Grundfos CH 12, Installation And Operating Instructions Manual

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8
3. Electrical connections
The electrical connections should be carried out in
accordance with local regulations.
The operating voltage and frequency are marked on
the nameplate. Please make sure that the motor is
suitable for the electricity supply on which it will be
used.
Single-phase motors, 1 x 110/220 V, 60 Hz, do not
incorporate motor protection and must be connected
to an approved motor starter.
Other single-phase motors incorporate a thermal
overload switch and require no additional motor pro-
tection.
Three-phase motors must be connected to a motor
starter, the set nominal current of which must corre-
spond to the electrical data on the pump nameplate.
Do not start the pump until it has been filled with liq-
uid.
Connections should be made as shown on the inside
of the terminal box cover.
Choose one of the two cable entries and knock out
the pre-cut disk.
3.1 Checking of direction of rotation
(Three-phase motors)
Arrows on the motor fan cover indicate the correct di-
rection of rotation.
The pump should rotate counter-clockwise when
viewed from the motor end.
To reverse the direction of rotation, switch off the
electricity supply and interchange any two of the in-
coming supply wires.
4. Starting
4.1 Priming
Do not start the pump until it has been filled with liq-
uid and vented.
Booster systems and systems where the liquid
level on the suction side is above the pump inlet:
1. Close the isolating valves either side of the
pump.
2. Remove the priming plug P, fig. 4.
3. Slowly open the suction valve and keep it open
until a steady stream of liquid runs out the prim-
ing port.
4. Close the valve, replace the priming plug and
tighten securely.
5. Open the suction valve.
6. Start the pump and slowly open the discharge
valve until it is fully open.
Fig. 4
Pumping from tanks and wells where the liquid
level on the suction side is below the pump inlet:
1. Close the discharge isolating valve.
2. Remove the priming plug P, fig. 4.
3. Pour water through the priming port. Make sure
that the suction pipe and pump are completely
filled with liquid and vented.
4. Replace the priming plug and tighten securely.
5. Start the pump and slowly open the discharge
valve until it is fully open.
4.2 Frequency of starts and stops
Maximum 100 starts per hour.
5. Operation and maintenance
Under normal operating conditions, the pump does
not require any maintenance.
If the pump has been used for pumping liquids that
may leave impurities in the pump, it should be
flushed through with clean water immediately after
use.
5.1 Frost protection
Pumps which are not being used during periods of
frost should be drained to avoid damage.
Remove the priming and drain plugs P and V, fig. 5.
Do not replace the plugs until the pump is to be used
again.
Fig. 5
Never make any connections in the pump
terminal box unless the electricity supply
has been switched off.
The pump must be connected to an exter-
nal mains switch.
In systems with hot liquids, extreme cau-
tion should be exercised when venting the
pump to eliminate the risk of personal in-
jury caused by escaping water.
P
TM
00
06
92
48
96
P
V
TM
00
06
93
48
96