Commissioning; Checks Before Start-Up; Start-Up; Operation - Grundfos DMX 227 Installation And Operating Instructions Manual

7. Commissioning

7.1 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.

7.2 Start-up

After initial start-up and after each time the
diaphragm is changed, tighten the dosing head
screws.
Caution
After approximately 6-10 operating hours or two
days, cross-tighten the dosing head screws using a
torque wrench.
Maximum torque: 70-80 Nm.
7.2.1 Filling with gear oil
The pump has been tested in the factory, and the oil has been
drained prior to shipping. Before starting, fill the pump with the
supplied special oil as follows:
1. Make sure that the pump is switched off.
2. Slacken and remove the oil-filling screw with oil dipstick.
3. Slowly add the gear oil through the oil-filling opening until the
oil reaches the mark on the oil dipstick.
– Gear oil for single pumps: 5.0 litres.
– Gear oil for double pumps: 7.5 litres.
4. Switch on the pump.
5. Switch off the pump after approx. 10 minutes, check the oil
level, and add oil, if necessary.
6. Refit the oil-filling screw with dipstick.
7.2.2 Starting the pump
1. Switch on the power supply.
2. Pumps with frequency converter: Set the dosing rate to
100 %. See installation and operating instructions for the
frequency converter and section
flow using a frequency converter
The pump is now ready for operation.
8.3 Adjustment of dosing
.

8. Operation

In the event of a diaphragm leakage, the dosing
liquid may leak out of the hole in the intermediate
flange between the pump and the dosing head. The
parts inside the housing are protected from the
dosing liquid for a short time (depending on the type
Caution
of liquid) by the housing sealing. It is necessary to
check regularly (daily) if liquid is leaking out of the
intermediate flange. For maximum safety, we
recommend the pump version with diaphragm
leakage detection.

8.1 Description of the pump

Fig. 12 DMX 227
Pos. Components
1 Motor
2 Frequency converter
3 Worm wheel
4 Eccentric
5 Tappet
6 Support disk
7 Dosing diaphragm
8 Dosing head
9 Suction valve
10 Pressure valve
Functional principle
• Oscillating positive displacement pump with electric drive,
mechanical diaphragm deflection, and constant stroke length.
• Following reduction of the motor speed by a worm gear, the
rotation of the drive is converted into the suction and
compression movement of the diaphragm by means of an
eccentric and tappet. A defined volume (stroke volume) of the
dosed medium is thus sucked into the dosing head via the
suction valve, and displaced into the dosing line by the
discharge valve.
• The dosing flow can be adjusted in the range 1:10 if a
frequency converter is installed.
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