Electrical Connections; Electric Servomotor (Optional); Installation And Operating Instructions; Electronic Preselection Counter (Optional) - Grundfos DMH 28X Instrucciones De Instalación Y Operación

7. Electrical connections

Make sure that the pump is suitable for the electricity supply on
which it will be used.
Warning
Electrical connections must only be carried out by
qualified personnel!
Disconnect the power supply before connecting the
power supply cable and the relay contacts!
Observe the local safety regulations!
The pump housing must only be opened by
personnel authorised by Grundfos!
Protect the cable connections and plugs against
corrosion and humidity.
Only remove the protective caps from the sockets
that are being used.

7.1 Electric servomotor (optional)

To connect the servomotor to the power supply, see the
installation and operating instructions for the servomotor.

7.2 Electronic preselection counter (optional)

To connect the preselection counter to the power supply, see the
installation and operating instructions for the counter.

7.3 Electrically heated dosing head (optional)

2e
Fig. 20 Electrically heated dosing head
Pos. Component
2e Dosing head, electrically heated
• To connect the temperature controller to the power supply, see
the installation and operating instructions for the electric
temperature controller.
2e1
2e2
2e3
Fig. 21 Temperature controller
Pos. Connections
2e1 Sensor
2e2 Heating
2e3 Power supply
22

7.4 Diaphragm controller (optional)

Warning
Explosion-proof pumps with diaphragm leakage
detection are fitted with a contact pressure gauge in
explosion-proof version.
The pressure gauge must be earthed.
Connecting the earth cable (4u), see fig. 22.
S
5s
4u
U
5u
T
Fig. 22 Diaphragm controller
Pos. Components
S Contact pressure gauge
5s Union nut
6s Contact output
T Ball non-return valve
U Connection piece
2u Deaeration screw
3u O-rings
4u Connection for earth cable
5u Union nut
or locking unit (instead of contact pressure gauge and
2)
its connection)

7.5 Connecting the power supply cable

Warning
Disconnect the power supply before connecting the
power supply cable!
Before connecting the power supply cable, check
that the rated voltage stated on the pump nameplate
corresponds to the local conditions!
Do not make any changes to the power supply cable
or plug!
The assignment between the plug-and-socket
Caution
connection and the pump must be labelled clearly
(e.g. by labelling the socket outlet).
The pump can be automatically started by
Caution
connecting the power supply!
• Do not switch on the power supply until you are ready to start
the pump.

7.5.1 Versions with mains plug

• Insert the mains plug in the mains socket.
6s
3u
2)
2u
3u