General Controls - General RHMG650 User Manual

GENERAL CONTROLS

Changing measurement units. By default, the RHMG650 uses Imperial units for all parametric
readouts. To switch to metric units, press the UNIT button. Ambient temperatures and dew points
will then be displayed as °C rather than °F; absolute humidity values will be stated in g/m
than in mg/L; mixing ratios will be displayed in units of g/kg rather than GPP; and barometric
pressures and vapor pressures will be stated in KPa rather than mBAR.
Backlight. The RHMG650 has a green backlight that automatically illuminates whenever any
button is pressed. It will remain on for 30 seconds and then extinguish to extend battery life.
hold. The second press (and hold) initiates shutdown (which is announced by two short beeps).
Storing readings. Pressing and holding the STORE/ENTER button for at least 2 seconds saves the
values shown on the primary and secondary readouts as a pair in the meter's nonvolatile
memory. Each "save" automatically increases by one the Record number indicator—the number
above MEM at the lower left of the LCD. The readings remain in memory, available for recall, after
the meter powers off.
The next section of this manual contains instructions for recalling saved readings.
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As the figure on the left shows, moving the M pointer four
positions to the right (by pressing the UP> button four times)
switches the meter to operate in Ambient pressure mode.
In Dew point measurement mode,
the secondary readout to remind you that the value shown reflects
the dew point temperature, rather than the ambient temperature.
Holding readings. Briefly pressing the ON/OFF HOLD button freezes
both the primary and secondary readouts.
the display to remind you that the readouts are frozen.
To release the hold, briefly press the ON/OFF HOLD button again.
Note: When the RHMG650 is in Hold mode, it takes two separate
presses of the ON/OFF HOLD button to power off the meter. The first
(brief) press (which is accompanied by a short beep) releases the
will appear at the left of
will appear on
3
rather