En
gl
is
h (
G
B)
16
9.3 Direction of rotation
All single-phase pumps are factory-wired for the
correct direction of rotation.
Before starting up three-phase pumps, check the
direction of rotation.
An arrow on the stator housing indicates the correct
direction of rotation.
If the direction of rotation is wrong, interchange any
two of the phases in the power cable.
See fig.
or
.
Checking the direction of rotation
Check the direction of rotation in one of the following
ways every time the pump is connected to a new
installation.
Procedure 1:
1. Start the pump and check the flow of liquid or the
outlet pressure.
2. Stop the pump and interchange any two of the
phases in the power cable.
3. Restart the pump and check the quantity of liquid
or the outlet pressure.
4. Stop the pump.
5. Compare the results taken under points 1 and 3.
The connection which gives the larger quantity of
liquid or the higher pressure is the correct
direction of rotation.
Procedure 2:
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.
3. If connected correctly, the pump will jerk in the
opposite direction of the direction of rotation. See
fig.
4. If the direction of rotation is wrong, interchange
any two of the phases in the power cable. See
fig.
Fig. 12
Jerk direction
10. Maintenance and service
Before carrying out maintenance and service, flush
the pump thoroughly with clean water. Rinse the
pump parts in water after dismantling.
The pump may be started for a very short
period without being submerged to check
the direction of rotation.
The impeller rotates clockwise when the
pump is viewed from above. When started,
the pump will jerk in the opposite direction
of the direction of rotation.
TM
06 60
42 031
6
DANGER
Electric shock
Death or serious personal injury
- Before starting work on the pump, make
sure that the fuses have been removed
or the main switch has been switched
off. Make sure that the power supply
cannot be accidentally switched on.
WARNING
Crushing of hands
Death or serious personal injury
- Make sure that all rotating parts have
stopped moving.
Except for service on the pump parts, all
other service work must be carried out by
Grundfos or a service workshop
authorized by Grundfos and approved for
servicing explosion-proof products.
If the pump is inactive for long periods of
time, we recommend that you check the
function of the pump.
Service videos can be found in Grundfos
Product Center at www.grundfos.com.
