Zellweger MINIGAS MK5 User manual

operating instructions
MINIGAS MK5
MULTIPLE DISPLAY 4-IN-1
GAS MONITOR
MAN0585.PM6 Issue 01 - 11/99
2987M5023

MAN0585.P65 Issue 01 - 11/99
2987M5023
2
INTRINSIC SAFETY APPROVAL
Ensure that you read and understand these Operating Instructions BEFORE
operating any part of the Minigas Mk5.
The Minigas Mk5 has been approved as intrinsically safe by authorities
throughout the world. It is important that, as a matter of safety, the conditions
of those approvals are maintained.
The following warning was issued by BASEEFA and appeared in the
EECS News (No. 14) dated April 1991:
“With regard to repairs, the owner of the equipment is responsible for
ensuring that the repairs are carried out in such a way that the explosion
protection measures incorporated in the equipment remain in compliance
with the appropriate standards. Not only should a competent repairer be
used, but also the specification for the repaired equipment should ideally
be obtained from the manufacturer. Unless the repairs are carried out by a
manufacturer who holds an appropriate EECS licence, we (BASEEFA)
can offer no assurance with regard to the quality of the work done.”
The following warning, applicable to intrinsically safe instruments, was
issued by CoGDEM in October 1992:
CoGDEM
THE COUNCIL OF
GAS DETECTION EQUIPMENT MANUFACTURERS
WARNING
This is a certified product. Service, repair or calibration other than by
the manufacturer or a manufacturer's recommended agent may cause
invalidation of certification, warranty, and result in a safety hazard.
CONFORMITY WITH EUROPEAN
DIRECTIVES
Within the European Union, the CE mark is used in to show conformity with
applicable New Approach Directives specifying the health and safety
requirements.These requirements include EMC and ESD standards.
Within the limits of EMC Directive 89/336/EEC, the design of the Minigas
Mk5 has been tested to EN50 082-2: 1995 to ensure that it has adequate
immunity to RFI and ESD encountered in recommended applications.
Similarly, tests have been carried out to EN55 022: 1995 Class B to ensure
that the Minigas Mk5 does not produce electrical interference.

3
MAN0585.P65 Issue 01 - 11/99
2987M5023
WARNINGS AND CAUTIONS
WARNING
The Minigas Mk5 is to be serviced, and the battery charged, only in a safe
area.
Substitution of components may impair the intrinsic safety of the
MinigasMk5.ReplacementpartsmustbeapprovedbyZellwegerAnalytics.
This applies to all parts, including sensors, components and accessories.
CAUTION
The Minigas Mk5 must be serviced only by qualified personnel trained
by Zellweger Analytics or by a Zellweger Analytics appointed agent.
This Reference Manual must be read and fully understood before
servicing the Minigas Mk5.
Note: Failure to observe and abide by the above Warnings and Cautions
may render the intrinsic safety approval void and may remove any
right of claim against Zellweger relating to product liability or
consequential damage to any third party.
CAUTION
The following gases or substances may contaminate the explosive gas
sensor (pellistor) in the Minigas Mk5:
Silicones
Halogens (>100 ppm)
Halogenated hydrocarbons
Phosphorous-containing compounds
Sulphur containing compounds (>100 ppm)
Volatile organometallics
IftheMinigas Mk5 hasbeenexposed to anyofthe above contaminatinggases
or substances, carry out the calibration check described in Chapter 6.

MAN0585.P65 Issue 01 - 11/99
2987M5023
4
CSA AND SAA APPROVAL ADDENDUM:
In addition to the previous Warnings, Cautions, Notes etc. the following
Cautions are applicable to instruments used in USA, Canada and Australia:
CAUTION
Before each day’s usage, sensitivity must be tested on a known
concentration of methane equivalent to 19 to 35% of full-scale
concentration. Accuracy must be within -0 to +5% of actual. Accuracy
may be corrected by recalibration (see Chapter 6).
Anyrapidup-scalereadingfollowedbyadecliningorerraticreadingmayindicate
a gas concentration beyond upper scale limit which may be hazardous.
High off-scale readings may indicate an explosive concentration.
Only the combustible gas detection portion of this instrument has been
assessed for performance.
After a high concentration reading, carry out a recalibration check (see
Chapter 6).
HELP US TO HELP YOU
Every effort has been made to ensure the accuracy in the
contents of our documents, however, Zellweger Analytics
Limited can assume no responsibility for any errors or
omissions in our documents or their consequences.
Zellweger Analytics Limited would greatly appreciate being
informed of any errors or omissions that may be found in the
contents of any of our documents and to this end we include
the following form for you to photocopy, complete and return
to us so that we may take the appropriate action.
CSA AND SAA APPROVAL

5
MAN0585.P65 Issue 01 - 11/99
2987M5023
Marked up copies attached (as appropriate): Yes / No
Please inform me of the outcome of this change: Yes / No
For Marketing Communications, Zellweger Analytics Limited:
Actioned By Date:
Response: Date:
I suggest the following corrections/changes be made to Section ...........
To: Marketing Communications,
Zellweger Analytics Limited,
Hatch Pond House,
4 Stinsford Road,
Nuffield Estate,
POOLE. Dorset.
BH17 0RZ.
United Kingdom.
Tel : [phone]
Fax : [phone]
email : markcom@zellweger-
analytics.co.uk
From :
Address :
Tel :
Fax :
email :
HELP US TO HELP YOU

MAN0585.P65 Issue 01 - 11/99
2987M5023
6

7
MAN0585.P65 Issue 01 - 11/99
2987M5023
CONTENTS
Section Page
1. GENERAL DESCRIPTION 11
1.1 Introduction 11
1.2 Brief description 12
1.3 Accessories provided with the Minigas Mk5 12
1.4 Software options 13
2. USING THE MINIGAS MK5 19
2.1 Introduction 19
2.2 Front panel display format 20
2.3 Preparation for use 21
2.4 Switching on 21
2.4.1 Start-up sequence 21
2.4.2 Displaying the instrument serial number 23
2.4.3 Datalogging warnings 23
2.4.4 If countdown stopwatch alarm is configured 24
2.5 Switching off 26
2.6 Display backlight 26
2.7 Display mode 27
2.7.1 General 27
2.7.2 Display screens 27
2.7.3 If countdown stopwatch alarm is configured 29
2.7.4 Time-of-day display 30
2.8 Zero setting 31
2.8.1 Checking zero readings 31
2.8.2 AutoZero facility 31
2.9 Resetting peak readings 32
2.10 Watchdog signal 33
2.10.1General 33
2.10.2Silent watchdog facility 33

MAN0585.P65 Issue 01 - 11/99
2987M5023
8
2.11 Go/NoGo mode 33
2.12 Standby mode 34
2.13 Autorotate 35
2.14 The datalogging facility 35
2.15 Alarms 36
2.15.1General 36
2.15.2Visual alarms 36
2.15.3Audio alarms 37
2.15.4Alarm cancelling 37
2.15.5 Alarm priority 39
2.16 Instrument warnings and faults 40
2.17 Operational error indication 41
2.18 Low battery indication 41
2.18.1 Low battery indications 41
2.18.2 Battery voltage indication 42
3. USE AND TRANSFERRING DATA AFTER USE 45
3.1 Introduction 45
3.2 Confined space entry 46
3.2.1 Initial area check 46
3.2.2 Confined space entry checks 46
3.2.3 Adsorption of toxic gases 47
3.3 Normal use of the Minigas Mk5 48
3.4 Area monitoring 49
3.5 Storage of the Minigas Mk5 49
3.6 Data transfer after use 50
4. ROUTINE MAINTENANCE 53
4.1 General 53
4.1.1 Preventive maintenance 53
4.1.2 Corrective maintenance 54
4.2 Changing the battery pack 55
CONTENTS

9
MAN0585.P65 Issue 01 - 11/99
2987M5023
4.3 Charging the rechargeable battery 56
4.3.1 General 56
4.3.2 Fast charger 56
4.3.3 Trickle charger 57
4.3.4 Charging the Minigas Mk5 batteries 57
4.4 Changing dry-cell batteries 59
4.5 Sensor grill filter replacement 60
4.6 Service 61
5. FIELD SETTABLE ALARM MODE 63
5.1 Introduction 63
5.1.1 General 63
5.1.2 Field settable alarms 63
5.2 Changing alarm levels 64
5.2.1 General 64
5.2.2 Entering field settable alarm mode 64
5.2.3 Oxygen alarms 65
5.2.4 Explosive alarms 66
5.2.5 Toxic alarms 67
5.2.6 Conclusion 70
5.3 Indication of user configuration 70
6. CALIBRATING THE MINIGAS MK5 71
6.1 Introduction 71
6.1.1 General 71
6.1.2 EasyCal calibration method 71
6.2 Tools and test equipment 72
6.3 Preparation for calibration 73
6.3.1 General 73
6.3.2 Adsorption of the test gas 73
CONTENTS

MAN0585.P65 Issue 01 - 11/99
2987M5023
10
6.3.3 Purging the gas connections 75
6.4 Calibration procedures 75
6.4.1 General 75
6.4.2 Entering Calibration Mode 76
6.4.3 Simultaneous zeroing 76
6.4.4 Span calibration 77
6.4.5 Calibration failure 80
6.4.6 Storage of calibration results 81
6.5 Post calibration 82
6.6 Setting gas bottle concentrations 82
7. SPECIFICATIONS 85
7.1 Minigas Mk5 specification 85
7.2 Battery charger specification 90
7.3 Toxic sensor cross-sensitivity 91
8. OPTIONAL ACCESSORIES AND SPARES 93
APPENDICES
A Glossary of Terms and Abbreviations 97
TABLES
1. Minigas Mk5 alarm signal bleep patterns 38
2. Minigas Mk5 warning codes 40
3. Minigas Mk5 fault codes 43
FIGURES
1. Display screen selection sequence 28
2. Minigas Mk5 fitted into a battery charger 56
3. Minigas Mk5 sensor layout 61
4. Gas calibration kit 74
CONTENTS

11
MAN0585.P65 Issue 01 - 11/99
2987M5023
1. GENERAL DESCRIPTION
1.1 INTRODUCTION
This section describes the standard and optional features of
the Minigas Mk5 instrument.
The Minigas Mk5 is a small, portable gas monitor designed to
be carried or worn without hindering the user. Its purpose is to
monitor the atmosphere continuously for hazardous levels of
four gases simultaneously.
The instrument is usually supplied with four gas sensors - for
detecting oxygen, explosive gases and two toxic gases
(selected from the five currently available toxic-gas sensors).
If required, it can be configured for monitoring only one, two or
three of these gases.
Note: Throughout this manual it is assumed that the
Minigas Mk5 is fully equipped with all four sensors.
References to sensors not fitted in the user’s instrument
should be ignored.
The two toxic-gas channels, referred to as Toxic 1 and Toxic 2,
can be configured only in the following manner:
Toxic 1: Carbon monoxide, or hydrogen sulphide, or
chlorine.
Toxic 2: Carbon monoxide, carbon dioxide, hydrogen
sulphide or sulphur dioxide.

MAN0585.P65 Issue 01 - 11/99
2987M5023
12
1. GENERAL DESCRIPTION
1.2 BRIEF DESCRIPTION
The Minigas Mk5 is a rugged, self-contained instrument with a
die-castzinc metalcase foruse inmining andsurface industries.
It has the option of either a dry-cell or a rechargeable battery
pack, which it is permissible to change in a hazardous area if
necessary.
Concentrationsof gasesin theair aremeasured usingZellweger
Analytics sensors. Audible and visual alarms alert the user to
the danger when hazardous or dangerous conditions are
detected.
Centraltothe operation of theMinigasMk5 is a microprocessor
which provides a multiple-display digital readout of real-time
concentrations of the four gases and their associated peak
readings. The Minigas Mk5 also produces short term (STEL)
and long term (LTEL) indications of toxic gas exposures, an
optional STEL reading for explosive gas exposure, and an
‘elapsed time since switch on’ display.
Data logging facility is available as standard. This enables up
to approximately 40 hours of exposure data to be stored either
as a fixed log where logging stops when the log store is full, or
as a rotating log where logging continues after the store is full
by overwriting the oldest data. Data can then be downloaded
for analysis by means of a special Neotronics transfer unit, an
IBM-compatible personal computer and dedicated software.
1.3 ACCESSORIES PROVIDED WITH THE
MINIGAS MK5
The complete Minigas Mk5 instrument comprises a multi-gas
monitor fitted with a plug-in battery pack, either rechargeable
(NiMH) or dry-cell.

13
MAN0585.P65 Issue 01 - 11/99
2987M5023
The following items are provided as standard accessories with
the instrument:
P085 0002 00 2mm A/F hexagonal wrench (Allen key), for
replacing sensors and for access to the
calibration button.
2987M5021 User Reference Card.
P047 1043 00 Metal belt clip.
P300 0187 00 Chest harness.
1.4 SOFTWARE OPTIONS
The following programmable facilities can be configured into
the Minigas Mk5, either at the time of ordering the instrument
or as a subsequent modification. However, it should be noted
that certain options are incompatible with each other - for
example, the AutoZero and Standby mode options are not
available with Go/NoGo instruments. A Minigas
Questionnaire (part no. 006 0386 01) is available to assist
ZellwegerAnalyticsdistributors and their customers indefining
the Minigas Mk5 configuration (that is, software options, alarm
levels etc) to suit particular user requirements.
Note: Modifying Minigas Mk5 instruments to change or add to
theoptionscanbe carried out only byZellwegerAnalytics,
an Authorised Distributor or a user who has purchased an
option to use Neotronics configuration software.
The # column indicates standard options that are
configured unless requested otherwise. This manual
describes the use of all the standard options.
1. GENERAL DESCRIPTION

MAN0585.P65 Issue 01 - 11/99
2987M5023
14
Option Brief Description
Peak (low) Display of the minimum oxygen measurement
since switch on, or since the last peak reset.
Available for oxygen channel only.
Peak (high) Display of the maximum measurement since
switch-on, or since the last peak reset.
STEL measurement Display of the short term exposure calculation
(not available for oxygen channel).
LTEL measurement Display of the time weighted average
calculation (not available for oxygen or
explosive channels).
Enable Warning Explosive and toxic gas instantaneous first
Alarm Bleep level (high) dual-tone alarms changed to a
single-tone warning bleep (see Section
2.15.3).
Disable Dual Tone As the Enable Warning Alarm Bleep but also
Alarm Bleep with all other gas dual-tone alarms changed
to single-tone (see Section 2.15.3).
Alarm Jump Under alarm conditions, the instrument
immediately displays the appropriate
measurement. Ifmore than one alarm occurs,
it shows the screen with the highest priority
alarm.
Alarm Cancel Allows the alarm signal on the displayed
screen to be cancelled and other screens to
be selected (see Section 2.15.4).
Also allows the alarm to be cancelled after
conditions have reverted to safe.
Cancel All-in-Sight Allows all alarms on the displayed screen to
be cancelled (under conditions where more
than one alarm occurs at same time).
Alarm Silence Only the audio warning is cancelled. The
flashing legends and lights remain as a
continuing reminder of the alarm condition.
#
#
#
#
#
#
#
#
#
1. GENERAL DESCRIPTION

15
MAN0585.P65 Issue 01 - 11/99
2987M5023
Option Brief Description
Disable Latching This option allows alarms to cancel auto-
Alarms matically when conditions return to safe.
Disable Off in Alarm With this option, the Minigas Mk5 cannot be
switched off while in an alarm condition.
Stay-cancelled The selected alarm willnot recuronce Selected
Alarm cancelled (until the instrument is
switched off and on again). For example, if a
low-oxygen alarm is used to indicate that
breathing apparatus must be used, the
Minigas Mk5 can continue to be used to sense
for explosive conditions.
Forced Response When the low battery indication first appears,
to Low Battery it must be acknowledged. This ensures that
the user is fully aware that the battery pack is
becoming exhausted (see Section 2.18).
Battery Voltage Additional Display Mode screen for checking
Indication the battery pack voltage (see Section 2.18.2).
Standby Mode Battery-preserving facility. In particular, saves
power used by the explosive-gas sensor (see
Section 2.12).
Autorotate The display continuously steps through the
available screens, pausing on each for
approximately three seconds (see Section
2.13).
Silent Watchdog This option removes the audio watchdog
signal (Section 2.10). The Minigas Mk5
remains silent except during the switch on
self-test sequence or in the event of alarms
or faults. It continues to provide a visual
watchdog signal.
Disable Negative Negative indications are displayed as -0.
Displays
1. GENERAL DESCRIPTION
#
#
#

MAN0585.P65 Issue 01 - 11/99
2987M5023
16
Option Brief Description
Go/NoGo Mode The display only indicates the sensors fitted.
When a hazardous condition is detected,
displayprovides an indication of the hazard (see
Section 2.11).
Manual AutoZero Instrument zero can be set during the first 60
seconds after switch on (see Section 2.8.2).
Long Oxygen This option supplements the AutoZero option
AutoZero by allowing the oxygen reading to be spanned
to 20.9% at any time.
Alarm Recurrence Allows the ART to be set to any value between
Time (ART) zero and 30 seconds. If the ART is zero, then
the alarm cannot be cancelled until the
hazardous condition clears.
Long STEL ART Allows nuisance STEL alarms to be removed
by extending the STEL ART (after cancelling)
toequal the STEL period (normally 15 minutes).
However, if the STEL level becomes safe and
then hazardous again within the cancel period,
the alarm repeats.
Non-latching Display backlight is switched on for only ten
Backlight seconds when the red button is pressed (see
Section 2.6).
Datalogging Allows, typically, up to 40 hours of exposure
data and alarms to be stored for later analysis
by downloading to a PC.
Available either as a fixed log, where logging
stops when the log store is full, or as a rotating
log where logging continues after the store is
full by overwriting the oldest data.
Also permits a calibration due date to be
programmed into the Minigas Mk5.
1. GENERAL DESCRIPTION
#
#
30s
#

17
MAN0585.P65 Issue 01 - 11/99
2987M5023
Option Brief description
Time-of-Day display Additional Display Mode screen, available on
datalogging instruments only, providing a
24-hour clock (see Section 2.7.4).
Countdown Provides an alarm signal at preset intervals
Stopwatch Alarm to remind the Minigas Mk5 user to carry out
specific tasks.
For example, lone workers in confined spaces
may be required to establish regular contact
with their control-centre in order to confirm
their safety (see Section 2.4.4).
Language Displays (and front panel label) are either in
English, French or German.
H2S Warning Displays a warning message to indicate that
the flammable sensor needs re-calibrating if
the H2S concentration has exceeded100 ppm.
Only available on CO2instruments.
Autogas Warning Disables sensor channel and displays a
warning if it fails autozero.
1. GENERAL DESCRIPTION
#
Eng

MAN0585.P65 Issue 01 - 11/99
2987M5023
18

19
MAN0585.P65 Issue 01 - 11/99
2987M5023
CAUTION
Theproceduresand cautions detailedinthe CSA andSAA
Approval Addendum on page 4 of this manual must be
observed when using the Minigas Mk5 in North America
or Australia.
2.1 INTRODUCTION
Thissection provides instructionsonoperating the MinigasMk5
and interpreting the screen displays, alarms, faults and error
warnings. Details of procedures to be used in the working
environment are provided in Section 3.
References are made in this chapter to optional facilities which
mayormay not be configuredinthe user’sinstrument. Toavoid
confusion, these are always referred to as software options,
further details of which will be found in Section 1.4.
Some of the operations described in this section include
instructions to apply short, medium or long duration presses to
the I/O (on/select) button on the left-hand side of the
MinigasMk5.In this context, shortisfor a single bleep,medium
is for two bleeps and long is for three bleeps.
2. USING THE MINIGAS MK5

MAN0585.P65 Issue 01 - 11/99
2987M5023
20
2. USING THE MINIGAS MK5
2.2 FRONT PANEL DISPLAY FORMAT
The main parts of the liquid crystal display are the four banks
of 7-segment digits. Display screens, showing the gas
concentration levels, use these banks as follows:
Upper left Oxygen (three characters).
Lower left Explosive gases(two charactersand
a negative sign).
Upper right Toxic 1 gas (three characters).
Lower right Toxic 2 gas (three characters).
The particular gas to which the concentration refers is printed
asa fixedlegend onthefrontpanellabel, adjacentto thedisplay.
To the left of the display are four arrows. These arrows are
used to indicate the information that is being displayed (for all
sensors)bypointing to the appropriatefixedlegend on the front
panel label. That is, INST ( ) (instantaneous), PEAK (),
STEL () or LTEL () (refer to the Glossary Appendix).
Left Alarm Light Right Alarm Light
I/O
On/Select
Button
Liquid
Crystal
Display Backlight
Button