Checking The Pilot Signal Cable Function; Parameters For Use With A Variable Frequency Drive; Maintenance; General Inspection - Nederman RBU Bedienungsanleitung

• Check that the vacuum level on the vacuum meter,
Figure 3 item 15, corresponds the specified levels in
Section 3.1 Technical data. See
level for more information about checking the vacu-
um level.
7.2.5 Checking the pilot signal cable func-
tion
For units with pilot signal cable also ensure the fol-
lowing at initial start-up:
• The unit only starts directly when one of the follow-
ing occurs:
• A valve is opened at a worksite, causing the mi-
croswitch to close.
• The test start button is pressed on the start- and
control unit (if available).
• After a delay, the unit goes into idling mode. The
unit remains in idling mode for a specified time be-
fore stopping.
7.3 Parameters for use with a variable
frequency drive
Models intended for use with variable frequency
drives need to maintain a minimum frequency of 20
Hz in order to ensure sufficient lubrication of the
pump. Running the unit at frequencies lower than this
risks damaging the pump. The highest frequency the
unit is intended for use with is 60 Hz. At frequencies
above this, the motor is at risk of overloading.
The U/f ratio curve used by the variable frequency
drive shall be a linear function Stopping of the motor
shall be performed with an unpowered coast to stop.
It is strongly recommended that in the case where
there are no active users the start-up valve is opened
and for models intended for use with a variable fre-
quency drive the frequency is set to the lowest allow-
able. This ensures minimal power consumption for
periods where a strong vacuum is not required.
8 Maintenance
Read Chapter 2 Safety before carrying out mainten-
ance.
It is recommended to install an hour service meter in
the start- and control unit.
The intervals in this chapter are based on the
unit being professionally maintained.
Inspections in the unit are recommended to be made
with only the enclosure roof removed.
WARNING! Risk of hearing impairment
Use hearing protection. The sound level is very
high when the unit is run with the enclosure
roof removed.
RBU
Section 8.11 Vacuum
8.1 General inspection
Perform the following general inspection every 500
hours of operation:
• Inspect the incoming connections. Ensure that all
• Check for signs of corrosion or other damage.
• Check that the ventilation inlet and outlet of the
• Check that the ventilation to the room is clear (if
• Check for dust or collected material inside the unit.
8.2 Belt transmission
Perform the following belt transmission inspection
every 500 hours of operation:
1
2
3
4 Check the tension of the belt transmission and ad-
5
6
WARNING! Risk of electric shock
Work with electric equipment must be carried
out by a qualified electrician.
WARNING! Risk of personal injuries
Use proper protective equipment when risking
exposure to the dust.
WARNING! Risk of electric shock
Always disconnect the supply voltage before
any servicing, whether mechanical or electrical.
Always lock any maintenance switch in the off
position.
WARNING! Risk of personal injury
Ensure that the vacuum meter, see
item 15, shows that no vacuum is present in
the system during service.
WARNING! Risk of burn injury
Make sure the unit is cool before undertaking
an inspection to avoid burn. The unit and its
parts can get very hot.
cables and hoses are tightly fitted.
unit are clear.
placed indoors).
Dust or collected material may indicate a filter mal-
function.
Remove the belt guard, see
Remove the motor side panel for easy access to
the screws that anchor the motor.
Replace worn or damaged belts and pulleys.
The lengths of the belts in the set must be
matched according to tolerances given in
ISO 4184.
just if required. Use Table 8.1
as shown in Figure 8.
Put back the motor side panel.
Put back the belt guard.
Figure 3
Figure 1 item 7.
as a guide for force F
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EN