Meriam M203 User manual

User’s Manual 9R122-A
June, 2010
M203 Altimeter / Indicated Air Speed Tester
USER’S MANUAL
The Meriam Process Technologies (Meriam) M203 Altimeter / Indicated Air Speed Tester is a
microprocessor based pressure sensing device used to measure pressure 0-900 millimeters
(mm) Hg relative to absolute zero. The handheld is NIST traceable.
When used in Pressure Measure Mode, pressure can be displayed in a variety of engineering
units. Select the ALT / IAS engineering unit and the M203 converts to Altitude Mode for checking
altimeter instruments. Pressing the TARE button from Altitude Mode changes the M203 to Air
Speed Mode for checking air speed instruments.
A timed leak test function is available for Pressure, Altitude and Air Speed Measure Modes. Other
featuresinclude a Min/Max capture, selectable damp rates and field re-calibration.
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Safety Information
Failure to follow all instructions could result in injury.
Read, understand and follow all safety warnings and
instructions provided with this product. Also, meet or
exceed your employer’s safety practices.
In no event shall Meriam be liable for any indirect, special,
incidental, consequential or punitive damages or for any lost
profits arising out of or relating to any services provided by
Meriam or its affiliates. It is not possible for Meriam to identify all
foreseeable uses/misuses, therefore all persons involved in
commissioning, using or maintaining this product must satisfy
themselves that each intended application is acceptable.
Safety Warnings
The table below defines the safety symbols, signal words and
corresponding safety messages used in the manual to identify
potential hazards and are intended to warn persons about
hazards that could result in personal injury or equipment damage.
This is the Read Instruction Manual symbol. This symbol indicates
h that you must read the instruction manual.
This is the Safety Alert symbol. This symbol indicates a WARNING.
Warnings alert you to actions that can cause personal injury or pose
a physical threat. Please read these carefully.
This is the Safety Glasses symbol. This symbol indicates that you
must wear approved safety glasses during the task.
This is the Safety Gloves symbol. This symbol indicates that you
must wear approved safety gloves during the task.
Indicates a potentially hazardous situation which, if
not avoided, will result in death or serious injury.
Indicates a potentially hazardous situation which, if
not avoided, could result in death or serious injury.
Indicates a potentially hazardous situation which, if
not avoided, could result in minor or moderate injury.
Indicates information essential for proper product
installation, operation or maintenance.
Information in this document is subject to change without
notice. Check the Meriam web site (www.meriam.com) for
the latest manual revision.
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Table of Contents
Certification/Safety/Warnings .......................................................1
User Interface ...............................................................................2
1. Keypad Functions ...................................................................2
ON/OFF & BACK KEY ................................................................2
MIN/MAX & UP KEY...................................................................2
TARE & DOWN KEY ..................................................................2
PRGM & ENTER KEY.................................................................3
BACKLIGHT KEY..........................................................................3
2. Zeroing the Manometer ...........................................................4
3. Program Mode ......................................................................8
Units Select ..................................................................................9
ALT / IAS (Altitude / Indicated Air Speed) Mode..................................10
Damp Rate Select ........................................................................12
User Info Select (Accuracy, SW version, Mfr date, SN).........................13
Auto Shut-Off...............................................................................14
Lockout Select..............................................................................15
Header Name ..............................................................................16
Contrast Select............................................................................17
Data Logging ...............................................................................18
Leak Test....................................................................................19
Re-Calibration..............................................................................20
RE-CALIBRATION – 1 Point EDIT and START...................................21
RE-CALIBRATION – 5 Point EDIT....................................................22
RE-CALIBRATION – 5 Point START ................................................23
RE-CALIBRATION – Restore Factory Defaults ...................................24
Specifications...............................................................................25
Changing the Batteries ................................................................26
Service and Calibration................................................................28
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User’s Manual 9R122-A
June, 2010
1
Certification/Safety/Warnings
Fire/Explosion Hazard. This instrument is
not intrinsically safe. DO NOT use in
areas that may contain flammable gas or vapors,
combustible dusts or ignitable fibers where an unintended
spark can cause a fire/explosion.
Do not exceed the Pressure Limits listed
in the Specifications section of this
manual. Failure to operate within the specified pressure
limit could result in minor or moderate injury
Substitution of components may impair
operation and safety.
Disconnect power before servicing.
The product should not be powered
with a combination of new and old
batteries.
The product should not be powered with a
combination of batteries from different
manufacturers.
User must use a wrench on the pressure
manifold when installing user’s 1/8” NPT
fitting. Do not tighten the fitting without using a wrench on the
pressure manifold. Failure to use a wrench on the manifold will
damage the plastic enclosure and void warranty No torque
should be applied to the manifold with respect to plastic
enclosure.
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User Interface
1.
Keypad Functions
ON/OFF &BACK ◄KEY
Turns the manometer on and enters the unit into the Measure Mode. Pressing
the key while in the Measure Mode turns the unit off. It also serves as a
backspace key when editing in the Program Mode. The ◄ key takes the user
out of a programmable register without changing the previous setting. Pressing
this key repeatedly will return the user to the Measure Mode and then shut off
the manometer.
MIN/MAX & UP ▲KEY
In the Measure Mode activates the Min/Max function of the manometer. When
activated the minimum value is displayed on the upper left of the display and
the maximum value on the upper right. This key also deactivates and resets
this function. The ▲ key is used to scroll through the programmable registers
when the unit is in the Program Mode. Once a programmable register is
selected the ▲ key can be used to edit that register.
TARE &DOWN ▼KEY
In the Pressure Measure Mode, toggles on/off the Tare function.
The Tare
function nulls the applied pressure and sets the display value to
“0”. With Tare activated, the letter “T” appears in the lower left of the display.
In the ALT / IAS Measure Mode (selected from Program Mode
under
Units Select menu), the Tare button toggles between ALTITUDE function
and AIR SPEED function.
The ▼ key is used to scroll through programmable registers
when the unit is in
Program Mode. Once a programmable register is selected the ▼ key can be
used to edit that register.
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PRGM & ENTER ►KEY
Puts the manometer into the Program Mode from the Measure Mode. When in
the Program Mode, pressing this key selects the programmable register
to be edited (with prompt for password if Lockout is set). After the register
has been edited, pressing the PRGM key enters the new setting into the
manometer’s non-volatile memory. This key also acts as a forward space ►key
when editing user inputs such as the header name.
BACKLIGHT KEY
The BACKLIGHT key, represented by the standard light bulb symbol,
toggles
the display backlight between on and off.
The backlight consumes additional battery energy. Turn the backlight
off, when
it is not needed, to optimize battery life.
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2.
Zeroing the Manometer
The M203 Precision Smart Manometer is a stable and precise
instrument. However, on occasion the M203 should have a new zero taken.
This is done to remove zero drift that can occur since the manometer was
last zeroed. The M203 can be zeroed only if the new applied zero is within ±1%
FS of the original factory calibration zero. This prevents accidental zeroing at
atmospheric pressure or other relatively high pressures. If outside this
limit a “ZERO RANGE ERROR” message appears and the manometer will not
zero.
The M203 provides three mechanisms for re-zeroing:
1.
Referenced to Absolute Zero: This traditional and preferred method
takes a “snapshot” of the measured pressure when a vacuum of less than 100
microns Absolute is applied to the sensor.
2.
Factory Zero: This method restores the calibration curve to the original
zero taken at the factory. Note that this feature is intended for comparison
purposes, and should not be used for real pressure measurement, as any
zero-drift since shipment will not be accounted for.
3.
User-Adjusted Zero: This method allows the user to enter any pressure
value when a known reference is applied (for example, the local barometric
pressure reading). The manometer will compare its actual measured value
with the entered value, and calculate a new zero reference based on the offset.
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1.
To zero the manometer using Referenced to Absolute Zero,
start with the unit turned OFF and use the following keystroke
sequence:
Keystroke Display
1. Press ON/OFF button.
2. Connect the M203 to a
vacuum source capable of 100
microns absolute or less.
3. Pull a full vacuum
The display briefly shows
the header name and full
scale range in the last
engineering units selected.
The manometer then goes
into the Measure Mode
showing the pressure and
engineering unit.
Display should read close
to zero. (See note on next
page)
4. Press MIN/MAX and TARE
keys at the same time. (See
Figure 1 below.)
Top line o
f
display reads
“ZEROING SOURCE:”
Bottom line of display
reads “REF TO ABS ZERO”
5. Press the PGRM key. Top line o
f
display reads
“ZERO IN PROGRESS”
while bottom line counts
down from 9. Zeroing is
complete when unit returns
to Measure Mode.
Figure 1 NOTE: The M203 can be zeroed only if
the new applied zero is within ˜ 1% FS
of the original factory calibration zero.
If outside this limit a “ZERO RANGE
ERROR” message appears and the
manometer will not zero. Contact the
factory for support in this case.
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2.
To zero the manometer using Factory Zero, start with the unit
turned ON and in Measure Mode. Then use the following
keystroke sequence:
Keystroke Display
1. Press MIN/MAX and TARE
keys at the same time. (See
Figure 1 above.)
2. Press ▲or ▼arrow key until
desired zero function is shown
on the bottom line.
Top line of display reads
“ZEROING SOURCE:” Bottom
line of display reads “REF TO
ABS ZERO”
Bottom line of display reads
“FACTORY ZERO”
3. Press the PRGM key. Zeroing is complete when unit
returns to Measure Mode.
The Factory Zero feature is intended for comparison purposes only. Factory
Zero should not be used as a reference for actual pressure measurement
because zero-drift occurring after shipment would not be accounted for. Use
Referenced to Absolute Zero or User-Adjusted Zero options when re-zeroing is
necessary.
3. To zero the manometer using User-Adjusted Zero, start with the unit
turned ON and in Measure Mode. Then use the following keystroke sequence:
Keystroke Display
1. Apply a known, accurate
pressure source. This may be
true atmospheric pressure from a
reference barometer
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2. Press MIN/MAX and TARE keys
at the same time. (See Figure 1
above.
Top Line of display reads
“ZEROING SOURCE:” Bottom line
of display reads “REF TO ABS
ZERO”
3. Press ▲or ▼arrow key until
desired zero function is shown on
the bottom line.
4. Press the PRGM key.
5. Press any of ▲or ▼arrow key
or the PRGM key to begin editing.
Example: set current pressure value
to 29.5 in Hg @ 0° C Abs.
6. Press the ▲or ▼arrow key to
set the first digit to 0.
Using the ▲arrow key, the
character sequence is 0 – 9, (-)
negative, (.) decimal point. The (-)
sign is used if your location is below
sea level.
7. When the User Adj. Value is
correct press the PRGM key.
Bottom line of display reads “USER
ADJ. ZERO”
Top line of display shows the
current non-zero compensated
pressure value. Bottom line of
display shows the same value,
along with the engineering unit.
Top line of display continuously
updates. Bottom line of display data
is ready for editing; the first
character location is blinking.
Current: xxx.xx
0xx.xx INHG
Cursor flashes to the right of “0”.
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If an error is made use the
back space ◄key to move
the cursor back to the
incorrect digit. Press the
UP ▲or DOWN ▼arrow
keys to correct the value,
8. Continue this process
until the display reads as
shown at right.
Current: xxx.xx
029.50 INHG
9. Press the PRGM key to
enter the final value.
Zeroing is complete when
unit returns to Measure
Mode.
Note that the User Adjusted Zero feature will not accept entries in altitude units
(FEET or METERS). When the current engineering unit is FEET, the User
Adjusted Zero function will automatically prompt for an entry in Inches of Mercury
@ 0º C. When the current engineering unit is METERS, the User Adjusted Zero
function will automatically prompt for an entry in Millimeters of Mercury @ 0º C.
3. Program Mode
The Program Mode is used to configure the manometer for Measure Mode
operation. After the PRGM key is pressed in Measure Mode, the top line of the
display reads “PROGRAM MODE”. The bottom line reads “UNITS SELECT”.
Press the ▲or ▼arrow keys to scroll through the Program Mode to the desired
register. The configurable registers found in the Program Mode are Units Select,
Damp Rate Select, User Info Select, Contrast Select, Data Logging, Leak Test
and Exit. Press the PRGM key to select any of these configurable registers. The
manometer can be put into Program Mode at any time during Measure Mode
operation by pressing the PRGM key. If Lockout is set, the correct code must be
entered when prompted (see the User Info / Lockout section of this manual for
more information on Lockout).
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Units Select
The standard units available on the M203 are:
Inches of Mercury at 0° C (in Hg @ 0° C) (absolute) Millimeters of Mercury at 0° C
(mm Hg @ 0° C)
(absolute)
PSI (absolute)
Mbars (absolute)
Bars (absolute)
kPa (absolute)
Torr (absolute)
ALT / IAS - selecting this unit gives access to English units.
(knots, MPH and Feet) or Metric (km/h and Meters)
To change the engineering units the manometer should be “ON” and in Measure
Mode. Then follow these steps:
Keystroke Display
1. Press the PRGM key. Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
2. Press the PRGM key. Top line reads “UNITS
SELECT” and bottom line
shows current engineering unit.
3. Press the ▲or ▼arrow key
until desired engineering unit is
displayed
Engineering units on bottom
line of display change.
4. Press the PRGM key to
select the engineering unit.
Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
5. Press the ▼arrow key Bottom line reads “EXIT”.
6. Press the PRGM key. Display returns to Measure
Mode in new engineering unit.
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ALT/ IAS (Altitude / Indicated Air Speed) Mode
The model M203 is capable of displaying altitude (feet or meters based on “U.S.
Standard Atmosphere 1962” tables) and air speed (knots, MPH or km/h). The ALT
/ IAS Mode is selected from Program Mode in the Units Select menu. Once ALT /
IAS Mode is selected, the M203’s default measurement is altitude. Pressing the
“Tare” key nulls the prevailing barometric pressure and converts the display to air
speed indication. To revert back to altitude the “Tare” key is toggled again.
To set up the M203 for ALT / IAS Mode use the following steps:
Keystroke Display
1. Press the PRGM key. Top line reads “PROGRAM
MODE” and the bottom line
reads “UNIT SELECT”.
2. Press the PRGM key. Top line reads “UNITS
SELECT” and bottom line
shows current engineering
unit.
3. Press the ▲or ▼arrow
key until “ALT/ IAS” is
displayed.
Top line reads “UNITS
SELECTED” and bottom
line reads “ALT / IAS”.
4. Press the PRGM key. Top line reads “UNITS
SELECT” and bottom line
reads “ENGLISH”.
5. a. If ENGLISH units are
desired, press the PRGM
key.
(For METRIC units, Go To
Step 6.)
Top line reads “UNITS
SELECT” and bottom line
reads “KNOTS”. Note: the
altitude unit “FEET” is
associated with Knots.
b. If KNOTS unit are
desired, Go To Step 7.
(For MPH units, Go To
Step 5.c.
5. c. If MPH units are
desired, press the  or 
arrow key until “MPH” is
displayed.
Top line reads “UNITS
SELECT” and bottom line
reads “MPH”. Note: the
altitude unit “FEET” is
associated with MPH.
5.d. Go To Step 7.
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6. If METRIC units are
desired, press the ▲or ▼
arrow key
Top line reads “UNITS
SELECT” and bottom line
reads “METRIC”. Units are
set to METERS and km/h.
7. Press the PRGM key. Top line reads
“PROGRAM MODE” and
bottom line reads “UNITS
SELECT”.
8. Press the ◄key. Manometer returns to
Measure Mode displaying
Altitude.
1. Altitude is the default measurement when ALT /IAS Mode is active.
2. If ALT / IAS Mode was active upon manual or automatic shut off, ALT / IAS
Mode will be restored upon cycling power and altitude will be displayed.
3. When the M203 is displaying air speed and power is turned off (manually or
automatically), Program Mode is entered, or the Tare key is pressed, the unit will
be returned to altitude display once power is cycled or the unit is returned to
Measure Mode. This is a feature designed to prevent errors in air speed
measurement, necessary because of the tare function employed on barometric
pressure to arrive at air speed measurements. Barometric pressure fluctuates with
changes in weather conditions. Reverting to altitude measurement upon powering
down, entering Program Mode or pressing the Tare button forces a new tare value
to be taken prior to each air speed measurement session.
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Damp Rate Select
Adjustable exponential type damping is available to steady the display when
measuring pulsating pressures. The M203 has a range of damping rates; 0.1, 0.2,
0.5, 1, 2, 5, 10, or 25 seconds. Damping is done by averaging new data from the
pressure sensor against previously collected data. The microprocessor collects
data from the sensor every 0.1 seconds. The display updates every 0.5 seconds,
showing the current 0.1 second pressure reading. When set at 25 seconds, the
display updates every 0.5 seconds with the average of the previous 25 seconds
readings. Therefore, it takes up to 25 seconds from the time pressure is applied
until the manometer displays the full scale applied pressure. Min/Max display
updates every 0.1 seconds.
To set the damp rate:
Keystroke Display
1. Enter Program Mode by
pressing the PRGM key.
Top line reads “PROGRAM
MODE”. Bottom line reads
“UNITS SELECT”.
2. Press the ▲key. Bottom line reads “DAMP
RATE SELECT”.
3. Press the PRGM key. Top line reads “DAMP RATE
SELECT”. Bottom line shows
current value.
4. Press the ▲or ▼keys
until the desired damp rate is
displayed on the bottom line
Bottom line shows damp rate
settings in seconds.
5. Press the PRGM key. Top line reads “PROGRAM
MODE”. Bottom line reads
“UNITS SELECT”.
6. Press the ▼key. Bottom line reads “EXIT
7. Press the PRGM key. Returns to Measure Mode.
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User Info Select (Accuracy, SW version, Mfr date, SN)
The User Info Select registers are designed to provide the user with information on
the hardware and software in the manometer. This register provides read only
information on the sensor’s accuracy, software version, date of manufacture and
serial number. It also allows the user to edit the Auto Shut-Off, Lockout and Start-
Up Header Name features.
To access the User Info Select registers, follow the steps below. To configure a
User Info Select register, follow the steps shown on the following page.
Keystroke Display
1. From the Measure Mode
press the PRGM key.
Top line reads “PROGRAM
MODE” and bottom line
reads “UNITS SELECT”.
2. Press the ▲arrow key
twice.
Bottom line changes to
“USER INFO SELECT”.
3. Press the PRGM key. Bottom line shows
accuracy
4. Press the ▲arrow key. Software version no.
shown.
5. Press the ▲arrow key Manufacture date shown.
6. Press the ▲arrow key.
See instructions to set
AUTO SHUT-OFF later in
this manual.
Top line reads “AUTO
SHUT OFF” and bottom
line reads “ENTER TO
SELECT”.
7. Press the ▲arrow key. Bottom Line shows Serial
No.
8. Press the ▲arrow key.
See instructions for using
LOCKOUT later in this
manual.
Top line reads “LOCKOUT
CODE” and bottom line
reads “ENTER TO
SELECT”.
9. Press the ◄arrow key.
See instructions for editing
the Header later in this
manual.
Top line reads “HEADER
NAME” and bottom line
reads “MERIAM”. The
cursor flashes at bottom
left.
10. Press the ◄arrow key
to go back to “USER INFO
SELECT” screen.
Top line reads “PROGRAM
MODE” and bottom line
reads “USER INFO
SELECT”.
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Auto Shut-Off
Enabling the Auto Shut-Off feature allows the manometer to turn itself off after a
user selected period of keypad inactivity. Selectable options include DISABLED,
10 Minutes (which is the factory shipped default), 20 Minutes, 30 Minutes, 45
Minutes and 60 Minutes. Disabling this feature limits the manometer to being
turned off by using the ON/OFF key only.
To configure auto shut-off follow these steps:
Keystroke Display
1. Follow steps 1-6 in
the user Info Select
table.
Top line reads “AUTO
SHUT-OFF” and
bottom line reads
“ENTER TO SELECT”.
2. press the PRGM
key, then the up or
down arrow keys until
the desired shut-off
time is shown.
Top line reads “AUTO
SHUT-OFF” and
bottom line toggles to
“DISABLED”, “10”,
“20”, “30”, “45” and
“60” minutes .
3. Press the PRGM
key.
Desired Auto Shut-Off
time is selected, top
line reads
“AUTO SHUT-OFF”
and bottom line reads
“ENTER TO SELECT”.
4. Press the left arrow
key three times.
Returns to Measure
Mode.
The “Auto Shut-Off” timer is suspended during Data Logging and Leak Test
sessions to prevent accidental loss of information. Auto Shut-Off is re-instated
after completion of Data-Logging or Leak Test sessions.
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Lockout Select
Enabling the Lockout feature prevents unauthorized users from making changes to
the configuration of the manometer. To enter the Program Mode, the user must
first enter the “password” (two-digit Lockout Code) within approximately 40
seconds when prompted. Failure to enter the correct two digit code within
approximately 40 seconds will return the unit to Measure Mode. Any two-digit
numeric code can be programmed. The factory Lockout Code of 00 (which is the
default as shipped from the factory) disables the Lockout.
To set the Lockout Code follow these steps:
Keystroke Display
1. From the Measure Mode
press the PRGM key. If the
Lockout is set, enter the
correct “password” when
prompted.
Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
2. Press the up arrow key
twice.
Bottom line reads “USER
INFO SELECT”.
3. Press the right arrow key
then the up arrow key four
times.
Top line reads “LOCKOUT
CODE” and bottom line reads
“ENTER TO SELECT”.
4. Press the right arrow key,
then press the up arrow keys
to change the first digit. Press
the right arrow key to proceed.
Bottom line shows the old
Lockout Code. The cursor
flashes at the first position
while the value is changed,
the cursor moves to the right
position once the right arrow
key is pressed.
5. Press the right arrow key
when the desired code is set.
Lockout is activated.
Top line reads “LOCKOUT
CODE” and bottom line reads
“ENTER TO SELECT”.
6. Press the left arrow key
twice
Returns to Measure Mode.
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Header Name
Follow the steps below to edit the Header Name.
Keystroke Display
1. From the Measure Mode
press the PRGM key.
Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
2. Press the up arrow key
twice.
Bottom line changes to
“USER INFO SELECT”.
3. Press the PRGM key. Bottom line shows serial
number.
4. Press the up arrow key five
times.
Top line reads “HEADER
NAME” and bottom line reads
“MERIAM”. The cursor flashes
at bottom left.
5. If header is correct press
backspace key. If editing is
desired proceed to Step 7.
Top line reads “PROGRAM
MODE” and bottom line reads
“USER INFO SELECT”.
6. Press the left arrow key. Returns to Measure Mode
7. Press the up or down arrow
keys to set the correct alpha-
numeric value,
Displays a number between 0
and 9, a letter from A to Z, / or
a blank space.
8. Press the right arrow key to
accept entry,
Cursor advances one space to
right.
9. Repeat steps 8 and 9 until
the desired Header is shown.
10. If an error is made press
the back arrow key until the
cursor is over the incorrect
value. Follow Step 8 to correct.
Press the right arrow key to
advance the cursor without
changing the values.
11. When the Header is
complete press the PRGM key
until header accepted.
Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
12. Press the left arrow key. Returns to Measure Mode.
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Contrast Select
The Contrast Select register allows the user to adjust the character contrast of the
LCD display to provide the best visibility for the ambient light conditions.
To adjust the contrast, follow these steps:
Keystroke Display
1. From the Measure Mode
press the PRGM key.
Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
2. Press the ▲key three times. Bottom line reads
“CONTRAST SELECT”.
3. Press the PRGM key, Top line reads “CONTRAST
SELECT”. Bottom line shows a
numerical value.
4. Press the ▲or ▼keys to
increase or decrease the
contrast value. A low number
gives maximum contrast and a
high number gives minimum
contrast.
LCD lightens or darkens
depending on the value set.
5. Press the PRGM key. Top line reads “PROGRAM
MODE” and bottom line reads
“UNITS SELECT”.
6. Press ◄key. Returns to Measure Mode.
If an error is made during the contrast adjustment, pressing the ◄key returns the
display to the previous contrast setting
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