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RBU
EN
3 Description
The RBU (Roots Blower Unit) is a series of vacuum
units fitted with a 3-lobe root pump vacuum source.
See
formation. The motor is a 3-phase asynchronous mo-
tor. See the RBU unit machine tag for details regard-
ing voltage, current, motor power, and frequency.
The root pump’s power consumption increases with
increasing vacuum and decreasing airflow (pump
characteristics).
For Y/D started models it is necessary to minimise the
power requirement during Y/D-starting. This is done
by opening a solenoid valve for free admittance of air
to the pump when the motor runs in Y-mode.
All RBU units are fitted with a combined start-up and
vacuum limiting valve. This valve is controlled by low
friction compressed air cylinder, a solenoid valve
and two regulators. The valve opens if the vacuum
reaches the working vacuum level or the safety vacu-
um level. When the valve opens incoming air lowers
the vacuum. The opening of the valve will depend on
(1) the vacuum in pump and (2) the force of the low
friction compressed air cylinder pulling the valve in
the opposite direction. The force in the compressed
air cylinder rises when air pressure fed to the com-
pressed air cylinders raises. In this way, the regulat-
ors adjust the vacuum by affecting the valve disc po-
sition which in turn changes the air pressure to the
compressed air cylinder.
The working vacuum level is adjusted using the regu-
lator closest to the cylinder, see
item 15. The
level is set before delivery and no further adjustment
is normally required. See
regarding regulator adjustment.
CAUTION! Risk of equipment damage
The safety valve regulator must never be ad-
justed,
item 16. Incorrect setting of
the safety valve regulator damages the pump
and the warranty will be rendered invalid.
At the universal valve, entrance is a rubber disc back-
flush valve. The valve is used when two or more RBU
units are hooked up in parallel and prevent units not
yet started from running backwards.
A rubber disc overpressure valve is placed on the uni-
versal valve side, see
item 18. The overpres-
sure valve opens and lets air out if the pump runs in
the wrong direction during the initial start-up.
After the universal valve, the air passes through the
inlet silencer to the roots pump. Underneath the pump
is a rigid discharge silencer. An additional spiro bend
silencer leads the air out from the unit.
On Y/D started models a thermal fuse is placed in the
lower flange of the pump, see
item 10a. This
fuse trips at ≈ 140 °C (≈ 284 °F) with an indication to
the start- and control unit which stops the unit. See
for more information.
On models intended for use with a variable frequency
drive, the pump temperature is monitored with a
PT1000 temperature sensor. The pump must be
stopped if the pump temperature reaches 140.
Models intended for use with a variable frequency
drive are also fitted with PT1000 temperature
sensors for monitoring the motor's surface temper-
ature as well as the temperature of the cooling air in-
take.
3.1 Main components
shows the main components of the RBU unit.
These are as follows:
1
Inlet silencer.
2
Outlet spiro silencer.
3
Noise-absorbing enclosure.
4
Spiro silencer with a 90° bend.
5
Motor.
6
Transmission.
7
Belt guard.
8
Discharge silencer.
9
Base.
10 a) Thermal fuse. b) PT1000 temperature sensor
(on models intended for use with a variable fre-
quency drive).
11 3-lobe roots-pump.
12 Inlet silencer with safety grating.
13 Universal valve. This is a combined vacuum limit-
ing valve, backflush valve, and overpressure valve.
14 Vacuum limiting valve disc.
15 Maximum work vacuum regulator.
16 Safety vacuum regulator. The regulator must not
be adjusted.
17 Inlet safety grating.
18 Overpressure valve.
3.2 Connections
The motor is connected electrically with the enclosure
roof removed. See the start- and control unit’s manu-
al for electrical connections. Connections may vary de-
pending on the options. Connecting material such as
cables is not included with the unit. Different dust col-
lectors are available; see the manual of the dust col-
lector for details.
Start- and control units from Nederman have termin-
als for easy connection of all control cables. If other
equipment is used, this equipment must be similarly
equipped and connected for the guarantee of the RBU
unit to be valid. Most failures are result from faults
in the electrical equipment or connections. The mo-
tor overload relay must be of the ‘heavy start type’ as
some units are heavy to start. Otherwise, the motor
16
Содержание RBU 1300
Страница 2: ...RBU Trace back information Workspace Main version a67 Checked in 2022 10 17 Skribenta version 5 5 022...
Страница 8: ...RBU Figures 5 6 11 12 13 8 4 9 3 7 10a 18 14 15 16 17 2 1 10b 1 8...
Страница 11: ...RBU 6 7 10 mm 0 39 8 11...
Страница 12: ...RBU Nm h kPa 9 Nm h kPa A A 10 12...
Страница 210: ...RBU RU 7 7 220 7 8 220 7 9 220 7 10 220 7 11 220 7 11 1 220 7 12 221 8 221 8 1 221 9 221 10 B 222 11 B 224 210...
Страница 211: ...RBU 1 Nederman Nederman Group Nederman Nederman EC Nederman Nederman Nederman 2 2 1 2 2 RU 211...
Страница 214: ...RBU RU 500 3 3 5 5 214...
Страница 218: ...RBU RU 6 2 6 2 1 1 2 1 2 3 a b 4 4 6 2 2 Y D Y D D Y Y D D 6 2 3 7 10 6 2 4 3 15 3 6 7 11 6 2 5 6 3 20 60 U f 7 2 218...
Страница 222: ...RBU RU 10 B 4 4 4 2 3 6 4 1 3 2 5 1 4 2 5 2 3 2 3 2 5 222...
Страница 223: ...RBU 5 3 5 3 ISO 8573 1 5 5 3 5 3 5 3 6 2 6 2 6 2 6 2 Y 6 2 D 6 2 6 2 RU 223...
Страница 224: ...RBU RU 11 B 7 1 7 1 5 1 7 2 7 2 7 2 7 3 7 4 7 5 7 12 Nederman 7 9 7 9 224...
Страница 225: ...RBU 7 8 7 10 7 10 7 11 7 7 7 6 RU 225...
Страница 242: ...RBU ZH 7 7 250 7 8 250 7 9 250 7 10 250 7 11 250 7 11 1 250 7 12 250 8 250 8 1 250 9 250 10 A 251 11 B 253 242...
Страница 243: ...RBU 1 Nederman Nederman Nederman Nederman EC Nederman Nederman Nederman 2 2 1 2 2 ZH 243...
Страница 251: ...RBU 10 A 4 4 4 2 3 6 4 1 3 2 5 1 4 2 5 2 3 2 3 2 5 5 3 5 3 ISO 8573 1 5 5 3 5 3 ZH 251...
Страница 252: ...RBU ZH 5 3 6 2 6 2 6 2 6 2 Y 6 2 D 6 2 VFD 6 2 252...
Страница 253: ...RBU 11 B 7 1 7 1 5 1 7 2 7 2 7 2 7 3 7 4 7 5 7 12 Nederman 7 9 7 9 7 8 7 10 7 10 7 11 7 7 ZH 253...
Страница 254: ...RBU ZH 7 6 254...
Страница 255: ...www nederman com...