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tinb21e1 (2016-06)
SET ATM
1) To set the atmospheric pressure reading (also known as the
"span" adjustment), flow nitrogen gas or air into your closed
vacuum chamber to allow the pressure to rise to a known
value above 400 Torr. Alternatively, if your local uncorrected
barometric pressure (air) is known, simply vent your vacuum
system chamber to expose the gauge to the local atmos-
pheric pressure.
2) Go to the
SET ATM
screen. When the desired pressure is
stable, adjust the displayed pressure reading on the
PGE500 to the known value using the
INCR
(increase) or
DECR
(decrease) keys. Press the
SAVE
key to save the
new atmospheric (span) pressure value. For example, if your
known local uncorrected barometric pressure is 760 Torr,
enter 760 in the SET ATM screen. The main pressure mea-
surement screen will now display 760 Torr while the gauge
is at atmosphere.
It is good practice to perform the sequence of checking and
adjusting span (ATM) then zero (VAC) and then, finally re-
checking the span setting to ensure that the circuitry is
properly balanced for use in measuring pressure throughout
the intended measurement range.
SP1 ON and SP2 ON
[Factory default = 100 mTORR]
These setpoints correspond to the pressures at which the relays
will turn on (energize). The relays will turn on when the pressure
is below the programmed pressure value. If you are unable to
increase the values of SP1 ON or SP2 ON , you must first go to
SP1 OFF or SP2 OFF and increase those values to a number
higher than the values of SP1 ON or SP2 ON you are trying to
set.
Summary of Contents for PGE500
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