MMC D-2615-11 Manual

MMC INTERNATIONAL CORP
OPERATING AND MAINTENANCE
INSTRUCTIONS
OXYGEN LEVEL SENSOR
GAUGING TAPE
CLOSED AND RESTRICTED APPLICATIONS
MODEL D-2615-11
APPROVED BY:
BASEEFA AS
INTRINSICALLY SAFE FOR USE IN
CLASS I, DIVISION I, GROUPS C & D
HAZARDOUS ENVIRONMENTS
MMC INTERNATIONAL CORP.
60 INIP DRIVE
INWOOD, NEW YORK 11096
OCTOBER 2022 DRAWING FILE NO. A-2615-60

TABLE OF CONTENTS
PAGE NUMBER
I. GENERAL 1
1.1 SPECIFICATIONS 2
1.2 SPECIAL FEATURES 3
II. INTRODUCTION 4
III. THEORY OF OPERATION 5, 6
IV. REQUIRED CONDITIONS AND RECOMMENDED USAGE
4.1 REQUIRED CONDITIONS 7
4.2 RECOMMENDED SAFE USAGE CONDITIONS 7
4.3 FLUID LEVEL (ULLAGE) OF TANK OR OTHER VESSEL 8
V. OPERATION
5.1 FAMILIARIZATION WITH OPERATING CONTROLS & FEATURES
LOCATED ON THE TAPE REEL HUB BEZEL NAMEPLATE 8
5.2 OXYGEN LEVEL MEASUREMENT 8, 9
5.3 OXYGEN SENSOR CELL LIFE 10
VI. CARE AND MAINTENANCE 11
6.1 BATTERY REPLACEMENT
6.2 OXYGEN CELL REPLACEMENT
6.3 GAUGING TAPE REPLACEMENT
CONTINUED ON NEXT PAGE

CONTINUED FROM PREVIOUS PAGE
VII. CALIBRATION PROCEDURE
7.1 METHOD OF CALIBRATION 12
VIII. FAULT FINDING 14, 15
IX. APPENDIX 16
X. LIST OF APPLICABLE DRAWINGS 24

SECTION I
1. GENERAL:
1.1 SPECIFICATIONS:
Oxygen Sensor Measurement Range 0% to 25%
Accuracy over the 1% to 25% Range ±0.2%
Batteries for Intrinsically Safe Operation Duracell #MN1604
Only (supplied)
Battery Life Approximately 1000 Hours
(Depends on night light use)
Battery Drain (Display Night Light off) 1.0 MA (IN AIR)
0.7 ma with <8% Oxygen
Night Light Battery Drain 9.0 ma/use
Storage Temperature -20°C to 40°C
Tape Length (Standard) 50 FT. (15 Meters)
100 FT (30 Meters)
Hazardous Environments Intrinsically Safe
Class I, Division I,
Groups C and D
Approval BASEEFA
Hazardous Environments Certified Intrinsically Safe
BASEEFA/SIRA/CSA I,
Gas Groups C & D
1

1.2 SPECIAL FEATURES:
Simple Automatic Push-Button Calibration in Air
Audible (Horn) and visual (Red LED) indication is provided to designate that the gaseous
mixture within a particular tank or vessel contains an oxygen concentration greater than 8%.
Note: For the intended application area of this device, oxygen content percentages of 8% or less
are considered non-explosive. Also see introductory text within this manual.
Tape Reel Position Lock
Watertight Electronics Housing with Sealed Switches
Stainless Steel Fasteners
Nylon Coated Aluminum Frame, for lightweight portability
Low Battery Indicator
Liquid Crystal Display with Extended Operating Temperature Range
Push Button Display Night Light
Automatic Turn Off (Turn off disabled during measurement)
Oxygen Cells easily replaceable with plug in assembly
Conductive Tape Surface to drain off any static charge
Grounding Lug and Cable supplied
Intrinsically Safe Equipment (BASEEFA) British Approval Service for Electrical Equipment in
Flammable Atmosphere, recognized member of CENELEC
2

SECTION II
2.0 INTRODUCTION:
2.1 The MMC portable oxygen sensor described herein incorporates extremely accurate
instrumentation to provide measurements of oxygen percentage levels in inert gas
protected vessels containing potentially explosive products. The primary field of
application includes petroleum carrying barges and sea going tankers. Other application
areas such as land-based petroleum storage tanks can also use the extra assurance of
safety afforded by the use of this equipment.
2.2 The equipment incorporates the following novel and advantageous features:
2.2.1 Extremely low battery drain (less than 1 milli-ampere) resulting in battery life of
over 1,000 hours.
2.2.2 Automatic power turn-off in air, with turn-off disabled during measurement use in
gaseous environments containing less than 18% oxygen.
2.2.3 Oxygen cell plugs in for simple replacement. 1-year minimum lifetime.
2.2.4 Simple push button calibration with no other operator adjustment required even
when replacing oxygen cells.
WARNING!
This equipment is solely intended for use in determining the percent by volume of
the oxygen that may be present in a protective blanket of inert gas. It is not claimed,
or intended for use in closed or confined spaces, or any other condition where
human safety is of concern.
2.3 The MMC system uses a sensor suspended at the end of a fluoropolymer covered gauging
tape, wound on a reel assembly. The plastic covered steel gauging tape contains two
isolated side conductors to carry the signal and ground from the electronic circuit within
the sensor barrel to conditioning electronics in the reel hub. The surface of the tape has
been treated to make it sufficiently conductive to prevent the build-up of static charges.
Percent oxygen indication is provided by a large digital liquid crystal display (LCD)
located on reel hub assembly.
2.4 In addition to the LCD display described above, which provides accurate reading of
percent of oxygen, the MMC tape also incorporates a pulsating horn and a light emitting
diode (LED), to provide a visual and audible alarm indication of unsafe conditions,
specifically, that oxygen content is above an 8% by volume level.
3

2.5 To minimize the danger of fire and explosive discharge within the tanks on petroleum
carrying vessels, the U.S. Coast Guard has specified that the gaseous environment abo
ethe fluid levels in petroleum cargo tanks be maintained with sufficient inert gas to
reduce oxygen levels below an 8% level.
2.6 A single 9-volt battery contained within the hub assembly powers the oxygen sensor tape
and sensor assembly. Battery drain is extremely low, (approximately 0.75 milli-amperes),
and if the unit is left unattended in the air for more than approximately 5 minutes, power
is automatically shut off. Low battery warning is provided at the upper left corner of the
LCD when the battery voltage has dropped to a level that would, with further operation,
cause erroneous oxygen readings.
4

SECTION III
3.0 THEORY OF OPERATION:
3.1 Drawing S-2615-OCX illustrates the main components of the oxygen sensor. A tape reel crank is
used by the operator to raise and lower the oxygen sensing head assembly, which is attached to
the reel via the tape. In the stored position, the reel lock prevents the sensor and tape from
unreeling due to weight. Before lowering or raising the tape, the reel lock must be unlocked by
turning locking screw counterclockwise.
3.2 The sensor head assembly contains the oxygen cell, resistors, a platinum temperature
compensation sensor, and a cell holder terminated with a plug-in socket connector. A mating
connector plug is part of the gauging tape. This connection is made within a barrel housing
adapter, connecting the sensor, and gauging tape assemblies.
3.3 The sensor assembly is connected electrically to the hub electronics by two wires encased in a
plastic jacket which covers and hermetically seals the wires and a center metallic gauging tape.
The metallic gauging tape is used to connect the sensor barrel housing to hull ground and provide
sensor payout positions. The marking of gauging tape is provided in a single marking system,
English or Metric.
3.4 The electronic circuits in the hub assembly are comprised of LCD display that provide percent
oxygen level readings, a night light switch, alarm horn and associated red LED lamp. The above
parts and ancillary electronics parts are all assembled on a printed circuit board. A 9-volt battery
power source and audio horn are located within the tape reel hub assembly directly below the
printed circuit board of the modular hub cover assembly. The night switch in conjunction with the
power on-off switch may be used to give instant push button calibration of the system in air (See
section 7.0).
3.5 When the oxygen sensor is powered in a normal ambient environment, the reading of the digital
will show an oxygen in air content of 20.9% (±0.2%). This is the normally accepted value of
atmospheric air at sea level. Ordinary air is therefore used in this system as a standard for
calibration of the sensor. However, calibration is only necessary when replacing the oxygen cell
contained within the sensor housing assembly, or when the battery is replaced. To perform a
calibration, it is only necessary for the operator to first hold down the night light push button; and
then, without releasing the night light push button, to press the power on-off button. The display
will at first show a low value, but then change quickly to the correct percent air oxygen reading,
namely 20.9% (±0.2%). Both are then released.
3.6 It is important not to attempt calibration of the unit when the sensor is in a petroleum tank, or in
other than a normal air environment. It is also desirable to perform the calibration at room
temperature (70 to 80 degrees F). The latter condition is not a requirement, but will, in general,
result in greater accuracy. Although the sensor is temperature compensated to provide minimum
error for temperature change, sudden large temperature shifts may cause errors of approximately
0.3% unless the sensor is given time to recover and the temperature to stabilize.
3.7 In operation and as the oxygen sensor descends into a lower oxygen gaseous environment, such
as that contained in a petroleum tank with inert gas, the output current from the sensor decreases
causing the hub amplifier to linearly experience a lower input voltage. Digital output to the
display is then also decreased. This voltage after conditioning will be proportionally displayed at
the correct lower oxygen percent level encountered.
5

3.8 Normally, and if left unattended in air after power is applied, timing circuits within the hub
assembly will permit the system to remain on for approximately 5 minutes and then will
automatically turn the power off. However, when lowered into a gaseous environment containing
less than 18% oxygen, an internal voltage comparator senses this condition and prevents the unit
from turning off until it is once again exposed to a normal air environment, Thereafter,
approximated one minute of additional on power is permitted before the unity automatically turns
off during a measurement cycle.
3.9 The alarm circuit within the hub consists of 18% oxygen level comparator described above, an
8% comparator, a red lamp (LED) and horn as visual and audible alarm indicators, with other
ancillary electronic circuits.
3.10 When the sensor is powered in a normal air environment, the oxygen level is well above the 8%
level and the red LED lamp on the faceplate will flash slowly. The horn is silent. If the sensor is
now lowered into a tank which contains an oxygen level below 18% but above 8%, the horn will
now emit a pulsating audible tone and the red lamp will then begin to flash at a rapid rate. Below
8% the horn will be silent, and the red LED will extinguish.
To Summarize:
Above 18% Lamp slowly Flashes, Horn Silent (Power on indicator)
From 8% to 18% Lamp Rapidly Flashes, Horn Sounds
Below 8% Lamp off, Horn Silent
3.11 As can be seen from the above table, during an above acceptable level of oxygen contents, both
red LED and horn are off. In addition, the action of the red LED is explained as follows:
3.12 The red LED lamp served two purposes.
3.13 The first purpose is to act as a simple power on indicator in normal air during day and nighttime
use. This feature is important at night since an operator may not be aware that automatic shut-off
has occurred and attempt a gauging procedure.
3.14 The second purpose is to provide an additional indication that an unsafe in-tank oxygen level
exists. In the event that an operator has difficulty in hearing the alarm horn, the rapidly flashing
red LED can be clearly seen.
6

SECTION IV
4.0 REQUIRED CONDITIONS AND RECOMMENDATIONS FOR SAFE USAGE:
The attention of the user of this apparatus is drawn to the possible hazards of oxygen sensing
within flammable environments normally found above confined petroleum liquids, which are
known to be generators of static electricity, and which are not covered with an inert gas blanket.
The following is a general guidance to safe usage, drawn from the advice and experience of
various industry sources.
The specific safety standards or directives of your company are to be strictly adhered to, with the
general guidance given here being regarded as only a supplement to existing and established
operating safety procedures.
4.1 REQUIRED CONDITIONS:
The oxygen sensor frame and reel assembly are to be earthed (grounded) to the liquid
tank containment vessel or tank, before and during introduction of the gauging equipment
into the vessel. The earthing conductor must not be disconnected until the equipment is
completely withdrawn from the vessel being gauged. A coiled grounding cable with a
heavy alligator spring clamp is provided with the equipment. Proper grounding of this
cable is the responsibility of the user.
4.2 RECOMMENDED SAFE USAGE CONDITIONS:
4.2.1 The apparatus’ sensor should preferable be entered into a tank or vessel within an
earthed sounding tube or pipe where such devices are provided and are normally
used for temperature and/or other fluid measurements.
4.2.2 For sea going vessels where gauging is normally accomplished through standard
cargo tank ullaging hatch ports or other approved means, the following
precautions should be observed.
4.2.3 Sensor entry into tanks or vessels immediately following a tank filling or loading
operation of known static accumulator type petroleum products or other
flammable liquids, should not be attempted until, at least a period of 30 minutes
has elapsed since the cessation of filling.
4.2.4 Clean oil distillates are, in general, known to be accumulators of static electricity
due to their low conductivity (i.e., less than 1000 picosiemens/meter) and
therefore may require relaxation periods greater than 30 minutes before gauging is
attempted. The foregoing does not consider use of anti-static additives to clean
oils, as generally easing the need for proper precaution, unless actual and specific
product testing has shown the product to have conductivity levels which eliminate
the danger of static charging.
4.2.5 The presence of an inert gas blanket above products of this type may generally
relax the above precautions. However, such determination is to be made by
qualified authorities.
7

SECTION V
4.3 FLUID LEVEL (ULLAGE) OF TANK OR OTHER VESSEL WHICH IS TO BE
GAUGED FOR OXYGEN PERCENT LEVEL:
4.3.1 Before entering the free space above a liquid level, the level of the fluid contained within
the tank or vessel should be known. If the location of fluid level is not known, it should
be determined by suitable and reliable means.
4.3.2 With the fluid level known, the oxygen sensor can be entered into the tank and unreeled
to the mid-point position of free space above and between the liquid level and tank top
CAUTION!
Under no circumstances should the oxygen sensor be immersed into fluid.
Immersion into fluid will disable use of the sensor unity until a thorough cleaning
and drying of the sensor cell is performed. However, this procedure may not always
return the sensor to an undamaged state, and sensor replacement should be
performed.
8

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1

SECTION VI
6.0 CARE AND MAINTENANCE:
Proper care and maintenance should be practiced to maintain long, trouble free and accurate
service and to maximize battery life, as follows:
6.0.1 When not in use, make sure power is off as evidenced by display being extinguished.
6.0.2 Store sensor head assembly in the fully wound position and store in a dry location. Do
not allow the instrument to remain for long periods in direct sunlight, or store in
temperature above 125°F, or in temperature below freezing. Such temperatures may
damage the liquid crystal display.
6.0.3 Make sure before lowering the sensor into a tank, that the tank product level is known, so
that the sensor is not immersed int the product. Before lowering the oxygen sensor,
always obtain an accurate ullage reading by using an MMC ullaging tape or similar
device. (See Section 5.0).
6.0.4 Each time the sensor is raised from the tank, place the spring-loaded tape wiper switch in
the “ON” position, to clean gauging tape of product smears.
6.0.5 Lubricate drum shaft and bearing with light machine oil to keep it free turning.
6.0.6 Never permit tape and sensor head to unwind freely (control speed of descent by use of a
restraining force on tape reel crank).
6.1 BATTERY REPLACEMENT (In Safe Area Only!)
The battery should be replaced whenever the “LO BAT” symbol appears at the upper left corner
of the display. If the sensor is used to obtain oxygen level readings when the battery is low, large
errors may result.
Before replacing battery, turn power off by depressing “ON/OFF” switch. Always replace
battery in a gas free atmosphere. Remove the six machine screws from the outside retaining ring
on the hub cover. Lift the bezel faceplate cover with its attached P.C. Board. The battery is
retained within the reel by a spring clip battery holder under the modular faceplate assembly.
Remove the battery from the battery cap connector. Replace the battery with a fresh battery of
the type listed on the approval label only. Make sure the battery is inserted with correct polarity.
Positive (+) side of battery to positive (red) side of battery cap. Take care to align the viton cover
casket, and machine screw fasteners when re-assembling to tape reel hub.
IMPORTANT!
After battery is replaced, it is necessary to re-calibrate the oxygen sensor using the simple push
button procedure given in Section 7.0.
13

6.2 OXYGEN CELL REPLACEMENT
:
6.2.1 The oxygen cell, located within the sensor barrel, has a life expectancy of at least one
year. The cell is similar to a battery except unlike a battery, it produces a current which is
directly proportional to the level of oxygen it senses in a gaseous environment. In normal
air, the current generated by a live cell is approximately 0.8 milli-amperes, which
produces a conditioned reading on the display of 20.9% ±0.2. This current output is very
constant in normal air throughout the cell’s life. At end of life the output drops quickly
and reading in the air will suddenly drop below 20.9%. When the push button calibration
procedure given in Section 7.0 can no longer be performed, the cell must be replaced.
6.2.2 To replace the cell, unscrew the retaining cap and screen at the lower extremity of the
sensor barrel housing assembly. The cell housing can not be extracted by holding in a
vertical position. Unplug cell from its mating connector. Replace with fresh cell, making
sure to seat connector and mating plug securely before re-assembly into barrel housing.
Re-insert cell into the barrel, while slightly rotating the cell assembly. Replace screen and
retaining cap. Then follow procedure given for cell calibration in Section 7.0.
6.3 GAUGING TAPE REPLACEMENT
In case of damage, the gauging tape may be replaced by following the procedure below:
6.3.1 Remove the oxygen sensor assembly by unplugging it from the tape end.
6.3.2 Remove storage barrel by loosening cap nuts on the side of the tape wiper housing.
6.3.3 Remove the round vapor seal assembly on the top of the tape wiper housing by backing
off the Allen set screw which holds it in place.
6.3.4 Now place the tape wiper in the off position and remove the tape wiper housing by
unfastening the (4) machine screws in the front of mounting plate. Pull the wiper
assembly out.
6.3.5. Completely unreel the old tape assembly.
6.3.6 Remove the six machine screws from the hub cover and lay it to the side.
6.3.7 Remove the battery from the battery holder and unplug the battery cap.
6.3.8 Note that the end of the metallic tape inside the hub is grounded by a machine screw and
washer. The tefzel tape cover at this point has been trimmed away to permit good ground
contact. Also note that the tape’s outer conductors are spliced to two of the wires that
originated at circuit board. Notice the color of these wires so that when re-assembling, the
correct wire will be connected t the top and bottom tape conductor.
14

6.3.9 Detach the tape at the hub removing the grounding machine screw and unsoldering the
spliced connections between gauging tap and PCB connection wires.
6.3.10 Note on the tape reel which way the tape scale is facing.
6.3.11 Pull the tape away to the hub by reverting hub reel through the tape wiper housing, and
out through the slot in the side of the reel hub.
6.3.12 Attach a new tape to hub by reversing the above procedure making sure that the tape
numerals face in the same direction as the previous tape numerals faced.
6.3.13 Use a silicone rubber sealant to re-seal area around slotted tape entrance to reel hub. Re-
wind tape onto reel, replace round vapor seal assembly, and re-install wiper assembly.
6.3.14 Replace battery, battery cap and hub cover, after allowing silicone sealant at least two
hours curing time.
6.3.15 Re-connect oxygen sensor assembly to tape barrel housing end.
6.3.16 Since the battery is temporarily removed during the tape replacement procedure, re-
calibration is required. Follow method of calibration procedure in Section 7.0.
15

SECTION VII
7.0 CALIBRATION PROCEDURE:
7.0.1 The Oxygen Sensor and associated electronics have been accurately calibrated at factory.
The oxygen cell used, and the electronic circuits are extremely stable and in general
require calibration only when the 9-volt battery or the oxygen cell is replaced.
7.0.2 A simple way to perform push button calibration has been incorporated in the design
which permits the operator to quickly bring the system into calibration using the oxygen
content of normal air (20.9%) ±0.2% as standard.
7.1 METHOD OF CALIBRATION:
Calibration should be performed in a normal air environment and if possible, at room temperature
(68 to 78°F).
7.1.1 Turn power on by depressing the power “ON/OFF” push button. Wait approximately 10
seconds for display to stabilize. Display should read 20.9% ±0.2. If proper reading is
obtained there is no need to calibrate. If an incorrect reading is obtained, look at the upper
left corner of the display. If “LO BAT” appears, indicating a low battery condition,
replace the 9-volt battery contained in the hub following the procedure given in Section
6.
Note: When a 9-volt battery is replaced or temporarily removed, the memory circuits
within the hub may lose their charge and cause the display to produce an
abnormally low reading. If all the charge has leaked off, the reading will be zero.
7.1.2 To perform the simple push button calibration depress the “Display Light” push button
labeled “1” and while holding it in depress the power “ON/OFF” push button labeled “2”.
Now release both. The display will jump to a low-value and quickly climb to a correct
reading of 20.9% ±0.2. The order of button depression must be followed in the order
described.
7.1.3 No further adjustment is required.
Note: If the oxygen cell has reached end of life, calibration will not be possible. A lower
display reading of random value will be obtained each time calibration is
attempted. Cell replacement must be performed to re-establish normal usage. See
sell replacement in this manual.
16

SECTION VIII
8.0 FAULT FINDING
The following section covers only simple faults that may occur. No attempt has been made in
this section to cover highly technical faults.
PROBLEM NO. 1: Unit does not turn on when power “On/Off” switch is depressed.
PROCEDURE &
EXPLANATION: If unit does not turn on at all, check battery voltage using a voltmeter. If
battery voltage is lower than 6.6 volts, the voltage is too low to illuminate
display. Replace battery. (See Section VII Paragraph 7.5). If battery is
okay, check power “On/Off” switch using an OHM meter with the battery
disconnected. Switch is a double pole, single throw (DPST) unit. Both
sections should normally show open circuits. When depressed, ohmmeter
reading should be less than 2 ohms. If switch is not OK, return to factory
or authorized service center for repair.
PROBLEM NO. 2: Unit stays on all the time, even though “On/Off” push-button is depressed.
PROCEDURE &
EXPLANATION: This symptom is usually indicative of a faulty power “On/Off” push-
button switch. Check the switch with an Ohmmeter as explained in
Problem No. 1 above.
PROBLEM NO. 3: When turned on in normal air, unit does not read 20.9 ±0.2, and nothing
happens when the simple push button calibration procedure is followed.
PROCEDURE &
EXPLANATION: If either the power “ON/OFF” switch or the display light switch has a
faulty contact, it will not be possible to perform the calibration. These
switches are both Double Pole Single Throw (DPST) switches, which can
be easily checked with an ohmmeter. Remove the battery when making
ohmmeter checks. Return to factory or authorized service center for repair.
PROBLEM NO. 4: When unit is turned on, in air, unit does not read 20.9±0.2. When simple
push button calibration is attempted several times, the readings are
random, and always too low (less than 20.9). LCD does not indicate low
battery voltage condition.
PROCEDURE &
EXPLANATION: The above symptom indicates that the oxygen sensor within its barrel has
reached end of life and must be replaced. Follow replacement procedures
given under Section 6.0.
17

PROBLEM NO. 5: Same as Problem #4 above, except the simple push button calibration
always results in the same reading, which is incorrect (Too high or too
low), by 0.3% or more.
PROCEDURE &
EXPLANATION: Check upper left corner of display for “LO BAT” indication. If okay, unit
needs factory calibration.
PROBLEM NO. 6: Display reads a value very close to zero (0.00) when unit is turned on in
normal air.
PROCEDURE &
EXPLANATION: 1. If battery has been replaced, the memory circuits have probably
lost their charge and unit must be re-calibrated using the simple
push button procedure given in Section 7.0.
2. If the simple push button calibration results in a reading close to
zero or zero, remove oxygen cell from sensor assembly following
procedure given under Section 6.0. Once removed, examine the
female connector attached to cell housing. Hold the cell housing so
that the “V” notch in the center ring of the connector is up. See
drawing A-2615-17. Connect the positive lead of a digital
voltmeter capable of reading millivolts to pin from the “V” notch.
The reading should be at least 13.5 millivolts or more. If the
reading is less that 12 millivolts, the cell has reached “end of life”
and should be replaced. If reading is above this value and reading
close to zero is obtained on the display, then a break in connection
(open circuit) probably exists in the gauging tape wires or
elsewhere. Use an ohmmeter to measure the continuity of the male
mating plug pins (3, 4, 6) connecting the red, black and white
wires to gauging tape 2 wire conductors and metal scale, back to
the hub electronics connection point.
PROBLEM NO. 7: Alarm circuit (Red LED or horn) does not function properly.
PROCEDURE &
EXPLANATION: 1. Unit requires factory calibration.
2. Horn may be badly corroded.
3. Comparator is not functioning properly.
4. Return to MMC or authorized service center for repair.
18

CAUTION
This equipment is an approved intrinsically safe device. The factory of approved service centers
may only make circuitry repair. Unauthorized repairs will void any guarantee or warranty given
elsewhere in this manual. In addition to the above statement, it is equally, if not more important
to understand that repairs by unqualified persons may endanger the intrinsically safe construction
of this device.
19

APPENDIX
PAGE
NUMBER
A. MMC Warranty Statement 21
B. Oxygen Sensor Gauging Tape Warranty Addendum 22
C. Glossary of Approvals 23
D. BASEEFA Certificate of Conformity Ex93C2037X 25-28
20