Main components
The following components are shown in
figures 1-5.
1) 5-pole electrical connection
2) Compressed air connection
3) Operating switch On/Off
4) Discharge air from high pressure fan
5) Cooling air to motor
6) Ventilation opening
7) Coupling sleeves for vacuum
8) Vacuum hose (optional)
9) Cover lock for non-used sleeve
10) Collection box for coupling sleeves
11) FlexFilter dust collector (cyclone or filter)
12) Start equipment ”High Vacuum Starter”
13) Water and dirt collector for compressed air
14) Electric motor
15) Cooling air hose
16) 2-stage high pressure fan
17) Thermal switch, RTS, for fan bearings
18) Thermal switch, TS, for fan housing
19) Temperature control valve, type TAV 50 MV, 24 V
AC
20) Start-up valve, type SUV 200, 24 V AC
21) Flow restrictor (in certain cases)
22) Outlet silencer
23) Transmission and belt guard
Positioning and connection
C-PAK must be placed on a firm surface that can
withstand the weight of the unit and the weak vibra-
tions that arise during operation. The positioning can
be affected by the dust collector that is selected. If
the dust collector is a cyclone (no filter), it is impor-
tant that personnel are not exposed to the fine partic-
les that escape from the plant. Gases that are suck-
ed out together with, for example, welding smoke are
not collected even if a filter has been installed.
Therefore, C-PAK must be placed in an open space
so that gases do not congregate.
Never place C-PAK so that the connection side (fig.
1) is close to a wall. This is to ensure the best pos-
sible cooling and ventilation conditions.
The electric power cable must be suitable for the
mains fuses installed. Recommended fuses, in rela-
tion to supply voltage and motor power, are found in
the starter manual which is enclosed.
C-PAK must always be connected to compres-
sed air. Otherwise, the overheating protection for
the fan and the filter cleaning (for collectors with a
filter) will not work. Units manufactured in 1999 or
later have a compressed air switch, CAS, which
ensures that the unit can not be operated without
compressed air. Older units can be equipped with a
CAS.
At least one suction hose must always be connec-
ted. Non-used sleeves must be shut with their cover
lock. Hoses that are not used must be disconnected
so that the full capacity is available where it is best
needed. Unnecessary airflow increases the unit’s
energy consumption.
Initial start-up
Check the motor’s direction of rotation after each
new electrical connection. The wrong direction
results in bad suction and risk for fan overheating.
If the compressed air is missing, do not start the
motor. A red lamp lights up on the starting equip-
ment when you attempt to start-up. Note that at
least one suction hose must be connected.
Function
The following section is found in the manual for the
VAC 20. This section is also relevant for C-PAK, alt-
hough CAS, which is an option in VAC 20, is moun-
ted as standard in C-PAK.
If C-PAK is equipped with a dust collector with filter,
a manual for the dust collector is also supplied. The
manual for High Vacuum Starter is always supplied.
VAC 20 is a series of vacuum units that operate at 20
kPa (80" W.G.) vacuum for an air flow up to the spe-
cified level. Units can be delivered for different capaci-
ties and for several voltages at frequencies of 50 or
60 Hz. The motor is a 3-phase asynchronous motor.
Motor power is designed to match the capacity of
the unit.
The vacuum source is a belt-driven 2-stage high-
pressure fan. The fan has fan characteristic, which
means that the power consumption increases with
increasing airflow. During Y/D - starting of such a
fan, it is necessary to minimise the power require-
ment by restricting the airflow while the motor is
operating in Y-mode. Accordingly, all VAC 20 units
have a start-up valve SUV 200 at the fan inlet. The
valve is closed, apart from a small leakage flow,
when the unit is at stand still or during start up in Y-
mode. Not until the motor switches over to full
power in D-mode will the valve open. The valve is
controlled from the unit's Y/D - starter. The "High
Vacuum Starter" from Nederman High Vacuum
Systems has this feature as standard.
Most VAC 20 units are fitted with a flow restrictor,
FR 160, mounted close to the fan outlet. The flow
restrictor remains fully open until the flow reaches
the volume corresponding to the unit's rated capaci-
ty. If the flow shows signs of increasing, the valve
gradually closes so that the flow does not exceed
the rated value. This protects the motor from overlo-
ading.
Should the airflow through a high-pressure fan sink
too low the fan will run hot and begin ”pumping”.
2 (3) GB
