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SafeCheck 200
O2/LEL Gas Monitor
Operator's Manual
Note: Due to the new ATEX Directive in Europe, all
references in this document to "Ex" or "EEx" for intrinsic
safety approvals should be disregarded effective 7/1/03
within the member countries of the European Union (EU). At
this time, this product is not approved in accordance with the
new ATEX Directive and is not sold for use in hazardous
atmospheres or explosive zones by customers within the
EU. Outside of the EU, all references to intrinsic safety
continue without change.
Thank you for choosing Quest Technologies to meet your personal gas monitoring needs. The SafeCheck 200 is a non-datalogging, easy to operate, rugged
personal gas monitor that will measure and alarm for hazardous levels of oxygen
and combustible gases. It is our goal to make your decision to buy Quest
products the right one, and to provide support for any questions or concerns that
might arise.
The purpose of this manual is to provide the user with the necessary information
to operate the SafeCheck 200. The entire manual should be read to fully
understand the many features this instrument offers.
This manual is not all inclusive and cannot cover all unique situations. In addition, no warranties are contained in this manual except as described under the
warranty policy section.
Copyright 1997 Revision A
P/N 054-482
510 S. Worthington St. • Oconomowoc, WI 53066 USA • 800-245-0779 • Fax: 414-567-4047
http://quest-technologies.com
Printed in U S A
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Table of Contents
OPERATIONAL FLOW DIAGRAMS .........................................................1
1. INTRODUCTION...................................................................................4
2. GENERAL OVERVIEW........................................................................5
2.1 Unit Overview ..................................................................................5
2.2 The Keys .........................................................................................6
2.3 Backlight .........................................................................................7
2.4 Alarm and Level Definition..............................................................7
2.4.1 Oxygen Alarm Levels ............................................................7
2.4.2 Combustible Gas Alarm Levels .............................................7
3. OPERATION .........................................................................................9
3.1 Turning the Unit ON .......................................................................9
3.2 Turning the Unit OFF......................................................................9
3.3 User Modes .....................................................................................9
3.3.1 Pass/Fail ...............................................................................10
3.3.2 Basic Mode ..........................................................................10
3.4 Main Menu ..................................................................................10
3.4.1 Run ......................................................................................11
3.4.2 Zero......................................................................................12
3.4.3 Setup ....................................................................................13
3.4.4 Calibration............................................................................15
4. Quest Sensor INFORMATION .............................................................20
4.1 Changing or Installing the Sensors .................................................20
5. BATTERY INFORMATION.................................................................21
5.1 Replacing or Installing the Batteries...............................................21
5.2 Low Battery Warnings....................................................................22
5.3 Recharging NiCAD & NiMH Battery Packs .................................22
5.4 Servicing Alkaline Battery Packs ..................................................23
5.5 Unit Storage With & Without Batteries ..........................................24
6. FACTORS AFFECTING RESPONSE.................................................25
6.1 Combustible Gas.............................................................................25
6.1.1 Rich Atmospheres................................................................25
6.1.2 Oxygen Dependence .............................................................25
6.1.3 Pocketing .............................................................................25
6.1.4 Combustible (% LEL) Relative Sensitivity ..........................26
6.2 Oxygen .......................................................................................26
Table of Contents
7. GAS SPECIFIC DATA ..........................................................................27
8. SPECIFICATIONS.................................................................................28
9. SafeCheck 200 ACCESSORIES ............................................................29
9.1 Replacement Quest Sensors............................................................29
9.2 Accessories ....................................................................................29
9.3 Calibration Kit ................................................................................30
9.4 Regulators ......................................................................................30
9.5 103 Liter Steel Cylinder Calibration Gases ...................................30
10. MultiCharger II ......................................................................................31
11. QTP-2000 SAMPLE-DRAW PUMP .....................................................32
QUEST SERVICE POLICY.........................................................................33
QUEST WARRANTY POLICY...................................................................34
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Operational Flow Diagrams
Operational Flow Diagrams
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Operational Flow Diagrams
Introduction
1. INTRODUCTION
The SafeCheck 200 is a compact, personally worn, two gas monitor that can
simultaneously measure oxygen and combustible gas. Sturdy, lightweight, and
easy to operate, this unit is ideal for industrial use.
Warning: The SafeCheck 200 is intended to measure gases that are potentially dangerous to human health. To help ensure worker safety through the
proper use of your unit, it is important that you not only read but also
understand the contents of this manual. Please familiarize yourself with the
unit before using it in a potentially hazardous situation.
Caution: Underwriters Laboratories, Inc. has assessed only the combustible
gas portion of this instrument for performance.
Note
: When used with alkaline batteries in Canada tested per CSA
(Canadian Standards Association) Standard C22 No. 152,
Combustible Gas Detection Instruments are to be used in Canada
only with the following "C" size alkaline batteries:
Eveready: E93
Duracell: MN1400
Rayovac: 814
Note
Rayovac: No.814LR14
Radio Shack: 23-551
: When used with alkaline batteries in Europe can only be used with:
Varta: No. 4041 LR14.C
Duracell: MN1400LR14
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General Overview
2.1 Unit Overview
General Overview
2.2 The Keys:
In order to make the operation of the SafeCheck 200 as simple as possible,
you only need to use three keys to perform all of the necessary operations.
This key is found on top of your unit above the display screen. You will use it to
▼ ▲ These keys are located above the belt clip. You will need to use the
arrow keys to change the unit's modes, and during the ZERO, SETUP, and CAL
operations. You generally use the ▲ arrow to return to the previous screen and
to adjust numeric values. You generally use the ▼ arrow to scroll through and
highlight menu items, and to select and adjust numeric values.
turn the unit on, to turn the unit off, and to select your desired menu
choices when they are highlighted.
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General Overview
2.3 Backlight:
The unit features a backlight which illuminates the screen for 10 seconds
each time a key is pressed. Refer to Section 3.4.3 Setup under Display
Options on page 14 to enable/disable the backlight illumination feature.
The backlight also illuminates for 10 seconds any time the unit goes into
alarm.
2.4 Alarm and Level Definition:
All of the following levels and alarm levels are based on the measurement
of one sample per second. Refer to Section 3.6.3 Setup under Alarms Set
on page 13 to change any of the alarm activation levels.
2.4.1 Oxygen Alarms and Levels:
Both oxygen deficient atmospheres and oxygen rich atmospheres present
gravely hazardous work conditions.
• Low: The Low alarm level for oxygen is any level less than 19.5%.
Oxygen deficiency is the leading cause of worker fatality during confined
space entry, therefore the importance of monitoring the oxygen level
cannot be overstated.
• High: The High alarm level for oxygen is any level greater than 23.5%.
Oxygen rich atmospheres can lower the combustible range of some gases
and can cause them to burn violently.
2.4.2 Combustible Gas Alarms and Levels:
Combustible gas levels can be measured as a percent of the LEL or as a
percent by volume of CH
Display Options on page 14 to change the way that combustible gas levels
are measured.
• LEL: LEL stands for Lower Explosive Limit. An atmosphere which
contains less than the LEL, the value of which varies among the combustibles is referred to as a lean atmosphere. An atmosphere which
exceeds the UEL, or Upper Explosive Limit, the value of which also varies
among the combustibles, is referred to as a rich atmosphere. The range
between the LEL and the UEL is the combustible (explosive) range.
(methane). Refer to Section 3.4.3 Setup under
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General Overview
The default alarm level is set to 10% of the LEL. When this level is
reached or exceeded, the unit goes into alarm. If the measured level
exceeds 98% of the LEL, the alarm automatically latches on and the unit
will remain in alarm until the unit is taken out of the RUN mode. When
this occurs, a high probability exists that the gas concentration is above the
LEL, in the combustible range, and overloading the LEL sensor.
• CH
: This is a mode where the unit is set up to measure a specific com-
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bustible gas, methane (CH
than a percent LEL concentration. This is just a different way of reporting
the concentration of one specific gas (CH
ume, it is also at 100% of it's LEL point.
The default alarm level is set to 0.5% by volume CH
reached or exceeded, the unit goes into alarm. If the measured level
exceeds 4.9% of CH
remain in alarm until the unit is taken out of the RUN mode. When this
occurs, a high probability exists that the gas concentration is above 5.0%
by volume, in the combustible range, and overloading the combustible gas
sensor.
ALTHOUGH A RICH ATMOSPHERE MAY NOT PRESENT
IMMINENT DANGER OF IGNITING AT THE TIME OF CURRENT
MEASUREMENT, ANY DILUTION OF THIS RICH ATMOSPHERE
COULD BRING THE CONCENTRATION DOWN INTO THE
COMBUSTIBLE RANGE.
) in a percent by volume concentration rather
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). When CH4 is at 5.0% by vol-
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. When this level is
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, the alarm automatically latches on and the unit will
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