Versions Without Mains Plug; Start-Up/Shutdown; Initial Start-Up/Subsequent Start-Up; Checks Before Start-Up - Grundfos DMH 28X Instrucciones De Instalación Y Operación

7.5.2 Versions without mains plug

Warning
The pump must be connected to an external clearly
labelled mains switch with a minimum contact gap of
3 mm in all poles.
• Connect the motor to the power supply in accordance with
local electrical installation regulations and the connection
chart on the terminal box cover.
Warning
The specified enclosure class can only be ensured if
the power supply cable is connected with the same
degree of protection.
Observe the direction of rotation!
To protect the motor, install a motor protecting switch
Caution
or motor contactor, and set the bimetal relay to the
rated motor current for the available voltage and
frequency.

8. Start-up/shutdown

8.1 Initial start-up/subsequent start-up

Warning
When dosing dangerous media, observe the
corresponding safety precautions!
Wear protective clothing (gloves and goggles) when
working on the dosing head, connections or lines!
Before removing the dosing head, valves and lines,
empty any remaining medium in the dosing head into
a drip tray by carefully unscrewing the suction valve.
The pump housing must only be opened by
personnel authorised by Grundfos!
Repairs must only be carried out by authorised and
qualified personnel!
Observe the flow direction of valves (indicated by an
Caution
arrow on the valve)!

8.1.1 Checks before start-up

• Check that the rated voltage stated on the pump nameplate
corresponds to the local conditions!
• Check that all connections are secure and tighten, if
necessary.
• Check that the dosing head screws are tightened with the
specified torque and tighten, if necessary.
• Check that all electrical connections are correct.
• Cross-tighten the dosing head screws using a torque wrench.
Torques
Pump model
DMH 280
DMH 281
DMH 283
DMH 285
DMH 286
DMH 287
DMH 288

8.1.2 Oil filling

Note
1. Slacken and remove the oil-filling screw (F).
2. Slowly add the hydraulic oil supplied with the pump through
the oil-filling opening (F) until the oil reaches the mark on the
oil dipstick.
3. Set the stroke-length adjustment knob (L) to "0".
8.1.3 Filling the dosing head for the initial start-up for
As assisting suction for systems without flooded suction, you can
fill the dosing head with dosing medium before the initial start-up:
1. Unscrew the discharge valve (3b).
2. Add the dosing medium to the dosing head (2).
3. Screw the discharge valve (3b) back in.
Note

8.2 Start-up/subsequent start-up of DMH 280

Fill the dosing head for start-up/subsequent start-up, see
section
deaerate the piston flange, see
Filling the dosing head
Torque
[Nm]
Fig. 23 Filling the dosing head
55-60
17-19
Pos.
27-30
1j
50-54
I
80-85
V
50-54
Z
75-80
The pump is factory-checked, and the oil is drained
for shipping purposes. Before start-up, add the
special oil supplied with the pump.
The piston flange is filled with oil for easy start-up.
The stroke-length adjustment knob must only be
adjusted if the gear oil has been added, otherwise
the oil will leak from the piston flange.
systems without flooded suction (DMH 281-288)
Warning
When dosing dangerous media, observe the
corresponding safety precautions!
Wear protective clothing (gloves and goggles) when
working on the dosing head, connections or lines!
Observe the flow direction of the discharge valve
(indicated by an arrow on the valve)!
Filling the dosing head . If the pump does not start,
Deaerating the piston flange
I
1j
Z
Components
Hose
Deaeration nipple
Deaeration screw
Syringe
.
V
23