Check Calibration; Maintenance; Service - Grundfos DME 12 Montage- Und Betriebsanleitung

6.3 Check calibration

In check calibration, the calibration value is calcu-
lated by reading the consumption of chemical in a
specific period and comparing this with the number
of dosing strokes performed in the same period.
This calibration method is very accurate and espe-
cially suitable for check calibration after long periods
of operation or if direct calibration is impossible. The
calibration can for instance be carried out when the
chemical tank is replaced or filled.
To carry out a check calibration, proceed as follows:
1. Stop the pump by pressing the
2. Read the counter and note the number of dosing
strokes, see section 4.16.
3. Read and note the quantity in the chemical tank.
4. Start the pump by pressing the
it run for at least 1 hour. The longer the pump is
operating, the more accurate the calibration will
be.
5. Stop the pump by pressing the
6. Read the counter and note the number of dosing
strokes, see section 4.16.
7. Read and note the quantity in the chemical tank.
8. Calculate the dosed quantity in ml and the
number of dosing strokes performed during the
operating period.
9. Calculate the calibration value as follows:
(dosed quantity in ml/dosing strokes) x 100.
10. Set the calculated value in the calibration menu
like for indirect calibration, see section 6.2.
28

7. Maintenance

The pump is maintenance-free. However, it is recom-
mended to keep the pump clean.
The dosing pump is produced according to the high-
est quality standards and has long life. The pump in-
corporates wear parts such as diaphragm, valve seat
and valve balls.
To ensure long life and to reduce the risk of distur-
bance of operation, visual checks should be carried
out regularly.
It is possible to order dosing heads, valves and dia-
button.
phragms in materials which are suitable for the spe-
cific liquid to be pumped. See the product numbers
at the end of these instructions.

8. Service

button and let
Before returning the pump to Grundfos for service,
the safety declaration at the end of these instructions
must be filled in by authorized personnel and at-
button.
tached to the pump in a visible position.
Note: If a pump has been used for a liquid which is
injurious to health or toxic, the pump will be classi-
fied as contaminated.
If Grundfos is requested to service the pump, it must
be ensured that the pump is free from substances
that can be injurious to health or toxic. If the pump
has been used for such substances, the pump must
be cleaned before it is returned.
If proper cleaning is not possible, all relevant infor-
mation about the chemical must be provided.
If the above is not fulfilled, Grundfos can refuse to
accept the pump for service. Possible costs of re-
turning the pump are paid by the customer.
The safety declaration can be found at the end of these
instructions (only in English).
Note: The replacement of the supply cable must be
carried out by an authorised Grundfos service work-
shop.