Honeywell Fema DWAM Series Assembly And Operating Instructions Manual page 18

2. Pressure monitors with adjustable switching difference DWAMV...
2.1 Technical data as for 1.1
2.2 Electrical connection as for 1.2
2.3 Pressure connection as for 1.3
2.4 Setting
On spindle each is available for setting the switch pressure and the switching difference.
Both spindles are arranged concentrically. The outer spindle with larger diameter influences the
upper switching point, the switching difference and thus the lower switching point, is changed
with the small grub screw located internally.
The action direction is indicated by
the arrow direction.
Setting sequence
a) Upper switching point (with increasing pressure),
with outer spindle, according to scale or pressure
gauge
b) Switching difference (with decreasing pressure),
with small, internal grup screw, results in lower
switching point.
When the switching difference is changed, the
upper switch-off point remains unchanged, the
lower switching point is shifted by the
switching difference.
RSP = SP – xd
SP = switching point
xd = switching differences (hysteresis)
RSP = switch back point
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