Shortridge Instruments AIRDATA ADM-880C, Руководство по эксплуатации

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ADM-880C 07/20/09 22
5.6.2 AUTOMATIC READINGS
Select the AUTO (automatic) reading mode by pressing ALT / READ. The meter will display [AUTO READY]. When the
READ/SELECT key is pressed again, the meter takes continuous, repeated readings. Readings will continue until the user
executes a halt by pressing the READ/SELECT key again. The meter then displays [HALT]. Automatic readings may be
stored in memory by pressing ALT / READ / STORE as described in Section 5.7.1.1 STORE ALL. The meter will store
continuous, repeated readings until the READ/SELECT key is pressed to halt the readings.
5.6.3 TREND READINGS
Select the TREND reading mode by pressing ALT / READ / ALT / READ. The meter will display [TREND RDY]. When
the READ/SELECT key is pressed, the meter will take continuous measurements at the rate of approximately one every
second. Readings will continue until the user executes a halt by pressing the READ/SELECT key again. The meter will
then display [HALT]. Trend readings reduce accuracy to gain faster readings. TREND measurements are as accurate as
they can be in one second, but they are less accurate than MANUAL and AUTO readings. Accurate measurements require
sufficient time, one to eight seconds depending on the signal level, to properly evaluate the analog signal being sensed.
Also, the last digit in all flow, velocity, and differential pressure readings made in the TREND mode is rounded to the nearest
five units (the last digit will be either a zero or a five). Absolute pressure and temperature readings in the TREND mode
are not rounded. TREND readings are designed for damper adjustments and other situations where quick feedback is
preferable to a longer, more accurate measurement. Trend readings may not be stored in memory. The meter displays
an arrow during TREND mode readings to indicate the rate and direction of change for the measured values. A vertical
up or down arrow indicates a rapid rate of change. A diagonal arrow indicates a slower rate of increase or decrease.
5.6.4 SELECT
The READ key also functions as the SELECT key. Press READ / SELECT to confirm a selection when the letter “s” is
displayed at the right of a display.
5.7 STORE KEY
The STORE key is used to select a STORE mode, CLEAR all readings in memory, and CHANGE memory. The options
under CHANGE memory include exiting the current memory group and selecting a new memory group, erasing a stored
reading, and replacing a stored reading.
5.7.1 STORE MODE
Press the STORE key repeatedly to access the three memory options:
Store All All subsequent readings are saved in memory.
Store Last Reading is displayed, user chooses to store reading in memory or discard.
Store Off Readings are taken in MANUAL or AUTO read mode and are not stored in memory.
There are restrictive relationships between the reading options and the memory modes:
Reading Modes Store Off Store All Store Last
Manual Allowed Allowed Allowed
Automatic Allowed Allowed Not Allowed
Trend Required Not Allowed Not Allowed
Timed Not Allowed Required Not Allowed
The memory can be divided into 25 different memory groups, lettered from A to Z (the letter O is not used because of
possible confusion with zero). Each memory group can store as few as a single reading, or as many as necessary, up to
the maximum of 2000 total readings across all groups. A single memory group may be used, or as many different memory
groups as needed. Group letters may be skipped or selected in any order. However, if many memory groups are being
used, the maximum number of readings may decline slightly to between 1950 and 2000. The group letter is displayed as
the third character in the reading sequence number, for example [01A .0205].
The measurement mode may be changed while either the STORE ALL or STORE LAST modes are active. Any memory
group may contain any or all types of measurements. For example, the results of a pitot tube velocity traverse of a duct
may be stored as readings 01A through 09A. The user may then press the MODE key to change the measurement mode
to differential pressure. After installing the appropriate accessories, the user may then make and store a static pressure
reading 10A at the site of the duct traverse.
When the number of readings in memory reaches the maximum of 2000, the meter will stop reading and display [STORE
FULL]. Clear the [STORE FULL] display by pressing any key. The meter will exit the STORE mode and display [STORE
OFF]. No further readings can be stored until the memory has been cleared by pressing ALT / STORE. However, while