Speck pumpen VZ 11 B Series, Operating Instructions Manual

Page: 19 / 48

OPERATING INSTRUCTIONS
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pump, and the delivery side to the seperator
tank. Lipuid bags should be avoided.
5.3
Pipes
Suction and discharge connections as well as
the connection for the operating liquid are
sealed, when the pumps is supplied, in order
to avoid the penetration of any foreign bodies.
The seals are not to be removed before the
pipes are fitted.
The internal diametre of the suction and dis-
charge pipe as well as the pipes for the operat-
ing liquid should not be smaller than the corre-
sponding pump connections and as short as
possible. For longer pipes wider internal dia-
metres should be chosen.
The pipes should be fitted to the pump without
strain. In case of big temperature differences,
a compensator in the pipe should be provided
additionally for the suction and discharge side.
Before starting the pump the sealings of the
pipes have to be checked carefully.
5.3.1 Suction pipes
In the suction pipe a non return valve should
be mounted in order to avoid the filling of the
vacuum pipe with the operating liquid resp. in
order to avoid a pressure drop in the vacuum
system.
CAUTION
If a shut-off device (sliding valve or similar) is
fitted in the suction pipe and if the pump
should be commissioned, when this shut-off
device is closed, cavitation will occur. This will
destroy parts of the pump during a longer
working period.
5.3.2 Discharge Pipes
If in the discharge pipe or in the discharge pipe
of the liquid separator a shut-off device is
installed, it has to be taken care that the pump
will not be operated or kept running while the
shut-off device is closed.
5.4
Electrical connection
Electrical connection of the pump must be
carried out by skilled personnel only!
The connecting diagramm of the motors is
shown inside the terminal box cover.
Apart from the faultless electrical installation
required (taking into account appropriate guide-
lines and VDE regulations), serious consideration
is necessary of the pump's direction of rotation
(flow direction), which is shown by an arrow on
the pump casing.
The electric motor always needs a protective
motor switch (except for versions with coil protec-
tion contacts or posistors, serving for the direct
motor switch-off). Operating without a protective
motor switch on the input side that is properly set
(at a rated current of IN) shall invalidate any
claims for compensation of damages.
The rotating direction of the shaft as well as
the flow direction of the gas is marked by
arrows at the pump casing.
CAUTION
Wrong direction of rotation leads that pump
gets damaged!
5.5
Operation modes
5.5.1 Open circulation cooling
(standard operation under normal conditions)
The setting up is per illustr. 3a. The operating
liquid B consists of clean liquid F and circulat-
ing liquid U. Liquid similar to clean liquid F
added, leaves the liquid separator as dis-
charge liquid A through the liquid discharge
U
A
. The pressure of clean liquid should exceed
max. 0,2 bar the pressure at the pump dis-
charge nozzle resp. in the liquid separator.
5.5.2 Closed circulation cooling
The closed circulation cooling is applied for
operating liquids, which have due to their
characteristics to remain in the circulatory
process or which may not get in touch with the
cooling medium, or where corrosive , hazard-
ous or highly combustible gases are delivered.
The setting up is per illustr. 4a. At connection
U
A
a shut-off device will be attached. The
operating liquid B consists of circulation liquid
U in the circulating pipe I
U
, a liquid ring vac-
uum pump P
B
has to be mounted, if the vac-
uum pump is running more than 5 minutes
without considerable pressure difference
between suction and discharge nozzle.
The heat exchanger W has to dissipate about
85 % of the motor power and possibly arising
condensation heat. The heat exchanger W