Richter MPB 25-25-115 - Manual (Page 12)

Series MPB, close-coupled design Page 12
9240-050-en Revision 05
TM 7345 Edition 10/2008
5.7 Drive
The power consumption of the pump at the operating
design point is specified in the data sheet and works
certificate. If the operating design point was not known
when the pump was dispatched, the power
consumption can be read off the appropriate
performance curves. The max. density, the max.
viscosity and a safety margin are to be allowed for.
Care must be taken when selecting the motor size to
ensure that the excess power is not too great. During
start-up the magnetic drive could otherwise stop.
The magnetic drive rating at a nominal speed of 2900
rpm is given in the pump data sheet.
If the motor power exceeds this rating, it is necessary
to check the stoppage of the magnetic drive.
The same also applies if the required drive rating
exceeds 80 % of the magnetic drive rating.
Consult Richter if necessary.
Different operating data can be achieved without
changing the pump through the use of different
speeds, e.g. by means of a frequency converter.
The pump with base plate and motor is illustrated in
the installation drawing.
The operating manual of the motor manufacturer
must be observed.
A motor with a valid ATEX certificate is to be
used if employed in zone 1 and 2.
5.8 Electric connection
Only have the electric connection performed
by a qualified electrician. Compare the
available mains voltage with the information
on the type plate of the motor and select a
suitable circuit.
It is urgently recommended to use motor protection
facilities (motor protection switch).
In potentially explosive areas IEC 60079-14
must also be observed for the electrical
installation.
It must be ensured that the pump is grounded
at the housing 100.
This can be achieved in the simplest case by
using of toothed-lock washers or contact discs if the
substructure itself is grounded.
Otherwise, grounding must be ensured by other
means, e.g. cable bridges.
Units supplied by Richter (pump and base plates) are
to be grounded using suitable devices on the base
plate.
6 Commissioning / Shutdown
6.1 Initial commissioning
Normally, the pumps have already been test-run with
water. Unless special agreements have been made,
there could still be residual amounts of water in the
pump. This must be noted in view of a possible
reaction with the medium.
6.1.1 Filling the pump housing
Check to see whether the screws on the suction
flange, discharge flange, housing flange and drain
flange are tightened. For screw tightening torques
see Section 1.1.
Open the suction line fully so that the medium can
flow into the pump.
Open the discharge valve so that the air in the
pump can escape.
If air cannot be vented into the discharge line, e.g.
a drop in pressure in this line is not permitted,
venting must be performed upstream of the
discharge valve.
Monitor the venting operation until no air but only
liquid emerges.
Close the discharge valve again until
only the minimum flow rate is obtained
after the motor has been started.
6.1.2 Start-up
Check the direction of rotation of the motor with a
rotary field instrument.
As viewed from the motor, the direction of rotation
of the pump is clockwise. See also the direction
of rotation arrow of the pump.
If no rotating field instrument is available, the
motor may also be activated briefly, with the
pump filled, so that it does run up. You can
observe the direction of rotation through the fan hood.
The pump must not run dry during the check
of the direction of rotation.
The pump must be completely filled with liquid. The
maximum admissible flow rate must not be exceeded.
Otherwise the plain bearings can run dry in
both cases.
Switch the motor on.
Set the desired flow by opening the discharge
valve.
When the motor is running but the pump is not
conveying, this means that the magnetic drive
has stopped.
Switch motor off immediately in order to prevent
overheating of the magnet assemblies.