Mechanical Seal - Wilo VeroTwin-DPL Einbau- Und Betriebsanleitung

• Heat-resistant power cable must be used for
pumps in systems with water temperatures above
90°C.
• The power cable must be routed in such a way to
avoid any contact with pipework and/or pump/
motor housings.
• Check available mains power supply and voltage.
• Observe motor name plate data.
• Mains power supply fuses: depending on motor
full-load current.
• The pump/installation must be earthed in compli-
ance with the applicable regulations.
• The power wiring diagramm is inside the terminal
box cover (see also Fig. 3).
Terminals must not be connected to a
ATTENTION!
voltage over 7.5V, a higher voltage will
damage the PTC-sensors.
• Mains power supply to the terminal depends on
rated motor power P
the starting method. For the required terminal
bridge connections refer to table below and
Fig. 3.
Figure 3
Motor
power rating
Starting
P 3 kW
2
arrange-
ment
Mains power
3 230 V
~
DOL-Star- -connec-
ting tions (3a)
Y- - Remove
Starting terminal
bridges (3c)
• Comply with respective installation and operating
instructions when wiring to automatic pump con-
trol gear.
6 Commissioning
• Pump, suction and inlet piping must be filled and
properly vented.
The pump must not run dry. Dry-running
ATTENTION!
will damage the mechanical seal!
• In order to avoid noise and damage due to cavita-
tion a minimum inlet pressure must be ensured at
the pump suction port. This minimum inlet pres-
sure depends on the operating conditions and the
duty point of the pump and must be accordingly
calculated. Significant criteria for calculating the
minimum required inlet pressure are the NPSH-
level of the pump at its operating point and the
vapour pressure of the liquid.
Installation and operating instructions Wilo-IPL/-DPL (3-7,5 kW)
, the supply voltage and
2
Motor
power
rating
P 4 kW
2
Mains
power
3 400 V 3 400 V
~ ~
Y-connec- -connec-
tions (3b) tions (3a)
Not possible Remove
terminal
bridges (3c)
• Vent pumps by unscrewing its air vent plugs (Fig.
4, 5, pos. 2.1).
Beware of scalding!
Depending on the fluid temperature and the sys-
tem pressure, if the vent screw is completely loos-
ened hot liquid or gas can escape or even shoot
out at higth pressure.
• Check the direction of rotation by briefly swit-
ching on the pump and make sure that rotation
coresponds with the arrow on the motor (fan
cover or flange). If necessary, correct as follows:
• DOL-Starting: Change any 2 phase wires at the
motor terminals (e.g. L1 and L2).
Y- -Starting: At the motor terminals change
winding start and end terminal connections
respectively of 2 windings (e.g. V1 with V2 and W1
with W2).
• Ensure a minimum flow of about or higher than
10 % of the maximum flow of the pump.
• Check that the current input does not exceed the
valve indicated on the motor data plate.
The pump must not run for longer than 10
ATTENTION!
minutes with a flow rate of Q = 0 m³/h
(closes discharge valve).
Risk of burning / frostbitten if the pump is
touched!
Depending on the operating conditions of the
pump or installation (fluid temperature), the entire
pump can become very hot or very cold.
Keep distance during pump operation!
7 Maintenance
Before starting service or repair work switch off
the plant and secure against unauthorized switch-
ing.
Beware of scalding!
In the event of high temperatures and high system
pressure, the pumps should be allowed to cool
down.

7.1 Mechanical seal

Slight may occur during the running-in period.
Visual leakage checks are however required
weekly. Distinctly visible leakage will require an
exchange of the seal. WILO offers a repair set con-
taining all parts required for an exchange.
Exchange of the mechanical seal (Fig. 4, 5):
• Switch off power supply and secure against unau-
thorized switching.
• Close isolating valves at both pump ports.
• Lower the pressure of the pump by opening the air
vent plugs (pos. 2.1).
Beware of scalding!
In the event of hot liquids,
• Disconnect wires from motor terminals if cable
length is too short for dismantling the motor.
• Unscrew the motor fixing-screws (pos. 4) at
motorflange and lift the motor with impeller and
English
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