widmer Rockair K-494 Manual De Uso Y Mantenimiento página 19

Three-phase compressors (L1+L2+L3+PE) must be installed by
a specialised technician. Three-phase compressors are supplied
without a plug. Connect a plug, with screw-on grommet and securing
collar (fig.13), to the cable, consulting the table below.
HP kW Power supply volt/ph
2 – 3 – 4 1.5 – 2.2 – 3
5.5 – 7.5 – 10 4 – 5.5 – 7.5
NOTE: The equipment must be connected to a maximum impedance
of 0.37 Ω.
NOTE: Compressors installed on the 500 lt tank, with capacity
of HP7.5/5.5 kW and HP10/7.5 kW can be supplied a star/triangle
starting control unit, whereas the TANDEM (n. 2 pumping elements
on the same tank) are supplied with a timed control unit for staggered
starting of the two pumping elements.
Installation instructions:
– Secure the control unit box on a wall or on a fixed support, and
provide it with a power cable with plug, of a diameter in proportion to
its length.
– Any damage caused by incorrect connections of the power line
to the mains, automatically excludes warranty of electrical parts.
To avoid connection errors, we advise you to contact a specialised
technician.
IMPORTANT:
Never use the ground socket instead of the neutral wire. The ground
connection must be made to meet safety standards (EN 60204). The
plug of the power cable must not be used as a switch, but must be
fitted in a power socket controlled by a suitable differential switch
(thermal-breaker).
STARTING
Check that the mains power matches that indicated on the electrical
data-plate (fig.14) the permissible tolerance range is +/-5%. When
first starting compressors operating on 3-phase voltage, check the
rotation direction of the cooling fan by comparing it with the direction
of the arrow on the belt guard or on the protective housing. In the
SILENT compressor, check if the air flows is in the direction illustrated
in fig.21A. Turn or press into position "0" (according to the type of
pressure switch fitted on the appliance) the knob located on the upper
section (fig. 15). Fit the plug in the power socket (fig. 12 - 13) and start
the compressor, turning the pressure switch knob into position "I".
The compressor is fully automatic, and is controlled by the pressure
switch which stops it when tank pressure reaches maximum value
and restarts it when it falls to minimum value. The pressure difference
between maximum and minimum values is usually about 2 bar (29
psi). E.g.: the compressor stops when it reaches 8 bar (116 psi –
maximum operating pressure) and restarts automatically when the
pressure inside the tank drops to 6 bar (87 psi). After connecting the
compressor to the power line, load it to maximum pressure and check
exactly how the machine is operating.
When the temperature is <10 ° C it is recommended to make the
first start with the tank unloaded (0 bar); it is recommended to
depressurize the tank again, in case the compressor has stopped at
low temperature within 30 minutes from the first start up.
COMPRESSORS WITH λD STARTING
CONTROL UNIT (fig. 16)
Fit the plug in the power socket (fig. 13) and turn the pressure switch
to position "I" (ON) (fig. 17). Turn the master power switch "A" on the
control unit to position "I" – power On is signalled by white indicator-
light "E" going on. Turn switch "B" to position 1 to start the compressor.
If the solenoid-valve indicator-light "D" and the motor indicator-light
"C" go on in that order, this means the machine is operating perfectly
(fig. 18).
Plug model
220/380/3
230/400/3 16A 3 pole + ground
220/380/3
230/400/3 32A 3 pole + ground
TANDEM COMPRESSORS WITH TIMED
CONTROL UNIT (fig. 17)
Fit the plug in the power socket (fig. 13) and turn the pressure switch
to position "I" (ON). Turn the master power switch "A" on the control
unit to position 1 – power On is signalled by white indicator-light "E"
going on; turn switch "B" to start the compressor.
Pos. 1 pumping element n. 1 only is operating; Pos. 2 pumping
element n. 2 only is operating; Pos. 3 both pumping elements are
operating simultaneously, at staggered starting times.
The compressor is fully automatic, and is controlled by the pressure
switch which stops it when tank pressure reaches maximum value
and restarts it when it falls to minimum value.
NOTE: The head/cylinder/delivery tube unit can reach high
temperatures. Take care when working near these parts, and do not
touch them to avoid possible burns (fig. 18 - 19).
The electro-compressors must be connected to a power socket
protected by a suitable differential switch (thermal-breaker). The
motor of GM compressors is equipped with an automatic thermal
breaker located inside the winding – this stops the compressor when
motor temperature reaches excessively high values. If the breaker is
tripped, the compressors restarts automatically after 10 to 15 minutes.
The motors of compressor models VX are supplied with a manually
resetting automatic amperometric thermal-breaker, located outside
the terminal board cover. When the breaker is tripped, wait for a few
minutes and then reset the breaker manually (fig. 20). The motors
of the AB series compressors are supplied with a manually resetting
amperometric thermal-breaker, located on the terminal board cover.
When the breaker is tripped, wait for a few minutes and then reset the
breaker manually (fig. 20).
The safety device is automatic in three-phase and Silent compressors.
When the thermal-breaker is tripped, the pressure switch is released
to "0" (OFF) position. Wait for a few minutes and return the pressure
switch to "I" (ON) position. For compressors supplied with a control
unit, the thermal-breaker is installed inside the control unit.
When the thermal-breaker is tripped, observe the following procedure
(fig. 22):
- Turn the switches on the control unit cover to position "0",
open the cover and press push-button 1 of the thermal-breaker.
Close the cover of the control unit and restart the compressor,
observing the operations described in the paragraph "Starting
compressors with control unit".
The same instructions apply to compressors powered at 60 Hz.
ADJUSTING OPERATING PRESSURE (fig. 23)
You do not have to use the maximum operating pressure at all
times. On the contrary, the pneumatic tool being used often requires
less pressure. On compressors supplied with a pressure reducer,
operating pressure must be correctly adjusted. Release the pressure
reducer knob by pulling it up, adjust pressure to the required value by
turning the knob clockwise to increase pressure and anti-clockwise to
reduce it. When you have obtained optimum pressure, lock the knob
by pressing it downward (fig. 23). For pressure reducers equipped
without a pressure gauge, the set pressure can be seen on the
graduated scale located on the reducer body. On pressure reducers
equipped with a pressure gauge, pressure can be seen on the gauge
itself. WARNING: Some pressure regulators do not have "push to
lock", therefore simply turn the knob to adjust the pressure.
MAINTENANCE
Before attempting any maintenance jobs on the compressor, make
sure of the following:
– Master power switch in position "0".
– Pressure switch and the control unit switches all off, in position "0".
– No pressure in the air tank.
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IMPORTANT
EN