TPI 721 User manual

721
Combustible Gas Leak
Detector Instruction Manual
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TABLE OF CONTENTS
A. INTRODUCTION
1. Congratulations ..........................3
2. Product Description....................3
B. SAFETY CONSIDERATIONS ..............4
C. TECHNICAL DATA
1. Features and Benefits..................5
2. Product Applications ..................5
3. Specifications..............................6
D. MEASUREMENT TECHNIQUES
1. Controls and Functions ..............7
2. Step by Step Procedures: ..........9
E. ADDITIONAL FEATURES..................12
F. TROUBLE SHOOTING GUIDE ..........15
H. MAINTENANCE ................................15
I. ACCESSORIES ................................15
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A. INTRODUCTION
1. Congratulations!!
Thank you for purchasing TPI products. The 721 is easy
to use and is built to last. It is backed by a 3 year limit-
ed warranty. Please remember to complete and return
your product warranty registration card.
2. Product Description
The ergonomically designed 721 is a hand-held, com-
bustible gas leak detector. It is capable of finding com-
bustible gas leaks in pipes, fittings, regulators, etc.
Additional features include the capability to display
%LEL, leak level in ppm, and user adjustable alarm
point.
The 721 comes complete with the following accessories:
Carrying Pouch (A780)
Instruction Manual
Battery & Sensor (Installed & Calibrated)
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B. SAFETY CONSIDERATIONS
WARNING: Please follow manufacturers test
procedures whenever possible. Do not place the
sensor cage located on the end of the gooseneck on
hot or in hot locations.
GENERAL GUIDELINES
ALWAYS
• Turn your detector on in a “clean air” environment away
from the test location.
•Inspect the sensor cage to ensure it is securely attached.
NEVER
•Place the detector or sensor cage in or on a hot item.
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C. TECHNICAL DATA
1. Features and Benefits
Auto Zero Automatically sets the sensor to
zero at start up.
%LEL Displays the percentage lower explosive
limit (LEL)
PPM Displays the amount of leakage in
parts per million (ppm)
Mute Mutes the speaker and earphone alarm
Zero Manually sets the sensor to zero
Adjustable Alarm point can be set as required
Alarm
Visual Alarm LED’s located on the front and
Alarm in the sensor cage tip
Auto Off When enabled, the 721 turns off after
approximately 20 minutes to saves battery
life. Can be disabled.
2. Product Applications
Perform the following tests and/or measurements with the 721
leak detector:
• Locate combustible gas leaks in joints and fittings.
• Determine Lower Explosive Limit percentage.
• Determine the combustible gas leak level in ppm (parts per
million).
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3. Specifications
Leak Detection Sensitivity (methane): 10ppm
Gases Detected (partial listing): Acetone, Acetylene, Alcohol,
Ammonia, Benzene, Butane, Ethanol, Ethylene Oxide, Gasoline,
Hexane, Hydrogen, Methane, Naphtha, Natural Gas, Paint Thinners,
Propane, Solvents
Display Type: Dual display with backlight
Display Modes: Real (ppm), Leak Level (stepped ppm), %LEL
Ranges: Real ppm: 0 to 9999ppm
Stepped ppm: 0, 500, 1000, 3000, 5000, 9999ppm
%LEL: 0 to 19.9%
Accuracy: +/-10%
Audible Leak Indication: Adjustable tic rate via side thumb wheel
Alarm Indication: Visual and audible (User adjustable alarm level)
Sensor Test and Zero: Automatic at start up
Goose Neck: 16” long with visual alarm indicator in sensor housing
Operating Temperature: 32 to 122 (0 to 50)
Gooseneck Length: 16 inches
Battery Type: “C” size Alkaline (2)
Size: 9.4” x 2.9” x 2.2” (240mm x 74mm x 55mm)
Weight: 1 lb (454g)
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D. MEASUREMENT TECHNIQUES
1. Controls and Functions:
Push Buttons
Short Press: Turns the 721 on.
Long Press (3 seconds): Turns
the 721 off.
Short Press: Silences the alarm.
Long Press (3 seconds): Activates
Menu Mode.
Short Press: Activates sensor
zero.
Long Press (3 seconds): Turns
the backlight on and off.
Thumb Controls speed of tick rate
Wheel
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D. MEASUREMENT TECHNIQUES
1. Controls and Functions (continued):
Instrument Layout
Keypad
Gooseneck
Display
Sensor cage containing
the sensor and visual
alarm indicator
Speaker
Alarm LED
On Indicator
Tick adjust wheel
Earphone
Jack
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D. MEASUREMENT TECHNIQUES
2. Step by Step Procedures:
WARNING!
Turn the 721 in a “clean air” environment away from the
test area. Failure to do so may cause the 721 to display
sensor error and turn off.
Measurement Procedure:
1. Turn the 721 on by pressing the key. The 721 will begin
a 30 second countdown and “wait” will display. During this
countdown the sensor is being self tested and set to zero.
2. After the countdown is complete the 721 will display “0” and a
tic rate will begin.
3. At this point the display mode can be selected. Once the dis-
play mode is selected the 721 will turn on in the same mode
each time unless changed. If the display mode does not need
to be changed, proceed to step 8.
4. To change the display mode press and hold the key for
approximately 3 seconds to enter menu mode. The following
will be displayed:
5. Press the key to proceed to the display mode screen.
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Step by Step Procedures (continued):
6. Depending on the last display mode selected one of the
following displays will be seen. The display modes can be
changed by using the key to cycle between them.
“REAL” mode will display leak levels in ppm (parts per million)
“LEL %” will display leak levels in %LEL (Lower Explosive Limit)
“0ppm ud (ud=under)” will display leaks in steps. The steps are
0ppm, ud 500ppm, ud 1000ppm, ud 3000ppm, ud 5000ppm, ud
9999ppm
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Step by Step Procedures (continued):
7. Once the desired display mode is selected, press the key
and the following display will be seen:
8. Press the key again to exit menu mode and return to nor-
mal operation.
9. Turn the thumbwheel on the side and set a consistent tic rate. If
necessary the key can be used to zero the display. Enter
the area and begin testing. As a leak is found the tic rate will
increase and depending on the display mode selected, the con-
centration will be displayed on the LCD in ppm, %LEL, or
stepped ppm.
10. To locate the source of a leak, use the thumbwheel to nullify the
increase in tic rate and move along the pipe, fitting, etc. being
tested.
11. Continue to nulify any increases in tic rate and move along the
item being tested until the leak source is located.
12. If the leak concentration is above the alarm level the alarm will
sound and LED’s located in the front panel and sensor cage will
flash.
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E. Additional Features:
Alarm Level Adjustment
The alarm level can be adjusted by performing the following steps:
1. After the 721 has been turned on and has gone through the
warm up period, press and hold the key for approximately
3 seconds to enter menu mode. The following will be displayed:
2. Press the key to proceed to the display mode screen.
3. Press the key to proceed to the alarm adjustment screen.
The following will be displayed.
4. Press the key to increase the alarm level or the key
to decrease the alarm level. The alarm can be adjusted from
100ppm to 5000ppm in increments of 100ppm. Press the
key when finished.
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Additional Features (continued):
Auto Power Off
The auto power off feature can be enabled or disabled as required:
1. After the 721 has been turned on and has gone through the
warm up period, press and hold the key for approximately
3 seconds to enter menu mode. The following will be displayed:
2. Press the key to enable (ys) or disable (no) the auto power
off feature.
3. Press the key to proceed to the display mode screen.
4. Press the key to proceed to the alarm adjustment screen.
5. Press the key to return to normal operation.
Display Backlight
The backlight can be activated at any time as required:
After the 721 has been turned on and has gone through the warm up
period, press and hold the key for approximately 3 seconds to
activate the backlight. The backlight will remain on for approximately
20 seconds.
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Battery indi-
cator
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Additional Features (continued):
Mute Function
When the 721 encounters a gas concentration above the alarm set
point the alarm will begin to sound. Pressing the key will
silence the alarm.
Zero Function
If the 721 fails to auto zero the zero key can be used to zero the dis-
play. Turn the 721 on in a clean air environment, wait for the sensor
test to end, then press the key.
Battery Indicator
The battery indicator is located in the upper right corner of the display
and monitors the condition of the battery:
The battery indicator will show full capacity ( ), half capacity
( ), one quarter capacity ( ), and replace ( ).
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F. Trouble Shooting
Problem Corrective Action
SENS ERR in display Replace sensor
Tick rate inconsistent Replace batteries / sensor
Weak LCD display Replace Batteries
G. Maintenance
Battery Replacement:
Depress the latch on the back housing and slide the cover down.
Replace batteries (2 x “C” alkaline) and reattach the cover.
Sensor Replacement:
Turn the 721 off. Turn the sensor cage counter clockwise and remove
it. Unplug the old sensor and discard. Replace sensor and sensor cap.
Cleaning your 721:
Use a mild detergent and slightly damp cloth to clean the surfaces of
the 721. For factory service please return your 721 to:
TPI / Attn: Service
9615 SW Allen Blvd. Suite 104
Beaverton, OR 97005
H. Accessories
Replacement Sensor: A739
Soft Pouch: A780
Earphone: A710
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