Setra System Model 370 - Manual (Page 16)

3.7 USING THE TARE AND ZERO FUNCTION
The TARE function on the Model 370 gives you a way of setting the
displayed reading to zero or of subtracting a specified offset so that you
can monitor changes in pressure relative to a known starting point. This is
done by creating a tare value which will be subtracted before each up-
dated reading is displayed.
To set the display to zero, press ZERO. The gauge will save the reading in
the display as the tare value, and will subtract that value from every sub-
sequent reading before displaying it.
To subtract an offset from the display, enter the amount of the offset and
press ZERO.
To add an offset to the display, press "-", then enter the amount of the
offset and press ZERO.
To restore the normal display, press "-", then press ZERO. The gauge will
set the tare value to zero and resume displaying pressure in whatever
engineering units are selected.
If you enter a number which will result in a reading requiring more
digits than are available in the display, the display will show "OFLO".
Press CLEAR to resume normal display.
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