Submerged Installation On Auto-Coupling; Dry Installation; Submerged Installation, Portable; Pump Controller - Grundfos SEN series Montage- Und Betriebsanleitung

4.1 Submerged installation on auto-coupling

Pumps for permanent installation can be installed on a stationary
auto-coupling and operated completely or partially submerged in
the pumped liquid.
1. Drill mounting holes for the guide rail bracket on the inside of
the pit and fasten the guide rail bracket provisionally with two
screws.
2. Place the auto-coupling base unit on the bottom of the pit.
Use a plumb line to establish the correct positioning. Fasten
the auto-coupling with expansion bolts. If the bottom of the pit
is uneven, the auto-coupling base unit must be supported so
that it is level when being fastened.
3. Assemble the discharge pipe in accordance with the generally
accepted procedures and without exposing the pipe to distor-
tion or tension.
4. Insert the guide rails into the rings of the auto-coupling base
unit and adjust the length of the rails accurately to the guide
rail bracket at the top of the pit.
5. Unscrew the provisionally fastened guide rail bracket. Insert
the expansion dowels into the guide rails. Fasten the guide
rail bracket on the inside of the pit. Tighten the bolts in the
expansion dowels.
6. Clean out debris from the pit before lowering the pump into
the pit.
7. Fit the guide claw with profile seal to the pump.
8. Slide the guide claw of the pump between the guide rails and
lower the pump into the pit by means of a chain secured to the
lifting bracket of the pump. When the pump reaches the auto-
coupling base unit, the pump will automatically connect
tightly.
9. Hang up the end of the chain on a suitable hook at the top of
the pit and in such a way that the chain cannot come into con-
tact with the pump housing.
10. Adjust the length of the motor cable by coiling it up on a relief
fitting to ensure that the cable is not damaged during opera-
tion. Fasten the relief fitting to a suitable hook at the top of the
pit. Make sure that the cables are not sharply bent or pinched.
11. Connect the motor cable and the monitoring cable, if any.
Note: The end of the cable must not be submerged, as water may
penetrate through the cable into the motor.

4.2 Dry installation

Pumps in dry installation are installed permanently in a pump
room.
The pump motor is enclosed and watertight and will not be dam-
aged if the installation site is flooded with water.
1. Mark and drill mounting holes in the concrete floor.
2. Fit the bracket or base stand to the pump.
3. Fasten the pump with expansion bolts.
4. Check that the pump is vertical/horizontal.
In order to facilitate service on the pump, isolating valves should
be fitted on either side of the pump.
5. Fit the suction and discharge pipes and isolating valves, if
used, and ensure that the pump is not stressed by the pipe-
work.
6. Adjust the length of the motor cable by coiling it up on a relief
fitting to ensure that the cable is not damaged during opera-
tion. Fasten the relief fitting to a suitable hook. Make sure that
the cables are not sharply bent or pinched.
7. Connect the motor cable and the monitoring cable, if any.
Note: It is recommended to use a reducer between the suction
pipe and the pump in horizontal installations. The reducer must
be of the eccentric type and must be installed so that the straight
edge is pointing upwards. In this way, the accumulation of air in
the suction pipe is avoided and the risk of disturbance of opera-
tion is eliminated, see fig. 7.
12
0.2 m
Reducer of the eccentric type
Fig. 7 Dry horizontal installation with eccentric reducer

4.3 Submerged installation, portable

1. Fit the ring stand to the pump suction flange.
2. Fit a 90° elbow to the pump discharge port and connect the
discharge pipe/hose.
If a hose is used, make sure that the hose does not buckle and
that the inside diameter matches that of the discharge port.
3. Lower the pump into the liquid by means of a chain secured to
the lifting bracket of the pump. It is recommended to place the
pump on a plane, solid foundation. Make sure that the pump is
hanging from the chain and not the cable.
4. Hang up the end of the chain on a suitable hook at the top of
the pit and in such a way that the chain cannot come into con-
tact with the pump housing.
5. Adjust the length of the motor cable by coiling it up on a relief
fitting to ensure that the cable is not damaged during opera-
tion. Fasten the relief fitting to a suitable hook. Make sure that
the cables are not sharply bent or pinched.
6. Connect the motor cable and the monitoring cable, if any.

4.4 Pump controller

The SEN pumps can be connected to a separate Grundfos pump
controller for level control, which is available as an accessory:
• type LC for one-pump installations and
• type LCD for two-pump installations.
Depending on application, different types of level control equip-
ment can be used.
The LC controller is fitted with two or three level switches:
Two for start and stop of pump. The third level switch, which is
optional, is for high-level alarm.
The LCD controller is fitted with three or four level switches:
One for common stop and two for start of the pumps. The fourth
level switch, which is optional, is for high-level alarm.
When installing the level switches, the following points should be
observed:
1. To prevent air intake and vibrations in submerged pumps, the
stop level switch must be fitted in such a way that the pump
is stopped before the liquid level is lowered below the top of
the pump housing.
As a principal rule for pumps in dry installation, the lowest stop
level must be at least 20 cm above the opening of the suction
pipe, see fig. 7.
2. The start level switch should be installed in such a way that
the pump is started at the required level; however, the pump
must always be started before the liquid level reaches the bot-
tom inlet pipe to the pit.
3. The high-level alarm switch, if installed, should always be
installed about 10 cm above the start level switch; however,
alarm must always be given before the liquid level reaches the
inlet pipe to the pit.
Note: The pump controller must not be installed in potentially
explosive environments.