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© Munters AB, 2020
•
check that the protection devices (fuses, magnetothermic switches) are correctly sized, and that the phases are
connected in the correct order: check that the fan rotates in the direction of the arrow shown on the driven pulley
(see fig. 19).
fig.19
Equipotential earthing wiring safeguard
To create effective protection against the risk of electrocution, the outer protection conductor must be connected to terminal
PE inside an electrical panel.
For correct sizing of the protection conductors, see following requirements as indicated in standard IEC EN 60204-1:
•
phase conductor up to 16 mm
2
: section of the protection conductor equal to the section of the supply conductor;
•
phase conductor between 16 and 35 mm
2
: section of protection conductor equal to 16 mm
2
;
•
phase conductor over 35 mm
2
: section of protection conductor equal to at least half the section of the supply
conductor.
WARNING
When connecting all the metal masses to the earth system, check that there are no insulating
elements between the various conductive masses (metal parts). The system must not be put into operation unless
the equipotentiality of the masses and the connection to the earth system have previously been checked.
Protection against contact voltages
The choice of device to protect the electrical system must be made in such a way as to ensure the safe intervention of the
main automatic switches and any differential devices linked to them. For an appropriate choice of the type of protection for
the machine’s supply line, taking into account whether the distribution system is TT or TN, it is advisable to consult an
electrical systems designer, in order to ensure compliance with the requirements of standard IEC 64-8 or the equivalent
provisions in the country where the machine is being installed.
5.4 Tests and checks before startup
Before startup, it is extremely important to carry out a very careful check of the fan, in order to prevent malfunctions and/or
accidents.
In particular, perform the following operations:
1. Equipotential earthing wiring safeguard:
•
check the fan visually, verifying that there are no particular mechanical irregularities or foreign bodies inside the
structure;
•
check that the protective structures (fixed guards made of metal mesh) are correctly positioned and fixed;
•
check that the emergency stop function actuator operates correctly.
WARNING
Tension the belt after three days of operation: improper tension will lead to premature wear on the
transmission devices.
2. Checking the electrical system:
•
check that the supply conductors are properly fixed to the terminals of the isolating switch;
•
check the connections of the conductors in the equipotential earthing wiring safeguard;
•
check that the guards inside the electrical panel are correctly positioned and fixed;
•
check that the safety devices are receiving power and are active, and check their effectiveness.
