The enclosed compressed air filter must be installed
EN
to ensure the reliable and safe operation of the unit.
The compressed air valve vents the remaining pres-
sure of the unit.
Take necessary measures to avoid water or hu-
midity in the compressed air when the unit is
installed in cold environments.
If antifreeze additives are used, use them con-
tinuously. Once added, the removal of anti-
freeze additive can cause the pneumatic com-
ponents to malfunction.
6.3.2 Installation
Connect a compressed air supply to the inlet, see
ure 3
item 7, and Section 4.1 Connections.
Connect the vacuum meter,
tion 4.1 Connections.
6.4 EMC
Units intended for use with variable frequency drives
are fitted with EMC compatible cable glands. EMC com-
pliant, screened cables must be used.
6.5 PTC
The motor has added thermal protection in the form
of three PTC devices connected in series and embed-
ded in the windings. Connections to the motor thermal
protection are available in the motor terminal box. It is
strongly recommended to use the motor PTC to stop
the unit, should an over-temperature be detected and
is mandatory for units intended for use with a variable
frequency drive.
7 Using RBU
7.1 Before start-up
The vacuum unit and any auxiliary options are tested
before delivery and all functions are checked. A test
report accompanies each unit.
Ensure the following before the initial start-up:
• The maintenance switch is installed (if used).
• The installation room has ventilation openings (if
used indoors), see
• Dust collector, duct and valves at the worksites are
connected.
• Exhaust air is ducted away from the installation (if
used indoors).
• Make sure the exhaust duct is protected from rain
and snow.
• Make sure the exhaust duct is fitted with a grid so
no foreign objects can get into the duct.
• The compressed air supply is permanently fitted.
• All electrical connections have been correctly made
as in Figure 6-Figure 8.
18
Figure 3
item 15 and
Section 6.1 Indoor installation
RBU
• Nederman start- and control units have the termin-
als connected, and in some cases jumped connec-
tions. Verify the connections using the connecting
diagrams.
• The pilot signal cable from all valves is linked to the
start- and control unit on units with automatic start/
stop.
• All valves at worksites are closed.
• Ensure that the belt guard is properly in place.
7.2 Initial start-up
7.2.1 Checking the direction of rotation
At initial start-up, check the direction of rotation by
Fig-
doing the following:
1
Start the unit.
Sec-
2
Compare the direction of the motor rotation with
the arrow on the motor.
• If the direction of the motor and the arrow are
the same, allow the starting procedure to con-
tinue.
• If the direction of the motor is different from the
direction of the arrow, change the direction of
the motor by doing the following:
1
Stop the unit.
2
Disconnect power.
3
a) Open the start- and control unit.
b) For models intended for use with a vari-
able frequency drive, switch two of the mo-
tor supply conductors and skip step 4.
4 Switch two of the incoming phase conduct-
ors.
7.2.2 Checking the Y/D time setting
The Y/D time setting is factory preset and does
not normally need to be adjusted.
Switching to D mode before the motor has reached
full speed can damage the start- and control unit. This
is particularly important when an automatic start and
stop is installed. Too long in Y mode results in an un-
necessary delay before the unit delivers full vacuum.
At initial start-up check the Y/D time setting by doing
the following:
• Make sure the motor sound is constant and high
pitched, indicating full motor power, before the mo-
tor switches to D mode.
7.2.3 Checking the start-up and vacuum lim-
iting valve
Perform the check of the start-up and vacuum limiting
valve as described in
um limiting
valve.
7.2.4 Checking the vacuum level
At initial start-up ensure the vacuum level is at the
correct level by doing the following:
Section 8.10 Start-up and vacu-