DAB KDN Bedienungsanleitung Seite 46

8. REGULATING THE SET
8.1. CALIBRATION OF THE PRESSURE SWITCHES
Standard EN 12845 – UNI 10779 contemplates two pressure switches for each pump, each pressure switch with
normally closed contacts connected in series.
Opening any one of the two pressure switches causes the pump to start.
If you wish to obtain a calibration of the pressure switches different from that performed in the factory, during testing
of the pump set follow the instructions below, considering:

the type of pressure switch installed in the pump set,

the pressure limits indicated on the data plates of each pump,

the limit indicated by standard EN 12845 – UNI 10779 according to which the two pressure switches must be
calibrated in such a way as to start the pump at a value pump pressure with delivery closed x 0.8.

In the case of sets with two pumps, the second pump will be started at a value pump pressure with delivery
closed x 0.6.
Danfoss pressure switch type KP
Slacken the 2 screws and remove the cover.
Remove the blocking metal plate fitted on top of the regulating
screws.
Set the upper pressure limit on the START-STOP regulating
scale (marked RANGE), turning the cross-headed screw.
Then set the lower pressure limit using the differential scale
(marked DIFF), turning the hexagonal head screw.
Replace the blocking metal plate.
Replace the cover and tighten the 2 screws.
Klockner Moeller pressure switch type MCS
Slacken the 4 screws and remove the transparent cover.
Slacken and remove the locking screw "B" positioned in one
of the 12 holes in the regulating knob "A". (figure 1)
When the regulating knob "A" is turned clockwise, the pump
starting and stopping pressures are increased at the same time.
When it is turned counter-clockwise they are decreased. (figure
2)
When the regulating knob "A" is pressed and turned counter-
clockwise, the differential between the starting and the
stopping pressure of the pump is increased (the starting
pressure decreases while the stopping pressure remains fixed).
When the regulating knob "A" is pressed and turned
clockwise, the differential is decreased. (figure 3)
Replace and tighten the locking screw "B" in the hole in the
regulating knob "A" that is most aligned with one of the two
threads under the knob. (figure 4)
Replace the transparent cover and tighten the 4 screws.
9. COMPENSATING ELECTROPUMP
9.1. The pump sets may be provided with a self-priming compensating pump, JET models, connected to the delivery
manifold by means of a check valve and an interception ball valve.
Instead the suction, as in any pump of a set according to standards EN 12845 – UNI 10779, is kept independent.
Keep the pressure switch that controls the compensating pump always calibrated with starting and
9.2.
stopping pressures higher than the others. This is indispensable in order to allow this pump to perform
its task of compensating small falls in pressure in the system before starting the main electropumps and
motor pump.
10. MAINTENANCE
10.1. All our sets are subjected to strict testing of both the electrical and the hydraulic part.
It is unusual for malfunctions to occur, unless due to external or completely accidental causes.
ENGLISH
Start/Stop
(RANGE)
42
Differential
(DIFF)