User Guide

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SET
HI •)
)
LO •)
)
ENABLE
HI LO
SET
HI
HI LO
MEM
HOLD
ALARM (HI 9050 and HI 9051 only)
During the start-up, the alarm is disabled. It
may be enabled or disabled again by press-
ing the ENABLE key. Both the high and low
setpoints are by default set to 25°C (or 77°F).
The alarm is triggered when the measured
value is greater than the high setpoint or lower than the low setpoint.
In such an instance, the corresponding graphics indicator blinks ac-
companied by an audible sound. The beeper may be turned off by
pressing any key except the ON/OFF key (The ON/OFF key will turn
the unit off and clear the memory). It will automatically be reacti-
vated once the alarm condition is cleared. Reactivation is also possible
by turning the alarm off and on again. Note that the setpoint values
will not be affected by the on-off action.
To set the alarm limits, press the SET key. The flashing "HI
•
)
)" and
"LO
•
)
)" alarm indicators request the user to select the limits.
Press the HI key to enter set mode for high
temperature point or the LO key for low tem-
perature limit. If the HI key is chosen, the low
alarm indicator is switched off leaving the "HI"
indicator blinking with its graphics indicator
held static. Enter the setpoint value with the !
and " keys. Holding the keys down enables
rapid change. Exit from the high alarm limit
setting by pressing the SET key for a second
time. The user may now proceed to set the low
alarm limit or return to the measurement mode
by pressing SET again. The setting of low tem-
perature limit works in a similar manner. In
case of improper setpoint entries, a continuous
false alarm beeper will sound.
MEMORY MODE (HI 9050 and HI 9051 only)
There are two modes of operation.
The first is the Memory & Hold function which is
activated by the MEM HOLD key. The measured
temperature is memorized and frozen on the
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MR
∆M
M
∆M
display when this key is pressed. The previously memorized tem-
perature will be overridden in this case. A blinking "M" on the
display indicates the operating mode. Press
the MEM/HOLD Key again to revert back to
regular operating mode.
The next memory function key, MR/∆M,
serves two purposes:
- The first entry enables recall of the latest
memorized temperature. If no data is
found, "---" will be displayed and the
subsequent function will be aborted on
the next key entry. In this mode, the
"M" indicator also appears on the bot-
tom right corner of the LCD.
- The "∆M" symbol indicates the constantly
updated difference between the memory
content and the current temperature be-
ing measured. Calculation is performed by subtracting the
measured value from the memory content, i.e.:
∆M = (M-T)
where M = memory content
T = measured temperature
A negative result therefore represents a lower memorized value.
Press the MR/∆M key once again to exit this mode.
While in the memory mode, other functions such as HI, LO and
Alarm remain active.
LOW BATTERY DETECTION
The instrument stops operating when a low
battery condition is detected. The user is
warned by "Eb" displayed on the LCD.