should be carried out regularly and as often as required by operating conditions. Surface temperature
of the actuator 80 °C (T6) should be determined without a dust layer. From time to time, it should be verified whether all
connecting as well as earthing clamps are duly tightened to prevent their heating up during operation. General inspection
of the electric actuator is recommended to be carried out once a year unless otherwise stated in revision regulations
of electric devices.
Checking the parts of non-explosive closure
The parts of the electric actuator forming the solid closure are inspected for possible ruptures or other damages
(attacked by corrosion, abrades etc.). With the electric actuator disconnected, sealing rings of cable outlets should be
inspected. Material of the sealing rings undergoes ageing and its hardness increases. Therefore, after 3 years they should
be replaced during the reassembly. Defective parts of the closure must not be used again during assembly of the electric
actuator.
In all relevant repairs of the non-explosive closure which effect its safety it is recommended to have the electric actuator
ex repaired at the manufacturer who can, on the basis of approved documentation and prescribed tests, put the closure
into a state corresponding to ČSN EN 60079-1.
Содержание Modact MOKP 100 Ex Series
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