9.3 Direction of rotation
The pump may be started for a very short period
Note
without being submerged to check the direction of
rotation.
Check the direction of rotation before starting up the pump.
An arrow on the top cover indicates the correct direction of
rotation. Correct direction of rotation is clockwise when viewed
from above.
When started, the pump will jerk in the opposite direction of the
direction of rotation, see fig. 17.
Checking the direction of rotation
The direction of rotation should be checked in the following way
every time the pump is connected to a new installation.
Procedure
1. Let the pump hang from a lifting device, e.g. the hoist used for
lowering the pump into the pit.
2. Start and stop the pump while observing the movement (jerk)
of the pump. If connected correctly, the pump will rotate
clockwise, i.e. it will jerk counter-clockwise. See fig. 17.
3. If the direction of rotation is wrong, interchange any two of the
phases in the power supply cable. See fig.
Fig. 17 Jerk direction
10. Maintenance and service
8
or 12.
Before carrying out maintenance and service, it must be ensured
that the pump has been thoroughly flushed with clean water.
Rinse the pump parts in water after dismantling.
For horizontal, dry-installed pumps, a special lifting bracket can
be ordered to ease the lifting of the pump. See the service
instruction on www.grundfos.com.
Warning
Before starting work on the pump, make sure that the
fuses have been removed or the mains switch has
been switched off. It must be ensured that the power
supply cannot be accidentally switched on.
Make sure that all protective equipment has been
connected correctly.
Warning
Before starting work on the pump, make sure that the
mains switch has been locked in position 0.
All rotating parts must have stopped moving.
Warning
Maintenance work on explosion-proof pumps must
be carried out by Grundfos or a service workshop
authorized by Grundfos.
However, this does not apply to the hydraulic
components, such as pump housing, impeller, etc.
Warning
The cable must only be replaced by Grundfos or a
service workshop authorized by Grundfos.
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