
SWK
page 6 SWK 12/03
8. Operation / Configuration / Adjustments
The commissioning of these units is prohibited in machines (as long as the
guidelines 89/392/EWG remain enforced), which do not comply with these
guidelines.
The unit is supplied in 'ready for operation' condition. The switching point is
adjusted on the lowest scale value.
8.1. Adjustment of Limit-Value (SWK-1...)
•Loosen the knurled nut on reed contact.
•Adjust the marking on the contact for the desired value on the scale. In this
position the knurled nut should be tightly screwed.
8.2. Adjustment of Limit-Value (SWK-2...)
•Loosen the knurled nut on reed contact.
•Connect a suitable continuity-tester on cable ends.
•Case 1: On an installed unit
•Open the supply line, and let the flow-medium enter slowly, till the pointer
display shows the desired flow value, at which the rising flow should operate
the switch(The value for the decreasing flow lies below due to the hysteresis).
•Case 2: On an upgraded unit the adjustment may be performed by lifting the
float with a suitable tool.
•Switch-housing is dislocated from top to bottom, till the reed contact just
closes (electrical continuity). In this position, align the contact by rotating the
knurled nut.
The unit is now adjusted and ready for operation.
On correct adjustment, the limit-value contact performs bistable action. That
means, even on crossing the adjusted limit-values, the contact remains closed.
Hysteresis
Hysteresis is an indication of difference between switch-on and switch-off points
of a contact. The average hysteresis corresponds to a float-centre movement of
about 3 mm.