WIKA A-RB-1, Operating Instructions Manual

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Press SET 1 once more: The new value will be memorised. This is
indicated by 3 dashes "---" appearing for a few seconds and the LED
extinguishes.
Contact function can be selected to HIGH ALARM (meaning make on
rising value), or LOW ALARM (meaning make on falling value). This is
easily achieved by programming the make (SE) value either above or
below the corresponding break (SA) value.
Setting (SE) above (SA) means HIGH ALARM. (SE) will energise the alarm
circuit, which will remain energised until the display figure decreases to
reach the value of (SA).
Setting (SE) below (SA) means LOW ALARM. (SE) will energise the alarm
circuit, which will remain energised until the display figure increases to
reach the value of (SA).
The difference between (SE) and (SA) represents the hysteresis across
make and break points of the contact. (This must not be confused with
any hysteresis across approach of the set points with rising and falling
values. This sort of mechanical delay is not apparent with a digital
instrument).
Both values can be programmed without limitations, as the case
demands. Setting both, (SE) and (SA) at the same values, will automati-
cally create HIGH ALARM function.
The LED's in the upper corners of the SET keys are intended to indicate
the alarm configuration together with the relay status. The left LED, when
lit, indicates energised alarm circuit at HIGH ALARM programmed. The
right LED, when lit, indicates energised alarm circuit at LOW ALARM
programmed.
SET 1 key corresponds to alarm 1, SET 2 key corresponds to alarm 2.
Programming of alarm contacts can be terminated at any time by hitting
the RESET key. In this instance, only such changes are accepted that
have been acknowledged by appearance of "---". Otherwise, previously
set values remain in effect.