9
7.2 Electrical installation
The following must be observed:
•
The electrical installation of the booster set must comply with
enclosure class IP54.
•
Make sure that the booster set is suitable for the electricity
supply to which it is connected.
•
Make sure that the wire cross-section corresponds to the
specifications in the wiring diagram.
8. Control panel
The Grundfos Hydro Multi-S booster set can be controlled via the
control panel integrated in the control cabinet. See fig. 4.
Fig. 4
Control panel
9. Start-up
To start up the booster set, proceed as follows:
1. Connect water and power supplies.
2. Close the valve on the discharge side of all the pumps.
3. Prime all pumps, and make sure that the suction manifold and
the suction pipe are primed as well.
4. Check that the tank pre-charge pressure is equal to 0.9 x
cut-in pressure.
5. Switch on the electricity supply.
6. Start the first pump by pressing and holding down the button
for manual operation.
7. Check the direction of rotation of the pump.
If the direction of rotation is wrong, interchange two phases of
the electricity supply.
8. Vent the pump by slowly opening its discharge valve.
9. Repeat the same procedure for the other pumps.
10. Release the booster set for automatic operation by pressing
the button for automatic operation.
10. Operating modes
The operating mode of each pump can be selected with the
dedicated buttons for "Automatic operation", "Stop" and "Manual
operation" as described in section
.
10.1 Manual operation
Manual operation is generally used during commissioning, testing
or for maintenance and service purposes.
To enable manual operation, press and hold down the button for
manual operation.
10.2 Automatic operation
When this operating mode is selected, the pumps operate
automatically according to the system requirements, e.g. the
pressures set on the pressure switches.
•
When a tap is opened, water is drawn from the diaphragm tank
until the tank is empty.
•
When the pressure drops to the first cut-in pressure, the first
pump will start.
•
If the consumption is still increasing, more pumps will be cut in
until the performance of the pumps in operation corresponds
to the requirements.
•
When the water consumption decreases, the discharge
pressure rises to the first cut-out pressure and the pressure
switch cuts out and one pump is stopped.
•
If the consumption is still decreasing, more pumps will be cut
out until the last pump finally fills the diaphragm tank and
stops.
10.3 Dry-running protection
The Hydro Multi-S incorporates dry-running protection to protect
the pumps from running dry. The dry-running protection is
activated by a pressure switch or a level switch connected on the
suction side and then connected to the control cabinet.
Warning
The electrical connection must be carried out by
an authorised person in accordance with local
regulations and the relevant wiring diagram.
Make sure to disconnect the electricity supply
using the mains switch and lock it with a padlock
to ensure that it cannot be accidentally switched
on.
Note
For the electrical connection, please refer to the
wiring diagram supplied with the booster set.
T
M
03
97
20
43
0
7
Pos.
Description
1
LED indication for dry-running alarm
2
Pump number
3
LED indication for fault status
(three-phase pumps only)
4
LED indication for pump running
5
Push-buttons for manual operation
6
Push-buttons for stopping the pumps
7
Push-buttons for automatic operation
8
LED indication for power on
1
2
3
8
4
5
6
7
Caution
Do not start the booster set until the pumps and
the suction pipe have been filled with liquid.
Note
The button for manual operation has no
permanent position. Therefore, keep the button
pressed during the test cycle.
Note
Each pressure switch is related to one pump only
and not necessarily to the same pump when the
pumps alternate after each cycle.
