11
ENGLISH
This situation can also occur if the pump runs dry, pumps down
to a lower lever than that shown in the installation drawing, or
runs in "snore" mode during the daily test run.
In these cases, the pump housing must be ventilated by un-
screwing the "LUFT" sealing screw.
SERVICING
Maintenance and inspection of this product must be carried
out in accordance with EN 12056-4 and EN 60074-19.
To ensure continued reliability of service, we recommend that
you take out a service contract.
WARNING!
Before carrying out any works: disconnect the pump and the
controls from the mains and take steps to ensure that it cannot
be emergized again.
WARNING!
Check the mains cable for signs of mechanical and chemical
damage. Damaged or kinked cables must be replaced.
NOTICE!
When using a chain to lift the pump, please observe
the relevant national regulations regarding accident preventi-
on. Lifting gear must be checked regularly by an expert in ac-
cordance with the legal regulations.
NOTICE!
Motors in the Ex-range conform to the "flameproof
enclosures" ignition protection category. Maintenance works
that affect the explosion protection may only be carried out by
authorised specialists or by the manufacturer. When carrying
out repairs, all areas next to flameproof gaps must be checked
for damages and, if necessary, replaced by genuine parts.
Oil check
The drain plug is labelled "OEL". In order to check the mechani-
cal seal, the oil, including any residue, must be drained from
the oil reservoir and collected in a clean measuring container.
•
If the oil is contaminated with water (milky), an oil change
must be carried out. Check again after a further 300 operat
-
ing hours, but at the very latest after 6 months!
•
However, if the oil is contaminated with both water and pol-
lutants, then not only the oil must be replaced, but the me-
chanical seal as well.
For monitoring the oil reservoir, it is also possible to retrofit the
electrode of our "DKG" or "DKG-Ex" seal leak control device in
place of the "DKG" sealing screw.
Changing the oil
To ensure operational liability, the first oil change should be
carried out after 300 operating hours, with further oil changes
carried out after every 1000 operating hours.
If the number of operating hours is very low, an oil change
should still be carried out at least once a year.
If wastewater with strongly abrasive constituents is being
pumped, the oil changes should be carried out at correspond-
ingly shorter intervals.
Use HLP hydraulic mineral oil, viscosity class 22 to 46, e.g. Mo-
bil DTE 22, DTE 24, DTE 25, to replace the oil in the oil reservoir.
The quantity of oil required is 1700 cm³.
NOTICE!
The oil reservoir may only be filled with the specified
quantity of oil. Overfilling will result in the pump being rendered
inoperable.
Cleaning
To clean the impeller and the spiral housing, simply remove the
4 hexagonal screws and lift the motor unit off the spiral hous-
ing.
CAUTION!
Worn impellers can have sharp edges.
NOTICE!
If the wrong screws are unscrewed, the oil will run out
of the oil reservoir.
Tightening torque M
A
for A2 screw materials
for M 6 M
A
= 8 Nm
for M 8 M
A
= 20 Nm
for M 10 M
A
= 40 Nm
for M 12 M
A
= 70 Nm
for M 16 M
A
= 160 Nm
Checking the pump unit
The housing screws for the pump, and the connecting and fix
-
ing screws of the installation must be checked to ensure they
are fixed securely. They should be tightened if necessary.
If the pump performance decreases, or if increasingly loud
noises can be heard during operation, the gap dimension be-
tween the impeller face and the wear plate must be checked
for wear by an expert and replaced if necessary. Nominal di-
mension: 0.5 - 0.8 mm.
Adjust the impeller gap
1. Block the impeller.
2. Loosen the central impeller screw located in the impeller
hub.
3.
Loosen the impeller by knocking it gently with a hammer.
4. Tighten the impeller screw until it is “hand tight”.
5. Adjust the impeller gap by pulling the impeller down to the
nominal dimension 0.5 - 0.8 mm.
6. Block the impeller again and tighten the impeller screw to
160 Nm.
The maximum adjustment possible is 3 mm
Replace the wear plate
1. Loosen the four cylinder head screws on the wear plate on
the lower pump case.
2. Take out the old wear plate with the seal.
3.
Clean the wear plate seat and insert the new wear plate with
a new seal.
