Stroke-Length Adjustment; Adjustment Of Stroke Rate Using A Frequency Converter; Using The Ar Control Unit; Operation With Other Electronics - Grundfos DMX 226 Notice D'installation Et De Fonctionnement

8.4 Stroke-length adjustment

Warning
Wear protective clothing (gloves and goggles) when
working on the dosing head, connections or lines!
Adjust the stroke length only while the pump is
Caution
running!
The zero point (no dosing) of the dosing pump is factory-set to a
counterpressure of 3 bar. See section
If the operating counterpressure at the injection unit deviates
considerably from this value, it is advisable to readjust the zero
point to obtain more precise values.
1. Install a graduated pipe at the suction valve.
– If such a pipe is not available, insert the suction line into a
graduated measuring jug.
2. Start the dosing pump.
3. Set the dosing flow to 15 %.
4. For pumps with tank-empty indication, remove the electric
plug of the tank-empty indication.
5. Remove the locking screw (A) from the stroke-length
adjustment knob (8) using a screwdriver. See fig. 19.
6. Turn the adjustment knob slowly clockwise (towards the zero
point) until the medium level stops falling in the measuring jug
or pipe.
7. Remove the plug with a small screwdriver without changing
the position of the adjustment knob and unscrew the
cheese-head screw together with the flat spiral spring.
8. Gently pull off the adjustment knob and fit it on the adjusting
spindle so that the zero line on the scale and the mark on the
adjustment knob coincide.
9. Screw in the cheese-head screw and the spiral spring until the
spring is preloaded, but does not block. Even when adjusted
to 100 %, the spring of the adjustment knob must remain
preloaded.
10. Insert the locking screw (A) using a screwdriver and tighten
gently.
Fig. 20 Stroke-length adjustment
13. Dosing curves .
8.5 Adjustment of stroke rate using a frequency
converter
If a frequency converter is connected, the stroke rate can only be
adjusted in the range 10-100 % of max. stroke rate.
See installation and operating instructions for the frequency
converter!
Warning
Observe the manufacturer's instructions!
The connections must be carried out according to
these instructions.
Settings of frequency converter when used with Grundfos
dosing pumps
Pay special attention to the following parameters of the frequency
converter:
• P013 (maximum motor frequency):
– Set the frequency converter to maximum 100 Hz.
– Due to this setting, the maximum stroke frequency of the
pump cannot be exceeded.
• P086 (motor current limit):
– Do not change the default setting (150 %).
– The motor is protected by a PTC resistor. Therefore,
this parameter is not necessary.
• P081 - P085 (motor data):
– Set these parameters to the values stated on the motor
nameplate.
– Observe the manufacturer's instructions!

8.6 Using the AR control unit

When using the AR control unit, observe the installation and
operating instructions supplied with the unit in addition to the
instructions in this manual.

9. Operation with other electronics

First refer to the general section
Caution
section only describes the additional functions.

9.1 Electronic version stroke sensor

Pump type with inductive-proximity switch of two-wire design
according to NAMUR DIN 19234 for signalling the strokes.
The sensor can be installed in potentially explosive atmospheres
if PTB-approved isolating switching amplifiers with an intrinsically
safe control circuit [EExia] or [EExib] are connected. The sensor
can be used up to zone 1 depending on the isolating amplifier.
The specifications in the declaration of conformity for the isolating
amplifier must be observed.
Supply voltage U : 7.7 to 10 V.
B
8. Operation . This
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