Rosemount Analytical NGA 2000
REFERENCE
MANUAL
OTICE
N
The information contained in this document is subject to change without notice.
Rosemount Analytical's system of NGA 2000 Modular Gas Analyzers and Controllers are patented,
under U.S. Patent 5.787.015.
Excel™, Word™, Visual Basic™, Windows™ and Windows NT™ are trademarks of Microsoft Corporation.
MS-DOS® is a U.S. registered trademark of Microsoft Corporation .
Echelon® is a U.S. registered trademark of Echelon Corporation.
LONTALK™ and LonManager™ are trademarks of Echelon Corporation.
IBM® is a U.S. registered trademark of International Business Machines.
Manual Part Number 748384-B
August 1998
Printed in U.S.A.
Rosemount Analytical Inc.
4125 East La Palma Avenue
Anaheim, California 92807-1802
ONTENTS
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REFACE
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PURPOSE/SAFETY SUMMARY ........................................................................P-1
ECTION
S
1.1 INTRODUCTION ......................................................................................1
1.2 GENERAL INSTRUCTIONS.....................................................................1
1.3 SYSTEM SETUP ......................................................................................2
1.3.1 Basic Instructions........................................................................ 3
1.3.2 Binding ......................................................................................3
1.3.3 Advanced Instructions.................................................................5
1.3.4 Details ......................................................................................6
1.3.5 Troubleshooting .............................................................................8
1.4 ANALYZER MEASUREMENT RANGES.................................................. 9
1.4.1 Basic Instructions........................................................................ 10
1.4.2 Advanced Instructions.................................................................10
1.4.3 Details ......................................................................................11
1.4.4 Troubleshooting ..........................................................................11
NTRODUCTION
1. I
1.3.3.1 Analyzer Power ...........................................................5
1.3.3.2 Naming Analyzers ....................................................... 5
1.3.4.1 TAG.............................................................................6
1.3.4.2 Binding ........................................................................ 7
1.3.4.3 Controller Module Memory Issures .............................7
1.3.4.4 Replacing an Analyzer ................................................8
1.3.4.5 Multiple Control Modules.............................................8
1.4.2.1 To change range fullscale values....................................10
1.4.2.2 To alter the maximum or minimum possible ranges........11
1.5 ZERO AND SPAN GAS SETTINGS .........................................................12
1.5.1 Basic Instructions........................................................................ 12
1.5.2 Advanced Instructions.................................................................12
1.5.3 Details ......................................................................................13
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1.6 GENERAL ZERO/SPAN SETUP ............................................................. 13
1.7 ZEROING................................................................................................. 17
1.8 SPANNING ............................................................................................ 22
1. (
1.6.1 Calibrate ranges separately or together ..................................... 14
1.6.2 Calibrate ranges using an Autocal module ................................. 14
1.6.3 Troubleshooting.......................................................................... 15
1.7.1 Basic Instructions ....................................................................... 17
1.7.2 Advanced Instructions ................................................................ 18
1.7.3 Details ..................................................................................... 19
1.7.4 Troubleshooting.......................................................................... 20
1.8.1 Basic Instructions ....................................................................... 22
1.8.2 Advanced Instructions ................................................................ 22
1.8.3 Details ..................................................................................... 23
1.8.4 Troubleshooting.......................................................................... 23
CONTINUED
1.7.1.1 No Autocal Module ..................................................... 17
1.7.1.2 Autocal Module........................................................... 17
1.7.2.1 No Autocal Module ..................................................... 18
1.7.2.2 Autocal Module Present.............................................. 19
1.8.1.1 Set Span Gas Concentration ....................................... 22
1.8.1.2 Perform A Span ........................................................... 22
)
1.9 LINEARIZATION ...................................................................................... 24
1.9.1 Basic Instructions ....................................................................... 25
1.9.2 Advanced Instructions ................................................................ 25
1.9.3 Details ..................................................................................... 26
1.9.4 Troubleshooting.......................................................................... 27
1.10 LINEARIZTION TOUCH-UP................................................................... 28
1.10.1 Basic Instructions ..................................................................... 28
1.10.2 Details ..................................................................................... 29
1.10.3 Troubleshooting........................................................................ 30
1.11 RESPONSE TIME.................................................................................. 30
1.11.1 Basic Instructions ..................................................................... 31
1.11.2 Advanced Instructions .............................................................. 31
1.11.3 Troubleshooting........................................................................ 32
1.12 ANALYZER MODULE HISTORICAL DATA ........................................... 32
1.12.1 Basic Instructions ..................................................................... 33
1.13 ANALYZER ALGORITHM DESCRIPTION............................................. 33
1.14 SECURITY ............................................................................................. 35
1.14.1 Basic Instructions ..................................................................... 35
1.14.2 Troubleshooting........................................................................ 36
1.15 DATE AND TIME ................................................................................... 36
1.15.1 Basic Instructions ..................................................................... 36
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1.16 SCREEN APPEARANCE .......................................................................37
1.17 MANUFACTURING AND SERVICE DATA.............................................38
1.18 ANALYZER STATUS.............................................................................. 38
1.19 ANALYZER INTERNAL DATA STORAGE .............................................40
1.20 SERIAL I/O MODULE.............................................................................42
1.21 NETWORK ISSUES ...............................................................................43
1. (
1.16.1 Basic Instructions......................................................................37
1.18.1 Health (Alarm Status)................................................................38
1.18.2 Analyzer Operational Status .....................................................39
1.18.3 Analyzer Sampling Status .........................................................39
1.18.4 Analyzer Calibration Activity......................................................39
1.18.5 Analyzer Calibration Status.......................................................40
1.18.6 Analyzer Validity Status ............................................................40
1.19.1 Basic Instructions......................................................................41
1.19.2 Details ......................................................................................41
1.19.3 Troubleshooting ........................................................................42
1.20.1 Details ......................................................................................42
1.20.2 Troubleshooting ........................................................................43
1.21.1 LON Data ..................................................................................44
1.21.2 LON Data Details ...................................................................... 44
CONTINUED
)
1.22 MODBUS................................................................................................ 45
1.23 PC LON INTERFACE .............................................................................45
1.23.1 Performance .............................................................................45
1.23.2 Basic Operation ........................................................................46
1.23.3 Details ......................................................................................46
1.23.4 Using Excel with the DDE Server.............................................. 47
1.23.4.1 Basic DDE Points In Excel ........................................ 47
1.23.4.2 Spreadsheet Cell Formula.........................................48
1.23.4.3 To Get An Array Element ..........................................48
1.23.4.4 Reading A Variable ...................................................48
1.23.4.5 Establishing Analyzers Present.................................49
1.23.4.6 Writing To A Variable ................................................50
1.24 AK ......................................................................................................51
1.24.1 AK Example Using The Windows Terminal Emulator ...............51
1.25 ALARM I/O MODULE GENERAL INFORMATION .................................52
1.25.1 Setup Procedure ....................................................................... 52
1.25.1.1 Binding ......................................................................52
1.25.1.2 Setting Up Analog Output..........................................52
1.25.2 Details ......................................................................................52
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1.26 AUTOCALIBRATION MODULES........................................................... 53
1.27 SYNCHRONIZING AUTOCAL MODULES............................................. 55
ECTION
S
2.1 VERSION 2.2 ........................................................................................... 57
ECTION
S
3.1 VERSION 2.2 ........................................................................................... 165
PPENDIX
A
1. (
1.26.1 Troubleshooting.......................................................................... 53
1.26.2 Differences Between The System Autocalibration Module
1.26.3 Use Of The System Autocalibration Module And The Single
1.27.1 Basic Instructions ..................................................................... 55
2. A
3. I/O M
CONTINUED
And The Single Autocalibration Module........................ 54
Autocalibration Module ................................................. 54
)
NALYZER VARIABLES
ODULES VARIABLES
A. G
LOSSARY
NDEX
I
IGURES
F
1-1 Typical Menu............................................................................................ 1
1-2 Analyzer Algorithm................................................................................... 33
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REFACE
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URPOSE/SAFETY SUMMARY
P
This is a reference manual for the NGA series of analyzers. It contains in depth
discussion of the various features and operational elements of the analyzers, together
with information about their use with computers. It is not intended to be a stand-alone
document, but should be combined with the individual analyzer and platform manuals.
A major part of this manual is the description of the NGA variables. These are the
names of the packets of information that are communicated over the NGA digital
communication network, and are available for external access. It is vital that no
attempt be made to directly affect their values without a complete understanding of the
results of doing so. Serious damage to the analyzers may result from incorrect
assignments.
If this equipment is used in a manner not specified in these instructions, protective
systems may be impaired.
DANGER
personal injury, death, or substantial property damage if the warning is ignored.
WARNING
personal injury, death, or substantial property damage if the warning is ignored.
CAUTION
personal injury or property damage if the warning is ignored.
NOTE
important but not hazard-related.
To avoid loss of life, personal injury and damage to this equipment and on-site
property, all personnel authorized to install, operate and service this equipment
should be thoroughly familiar with and strictly follow the instructions in this
manual. Save these instructions.
is used to indicate the presence of a hazard which
is used to indicate the presence of a hazard which
is used to indicate the presence of a hazard which
is used to indicate installation, operation, or maintenance information which is
will
will
can
or
cause
cause
cause
can
severe
severe
minor
748384-B Rosemount Analytical August 1998
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REFACE
WARNING: ELECTRICAL SHOCK HAZARD
Operate this equipment only when covers are secured. Servicing requires
access to live parts which can cause death or serious injury. Refer servicing to
qualified personnel.
For safety and proper performance, this module must be connected to a
properly grounded three-wire source of electrical power.
WARNING: POSSIBLE EXPLOSION HAZARD
This equipment may contain modules used in the analysis of sample gases
which may be flammable. If used for analysis of such gases, the module must be
protected by a continuous dilution purge system in accordance with Standard
ANSI/NFPA 496-1993, Chapter 6.
WARNING: POSSIBLE HAND INJURY
Do not place hands or fingers in Platform front handles when the front panel is
open. Dropping front panel while hand or fingers are inside either handle can
cause serious injury.
WARNING: PARTS INTEGRITY
Tampering with or unauthorized substitution of components may adversely
affect safety of this product. Use only factory approved components for repair.
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NTRODUCTION
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1
1.1 INTRODUCTION
This manual provides detailed general information about the operation of the NGA
system. It is intended for the serious user or system integrator, or those writing
software that interfaces directly with the system.
Sections are arranged in a how-to fashion, each chapter normally having a basic,
advanced, detailed, and troubleshooting section.
Basic sections give the essential operational procedure
•
Advanced gives the complete procedure for analyzer experts
•
Details shows the inner workings of the analyzer
•
Troubleshooting gives some suggestions to help resolve problems
•
Some sections are not formally split in this fashion
•
This manual is intended to be used with the Platform manual, and also with each
individual analyzer manual, such as those for the CLD, FID, NDIR and PMD analyzer
modules.
1.2 GENERAL INSTRUCTIONS
Main Menu
Basic controls . . .
Expert controls and set up . . .
(Operational configuration)
Technical level configuration . . .
(Diagnostic and manufacturing/service)
DISPLAY PARMS. NEXT LOCK INFO
F
IGURE
1-1. T
YPICAL MENU
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The NGA menus have three separate paths, called
These paths are setup so as to separate the functions of the three main varieties of
personnel expected to use the analyzer systems, that is Operators, Engineers and
Maintenance Technicians. The security system outlined below is designed to restrict
access in this manner.
Basic menus allow an operator to perform the normal, simple analyzer functions such
as zeroing, spanning and changing ranges.
The expert menus allow an expert analyzer user to configure the analyzer as he
desires, and to perform the more advanced controls, as well as perform the basic
controls with more information and options allowed.
The technical menus provide control over the system operation, and access to the
manufacturing data, the service data and the diagnostic data.
These menus are found under the main three choices in the
In normal operation, the control module screen shows either a single analyzer display,
or the multiple analyzer display. From the latter you can select a single analyzer to
examine, by pressing the "SELECT" key twice.
basic, expert
Main menu
and
.
technical
.
From the single analyzer display you can either select the menus by pressing the
"'MENUS" softkey, or you can select a couple of screens that provide basic essential
information about the analyzer. Access these by pressing the "PARMS" (short for
parameters) softkey.
If you press the "MENUS" softkey, you will enter the
menus, has five softkeys labeled at its foot. In all menus other than this one (with a
few unintentional exceptions!) the button in the bottom left hand comer will jump you to
the
Main menu
screen for the menu you are on.
. The button in the bottom right hand corner will jump you into the help
Main menu
. This menu, like all
1.3 SYSTEM SETUP
The usual NGA system consists of a control module, one or more analyzer modules,
and one or more I/O modules. If you have only the one analyzer module, the system
will set itself up automatically, but if you have more than one you will have to give it
some instructions as to how to configure itself. In particular, you have to tell it which
analyzers are connected to which I/O modules.
If you have no I/O modules,. you can skip this section.
If you have more than one control module in a system, whether or not you have more
than one display in it, you will need to read the advanced section here.
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NTRODUCTION
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1.3.1 B
ASIC INSTRUCTIONS
Verify you have all the modules you are going to use, and that they are all connected
to the power supplies, and to the LON. Power connections are normally made through
the three pin connector on the front of each analyzer module, or through the audio
connector on the back of the platforms. You can power a single analyzer from the
internal power supply in a platform, but if you have more than one analyzer you will
need some sort of additional power supply, such as the 24V, 30 amp Bulk Power
Supply made by Rosemount Analytical. Each analyzer draws about 5 amps, so a 30
amp supply can handle about five analyzers.
WARNING: IMPROPER CONNECTION
The internal LON connection in the platform is for use with internally mounted
and powered analyzers only. Using this connection for external analyzers or
LON components could result in short-circuiting the 24V power supply through
the cable, with resultant damage.
1.3.2 B
INDING
You have to tell the system which I/O module is bound to which analyzer.
V
ERSION
Verify that all the analyzers and I/O modules are present:
Enter the
Enter Technical level configuration...
Enter Listing of all modules...
Verify they are all there. (Note that system Autocal modules are listed as five
separate modules.)
Enter the
Select Technical level configuration...
Select System setup..
Select Module binding...
2.2
CONTROL MODULES
Main menu
Main menu
.
(press "HOME" or "MENUS")
:
Verify that the analyzer listed on the
If it isn't, select
the
Analyzer module selected
748384-B Rosemount Analytical August 1998
View bindings...
: line.
Analyzer module selected
. press "NEXT" until the desired analyzer is shown on
: line is the correct one.
NGA Reference Manual
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INTRODUCTION
Press the left arrow key to return to the
Select the desired module. You will jump back to the previous menu.
Check that the I/O module selected is correct for the analyzer shown - NOT the
analyzer at the very top of the screen!
Press "BIND".
Wait while the system restarts, and then re-enter the binding menu.
Repeat the procedure for each I/O module until all are bound.
Note: If you have made a mistake, press "UNBIND". Then repeat the binding
procedure.
V
ERSION
Verify that all the analyzers and I/O modules are present:
Enter Listing of all modules...
2.3
CONTROL MODULES
Module binding
:
menu
Verify they are all there. (Note that system Autocal modules are listed as five separate
modules.)
Enter the
Select Technical level configuration...
Select System setup..
Select Module binding..
Note that each analyzer is listed on this screen. For each in turn, select the analyzer.
Press the right arrow key.
Select, from the list of I/O modules shown, one module to be bound to the analyzer.
Press the ENTER key. Continue until all desired I/O modules are selected.
Press the BIND softkey.
Verify that all the analyzers and I/O modules are present.
Main menu
(press "HOME" or “MENUS”).
Note: To unbind particular I/O modules, select them in the Module binding menu, and
press UNBIND.
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1.3.3 A
DVANCED INSTRUCTIONS
1.3.3.1 A
The quality of the analyzer power is important. It must be within a couple of volts of
24 V, and it must be reasonably quiet. 100 mV of noise is adequate. Earlier analyzers
required inrush current limiting if the leads supplying power were longer than a couple
of feet. Later analyzers (with the CE mark) were not as touchy. If such protection was
not provided, the analyzers might blow fuses upon start up. In this case, replace the
fuse and try again. Don't plug in the analyzer power while it is turned on.
1.3.3.2 N
Verify the I/O modules are named appropriately. You want to be able to tell which I/O
module is which, so you can bind it to the appropriate analyzer. The variable TAG is
used for this. Later I/O modules are able to tell which slot they are plugged into on the
control module Backplane, but most I/O modules cannot do this, and so they rely on
your knowing which one they are in some other way.
An easy way to do this is as follows:
Plug the I/O modules into the platform one by one. Do this with no analyzers
connected.
NALYZER POWER
AMING ANALYZERS
Power up the Platform.
Press the button marked "RE-INIT" as the control module initializes itself.
When it is showing its main display, press the button marked "MENUS".
Select
In the resulting menu, select
Select the listed I/O module.
On the bottom line of the resulting menu edit the I/O module tag to something that you
will recognize.
Do this for each I/O module in turn. Then reconnect the whole system, including the
analyzers, and again press the “RE-INIT” button.
Verify you know which analyzer is which. Normally this is easy, but if you have several
examples of the same kind of analyzer, you will need to verify they are named
appropriately.
You can do this even though all the analyzers are hooked up at once, since you can
look at them and see what their serial numbers are.
Technical level configuration...
Listing of all modules...
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From the main screen, press "MENUS"
Select
Select
Select
Select Analyzer module data. Read Analyzer module s/n: and determine which
analyzer you are looking at.
Edit the
the heading on the top of the screen for the analyzer you are looking at. This line
won't change until you enter another menu, but the analyzer will remember whatever
you enter, up to 31 characters.
Press "HOME".
Press "NEXT" (it selects the next analyzer in its list.).
Repeat the procedure for the new analyzer.
An alternative is to start the Rosemount Analytical DDE server program in a PC
connected to the system. When it has completed its network interrogation, open the
DDE server program icon and click on "File". Select "Nodelist". Click on each
module's TAG in turn, and edit them as you like. Then exit and restart the DDE server
before attempting to use any application with it.
Technical level configuration
Service menus...
Manufacturing data...
User tag number:
line to make the tag whatever you want it to be. The tag is
...
1.3.4 D
ETAILS
1.3.4.1 TAG V
All modules use the variable called TAG to contain their name. Modules also have a
node name, and a program id, and these are used internally in the LON. They are not
normally accessible externally, though both may be used by non-NGA LON nodes
such as a PC setup to monitor the NGA system.
Analyzer Modules also have a serial number in their variable AMSN. This should
match the serial number assigned to the analyzer and visible on a label on their sides.
The control module puts the contents of TAG onto the main display screens, and also
onto the top line of the menu screens. It regards menus as belonging to an analyzer,
the one selected in the main screen or selected by pressing the NEXT button in higher
level menus. The TAG and the present time reading are always displayed on the top
line of every menu screen.
ARIABLE
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Note
TAGs should be kept as short as possible, and should not contain blanks,
dashes or other mathematical signs. This will avoid problems when using a PC
to interface with the module.
The gas measured is shown in the variable GAS. This is normally straightforward, but
in the case of the FID you should verify that this variable is matched with the response
factor, whether the analyzer is measuring in C1 or C3 (methane or propane) units, for
example.
The analyzer sensitivity is described in coded form in its bench code (AMBC).
Particularly in the case of NDIR analyzers, the bench has to be setup for the analysis
desired.
Individual analyzers may also have internal serial numbers reported in other variables
visible in their
Network variables: TAG, AMSN, AMBC, GAS, CARBON_ATOMS.
Manufacturing data screen.
1
1.3.4.2 B
Binding is the process of connecting various variables in the analyzer module with
equivalent variables in the I/O modules. Normally the LON expects to bind individual
variables, but the NGA system simplifies this by binding whole groups of them at once.
Once they are bound, an update to one variable on one node will automatically cause
the variable bound to it on another node to be updated as well. This allows the I/O
module to track the main reading (PVA) of the analyzer automatically, and it allows the
I/O module to change the range of the analyzer by updating its CRANGE0 variable,
thus changing the analyzer's CRANGE variable which is bound to CRANGE0.
Subsequent revisions of the control module software (from V2.3) will allow you to bind
all the I/O modules at once, rather than making you bind each one, waiting for the
system to reset between each module.
Binding is only necessary for systems with I/O modules. Systems that have no control
module, and which rely on a computer to get data from analyzers, do not need to do
any binding.
1.3.4.3 C
The control module has a restricted amount of memory, just as do all computers. It
can therefore handle only a certain number of analyzers and I/O modules. It stores all
of the data from each module within itself. If an analyzer module is removed and
replaced, the control module will remember the data from the analyzer, so if the
analyzer is replaced the control module can recognize it and bring it back on line
immediately. However this also means that the control module will remember all the
INDING
ONTROLLER MODULE MEMORY ISSUES
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INTRODUCTION
analyzers it has ever seen, so that it will eventually run out of memory. The limit with a
V2.2 control module is about 6 analyzers. With a V3.0 control module it is 15
analyzers.
1.3.4.4 R
If you replace an analyzer with a new one, you will have to reset the control module so
that it can recognize the new analyzer. If you run out of memory in the process, the
control module may hang and not complete the initialization. In this case, press the
"RE-INIT" button and rebind all the I/O module all over again. If the control module is
so lost that the "RE-INIT" button doesn't work, remove power from it briefly and
replace the power, and then press the "RE-INIT" button as soon as it appears. Then
go through the binding process again.
This procedure should be improved with the V3.0 control module software.
1.3.4.5 M
In V3.1 or earlier, it is not possible to connect more than one control module on a
system. If it is desired to connect them to a single computer, it is necessary to use
"Routers" (a component sold by Echelon Corporation) to isolate the control modules
from each other.
1.3.5 T
ROUBLESHOOTING
EPLACING AN ANALYZER
ULTIPLE CONTROL MODULES
Control module hangs up during a reset…
Control module out of memory. Press "RE-INIT" button, or remove power, replace
power and then press "RE-INIT" button.
You may have several analyzers updating their readings as fast as they can,
saturating the network. In this case, only connect up one at once, and when it comes
up, set its LON update rate to 10 per second or once per second. See "Response
time" below. Then hook them all back up and try again. Don't forget to remove the I/O
modules while you do this - if they were not already bound, they will all bind
themselves to the first analyzer you try this with.
"RE-INIT" button doesn't work…
Control module crashed. Remove power, replace power, then press "RE-INIT" again.
Even after power up, "RE-INIT" button doesn't work…
Battery backed RAM is corrupted. Open the control module, remove the jumper next
to the battery (the cylindrical object above the board at the near end - the jumper is
8
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
NTRODUCTION
I
just next to the positive end's wire connection to the board); wait for two minutes,
replace the jumper and replace the board in the control module. Then press "RE-INIT"
when power comes up.
I/O doesn't respond to the analyzer signals…
The I/O modules aren't bound. This happens after a "RE-INIT". Don't press this
button unless you mean it! You have to go through the binding procedure again. You
may have bound all the I/O modules to one analyzer by powering the system up with
only one analyzer connected, but all the I/O's connected. If so, press the "RE-INIT"
button and start again. The LON may be saturated. Try reducing the LON update rate
of all the analyzers to 10 per second. After a short time the I/O modules should
respond once again.
Several I/O's have the same name…
New I/O modules are all called the same thing. In order to tell the difference between
them, you have to name them. See the procedure earlier in this.
1
Later I/O modules can tell which slot they are plugged into. You can use this
information to identify them. It is located in the same place as the I/O tag name, under
"Listing of all modules.."
1.4 ANALYZER MEASUREMENT RANGES
NGA analyzer modules have four ranges available. These ranges normally do not
correspond to any physical settings in the analyzer, they are there for operator
convenience. It is possible to separately zero, span and linearize each range, in which
case you may well not get the same reading on a given gas, if you change the
operational range. Some analyzers do change an internal setting on a range change,
though they never do this dynamically based on the signal within a range. If they do
this, or if the filtering time is set to a value greater than zero, there will normally be a
short term "glitch" as the analyzer reaches its new value.
The dynamic range of the analyzer on a single range is normally quite great, and it is
often only necessary to change ranges if you are recording the analog output of the
I/O module. However for traditional reasons some users like- to operate between 20%
and 80% of a range, and thus change ranges anyway, even though this makes no
actual difference to the analyzer's operation or resolution.
It is possible to set the I/O module to produce an output independently of the
analyzer's current range. You can make the I/O module stay on a particular range,
regardless of the analyzer, or you can make the analyzer stay on a particular range
and force the I/O to change its ranges in response to a remote (digital line) command.
You can connect two or more I/O's to a single analyzer, and make them respond to
different analyzer ranges, thus getting two simultaneous outputs, one for low range
748384-B Rosemount Analytical August 1998
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INTRODUCTION
resolution, and the other for upset conditions.
If you make the I/O operate independently of the analyzer, it will change its output
range within about 120 micro seconds of a remote command (for an I/O with a 5 MHz
clock, later I/O's with a 10 MHz clock respond within 80 micro seconds). There is no
"glitch" at all in this case, since the analyzer is not affected by the range change
request.
If the I/O has to make the analyzer range change, the total transaction may take up to
half a second, and there may be a glitch in this time.
In general the only reason for making a real range change is to use a different
linearizer curve on a lower signal. It may also be useful to get a better signal to noise
ratio if the range change is drastic, such as changing from 0 - 10,000 ppm. to 0 - 10
ppm on a FID. On the former range the resolution is about 0.1 ppm, whereas on the
latter it is about 0.01 ppm.
1.4.1 B
1.4.2 A
ASIC INSTRUCTIONS
1. Enter the
2. Select
3. Edit the
DVANCED INSTRUCTIONS
1.4.2.1 T
1. Enter the
2. Select
3. Select Analyzer module setup.
4. Select
5. Select
Main menu
Basic controls...
Measurement range number:
O CHANGE RANGE FULLSCALE VALUES
Main menu
Expert controls and setup
Gas measurement parameter
Range setting
line
.
s..
s.. .
10
6. Edit the range upper and lower setpoints as desired.
7. Press the left arrow key.
8. Select
9. Edit any linearization parameters you have to due to the range change, such as
which linearizer is used on which range, or what the linearization coefficients are.
Linearization parameters
...
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
NTRODUCTION
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1
1.4.2.2 T
1. Press "HOME" or enter the
2. Select
3. Select
4. Select
5. Select
6. Edit the minimum and maximum ranges as desired.
1.4.3 D
ETAILS
The analyzer won't let you edit the fullscale range to a value higher than the maximum
range, or lower than the minimum range. Outside these bounds the analyzer won't
meet its specifications, probably. Only edit these if you have made a hardware
change to the analyzer so that it can now cover a new range.
If you increase a range by more than 10% without changing the linearizer range, the
analyzer will disable that linearizer. However, don't simply increase the linearizer
range to avoid this - the coefficients must be changed as well, or you will have linearity
errors.
O ALTER THE MAXIMUM OR MINIMUM POSSIBLE RANGES
Main menu
Technical level configuration
Service menus...
Manufacturing data...
Analyzer module data.
.
...
Any bound I/O module will get its ranges from the analyzer, you don't have to change
them in the I/O module as well.
Network variables: RNGHI, RNGLO, CRANGE, CURRENTRNGHI,
CURRENTRNGLO, MAXRANGE, MINMANGE, LINRNGHI, LINA0_, LINA1_,
LINA2_, LINA3_, LINA4_
1.4.4 T
ROUBLESHOOTING
I changed a range and now my linearity is wrong…
You have to change the linearizer parameters if you change a range value. You can't
use a linearizer that covers less than 90% of the range you axe on. Either select the
linearizer from the next higher range, or re-linearize the present range.
It won't let me make the range bigger (or smaller)…
You have reached the editing limits set by the minimum range or the maximum range.
You probably should not be setting the ranges outside of these limits. If you have
made a physical change to the analyzer, or you are willing to live with the lower
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INTRODUCTION
specifications, you can edit the minimum or maximum ranges in the
screen.
data
Manufacturing
1.5 ZERO AND SPAN GAS SETTINGS
It is essential that the zero and span gases are correctly described to the analyzer. It
zeros and spans by making the reading it is getting from its measurement signal equal
to what it has been told is the zero or span gas value. If it is zeroing or spanning
ranges separately it may well produce bogus answers if the zero or span gases are
entered incorrectly.
Zero and span gas values are entered into the Calibration gases menu under Expert
controls and setup.
1.5.1 B
ASIC INSTRUCTIONS
Select the analyzer you want to zero.
Press "MENUS" or "HOME" to enter the
Select Expert controls and setup
Select Analyzer module setup…
Main menu
.
Select Calibration gas list…
Edit the zero and span gases until they refer to the values on the bottles.
Press "HOME" to return to the
1.5.2 A
DVANCED INSTRUCTIONS
Zero gases are normally simply of zero concentration, but in some cases it is desirable
to "zero" off a non-zero gas. In this case, it may be necessary to iterate between zero
and spanning a few times until the results are accurate enough.
Gas cylinders are notoriously inaccurate. Even when they are specified at ±2%
certified accuracy, you can still have considerable errors. Some users prefer to zero
and span off gases of mediocre quality, but to "name" the gases by comparison with a
known high precision reference gas. In this case, carefully zero and span the analyzer
on the reference gas, and then measure the "span" gas with the analyzer. Enter the
result as the span gas "name" both on the bottle and in the
it is time to replace this bottle, "name" the replacement in the same way.
The span value has to be between 20% and 110% of the fullscale range. Ideally it
should be about 80% of the range.
Main menu
.
Calibration gas list
. When
12
The FID analyzer can be set to be calibrated on various kinds of hydrocarbons, such
as methane or propane. Its response factor must be adjusted accordingly. On the
same
Calibration gas list
screen, the FID includes a line marked
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
Calibration gas HC
NTRODUCTION
I
1
response factor:.
propane. The analyzer will then regard the span concentration as referring to that kind
of gas.
1.5.3 D
ETAILS
The analyzer compares its reading on the span or zero gas with the value entered into
the
Calibration gas list
zero and span factors so as to make its reading correspond to the value entered as
the span or zero gas concentration. It is therefore vital that the value entered be
correct.
The
Calibration gas list
away from the lower skilled operators. Entry of an incorrect value will completely
invalidate the analyzer's readings thereafter.
Network variables: SPANGAS, ZEROGAS, NOSPANGAS, NOXSPANGAS, ZERO,
SPAN, CARBON_ATOMS, NO_NOX
Edit this to the desired response factor, 1 for methane, 3.14 or so for
value for the range it happens to be on. It adjusts its internal
is located under the
Expert controls
menu so as to keep it
1.6 GENERAL ZERO/SPAN SETUP
During a zero or span the analyzer reads the signal from the gas detector, calculates
the apparent gas level, compares it with the desired level as entered in the
gas list
error value of the desired value. The error is 0.02% of the upper range value.
During the calibration sequence the analyzer monitors the reading over a period of
time set by the CALTIME variable, located in the
under Analyzer Module setup .... If it detects a drift of the reading, it will wait for a
longer time until the reading is stable, or until the time out period set by CALTIMEOUT,
also located in the
normally set at about 2 minutes. The analyzer will perform its zero or span anyway at
the end of the timeout time.
If the gas value is wrong, or the analyzer has drifted excessively, the analyzer will
check the reading on the calibration gas against the named value in the
gas list
analyzer is set to ignore limit checking, it will calibrate anyway, unless the span gas
value is outside the allowed range of 20% - 110% of the range value.
You can select whether to zero or span all the ranges together or separately. If you
make them separate, unless this is the first time that this analyzer has ever been
calibrated, it will only zero or span the range that you are on. Other ranges will not be
affected. If you elect to zero or span them together, the results will depend on the gas
values and the range values already set in the analyzer.
, and modifies the internal calibration factors until the reading is within a small
Calibration parameters.
Calibration parameters
, and if it is set to check its limits, it will not calibrate. Conversely, if the
menu as Calibration time out: This value is
Calibration
screen
Calibration
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INTRODUCTION
If the ranges are all zero based, and the zero gas is of zero concentration, the
analyzer will have no difficulty zeroing all the ranges at once. It does this by changing
the range to range 1, zeroing it, changing to range 2, waiting for stability and zeroing
that, and so on.
When it tries to span the ranges, if the span gas is above 10% and below I/O% of the
range value on any range, it will span that range, but if not it will not perform a span.
Thus if the span gas is 900 ppm, and the ranges are 10, 100, 1000 and 10,000 ppm,
and you are on range 3 (0 - 1000 ppm), it will only span range 3, even if you tell it to
span all the ranges together. In general, with widely spaced ranges such as this
example, it is best or indeed essential to span the ranges separately.
Bear in mind that the NGA analyzers have very good linearity and dynamic range, and
it is normally quite practical to operate them over a dynamic range of 30:1 or more on
a single range, if you are using a digital output.
1.6.1 C
1.6.2 C
ALIBRATE RANGES SEPARATELY OR TOGETHER
From the
Select
Select
Select
Edit the zero and span calibration lines as desired.
There are two Autocal modules available for the NGA systems (other than the
on-stack sample control module). One of them is designed to work with a single
analyzer, and to calibrate individually its separate ranges, the other is designed to
work with up to four analyzers, providing up to four span gases to span any number of
analyzer ranges. You can set these modules up to zero and span the analyzers on a
timed basis, and you can make them perform a zero or span or both at will. You
achieve the latter by entering their control screen, under
then
setup the module to zero and span as you desire, you can simply press the "START"
button and it will put the gases on the analyzer(s), wait the appropriate time, zero them
and span them. It is a common error to assume that the analyzer basic controls
"ZERO" and "SPAN" buttons will make this happen - it won't, you have to control them
from the auxiliary module controls as described above. A future version (post V2.2) of
software will rectify this automatically. See the Autocal module manuals for details on
how to set them up.
Main menu
Expert controls and setup
Analyzer module setup
Calibration parameters
ALIBRATE RANGES USING AN AUTOCAL MODULE
Auxiliary module controls
:
Expert controls and setup
.. ., then select the Autocal module. If you have already
14
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NTRODUCTION
I
Network variables: CALTIME, CALTIMEOUT, ZERO, SPAN, AMFN,
CALCHKLIMITS, ZERORNGS, CALRANGES, CALFAIL, CALFPC
1
1.6.3 T
ROUBLESHOOTING
Analyzer will not zero…
Verify you have a real zero gas; verify that the zero gas in the
to whatever the zero gas really is.
See the
line marked
If the analyzer has been changed in some way, so that its zero reading is quite
different from what it should be, verify that the limits checking is turned off in the
Calibration parameters
Verify the limits checked for are reasonable in the
If all else fails, get into the
Expert analyzer controls...,
for the range you are using. You can read the raw signal for the zero gas at the
bottom of this screen. If you edit the
signal, you will effectively zero the analyzer.
Result..
menu in the Expert controls section under Zero/span calibration. The
Result of last zero
menu. Zero it, then turn the limits checking back on.
: should give you a hint as to what happened.
Calibration parameters
Factors
"CAL" softkey, "FACTORS" softkey, and then select factors
menu. Find this under
Zero factor:
number to be the same as the raw
Calibration gas list
menu.
Expert controls and setup,
is set
You can see what the stored zero and span factors were by pressing the softkey
marked "HISTORY". If desired, you can load the stored or the manufacturing values
into the current values by pressing one or other of the two RSTR ... softkeys. This will
at least bring the analyzer back to the calibration factors it used to have. When you
are satisfied that you do have a good calibration, you can store the values into the
Stored values
If you have made a large span change, the zero may be offset excessively. In this
case simply redo the zero and span again.
variables by pressing the "STORE" button on the factors screen.
Analyzer will not span correctly…
See the
details.
The values of the span gases must be entered correctly. See the discussion
elsewhere about errors in span gas bottle naming. It is easy to replace a span gas
bottle, but to forget to enter the new span gas values, and therefore to get an
inaccurate span. You can guard against this to some degree by enabling the
Analyzer will not zero
paragraph above. In addition, there are a few additional
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INTRODUCTION
calibration error checking, and setting the failure margin to a low enough value to
avoid the worst mistakes. However this may mean that the analyzer will not be able to
calibrate itself due to normal drifts, temperature excursions etc.
If the analyzer has excessive noise, it may not span to the correct number. In this
case it is necessary to troubleshoot the analyzer itself.
The fullscale range value must be within 90% to 110% of the linearization range value,
or the linearizer will not be allowed to apply. In this case, the span may be wrong.
Also the linearizer curve must be monotonic between -5% and +110% of the fullscale
range.
The analyzer will not span at all…
The span gas value must be within 20% to 110% of the fullscale range value. If it is
outside these limits, the analyzer will simply not span. Change the fullscale range
value, or the span gas value if that is wrong, so that you are within these limits.
The calibration limits are enabled, and the span drift is greater than that allowed.
Disable the limits and try again, or make the limits wider and try again.
You expect the Autocal module to put a span gas on the analyzer, but you have
pressed the SPAN button in the
controls the analyzer, it doesn't control the Autocal module. If you press it, you have to
verify the gas is present first! If you want to use the Autocal module to control the gas
flow, you have to get into the Autocal module control screen under Expert controls,
then auxiliary module controls.
Basic controls
screen. The Basic controls screen only
One range calibrates, but others don't…
You are probably trying to span all ranges together when the analyzer cannot do it.
Set the analyzer to span ranges separately, and span each range on its own span gas.
Alternatively, if you only want to operate on one range, set all the ranges to the same
fullscale value, then it won't matter which range you are on and you can span them all
together.
Nothing seems to work, I'm lost…
We have put a back-up, fail-safe into the design. There are enough settings and
special circumstances that it is quite possible for both you and the analyzer to get
confused, particularly if you have modified the analyzer hardware or software in some
way.
16
The first back up is to put the last stored calibration factors back into the present ones,
by getting into the "Range (n) factors" screen for the range you are on, and then
getting into the "HISTORY" screen. Press "RSTR ST" to put the last good factors into
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
the present set. Alternatively you can restore the manufacturing factors with "RSTR
MN".
This won't do you much good perhaps if you have changed the hardware, since the
conditions may be very different now. In this case, you can get into the factors screen
for the range you are on, and manually edit the factors on zero gas (edit the zero
factor) and span gas (edit the span factor). Usually, you can just make the reading
approximately right, and then do a zero or span using the softkeys in the calibration
screen.
1.7 ZEROING
Zeroing is the function of adjusting the analyzer's offset so that when given a zero gas,
it reads zero, no matter how the analyzer span is set. By extension this includes
adjusting the low end of a suppressed range, although in this case the span setting will
have an effect on the low end reading.
NTRODUCTION
I
1
1.7.1 B
ASIC INSTRUCTIONS
1.7.1.1 NO A
Select the analyzer you want to zero.
Flow zero gas through the analyzer.
Press "MENUS" or "HOME" to enter the
Select
When it is stable, press "ZERO".
Press "ZERO again on the "
Press "HOME" to get back to the
Basic controls...
1.7.1.2 A
Select the analyzer you want to zero.
UTOCAL MODULE
Are you sure?"
UTOCAL MODULE
Main menu
screen.
Main menu
.
.
Press "MENUS" or "HOME" to enter the
Select
Select
Select the Autocal module, whatever you have called it.
748384-B Rosemount Analytical August 1998
Expert controls and setup
Auxiliary module controls...
Main menu
.
NGA Reference Manual
17
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INTRODUCTION
Either do a complete auto-calibration from the first screen that appears (by pressing
"START"), or
Select
Set the
Select the correct range to zero with
Select CAL in the
Press "START".
You can press "ABORT" to abort the calibration, and then press it again to cut short
1.7.2 A
1.7.2.1 NO A
Select the analyzer you want to zero.
Flow zero gas through the analyzer.
Enter the
Manual calibration function...
Gas to be used for calibration:
Calibration or QC check:
the sample purge time if you want.
DVANCED INSTRUCTIONS
UTOCAL MODULE
Main menu
.
to "Zero gas".
Measurement range number:
line.
Select
Select
Select the range you want to zero.
Verify gas flow.
Press CAL or select
Press "ZERO".
Press "ZERO" again.
Press the left arrow.
Select
Examine the
If desired, press the left arrow key to return to the calibration screen.
Expert controls and setup
Expert analyzer controls...
Zero/span calibration...
Result…
Calibration results
screen to see how well you did.
18
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NTRODUCTION
I
Press "FACTORS".
Select the calibration factors for the range you are on.
View the factors, and if desired, edit the "Zero factor" to the raw signal number shown
on the bottom of the screen. This will produce a zero output on the gas you have
flowing.
1
1.7.2.2 A
Select the analyzer you want to zero.
Enter the
Select
If you have not configured the Autocal module, do so.
Select
Press "START".
Alternatively, select
Select the gas desired, the range desired and the operation desired, then press
"START".
1.7.3 D
ETAILS
Certain analyzers can take a long time to get a good zero reading. If the analyzer has
been exposed to a high level gas, it may take many time constants to get down to zero
again. This means that you should be careful about doing a "Zero - span - zero"
check: the analyzer may not read the same thing on the second zero, simply because
it has not had a chance to get back to it. The NGA analyzers are capable of reading
gases with a great deal of precision, so you can easily see if the zero reading is not
correct, and this can be confusing.
UTOCAL MODULE PRESENT
Main menu
Expert controls and setup
Auxiliary module controls...
.
Manual calibration...
Two kinds of analyzer are particularly prone to zero problems. FID analyzer measure
hydrocarbons, and they are more responsive to high molecular weight hydrocarbons
than anything else. Oils, in particular, produce high readings due to the large size of
the molecules. If there are oils or other high molecular weight hydrocarbons in the
sample system, they will stick to the sample tubing walls and take a very long time
indeed to evaporate away. If you expose the analyzer to a really high concentration of
such materials, such as by spilling gasoline near the sample intake, you may have to
disassemble it and clean all the plumbing before it will read a good zero again.
The symptom of hydrocarbon contamination is that the analyzer reads high on zero
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INTRODUCTION
gas, and this reading very slowly decays over a matter of weeks. You can speed up
the process by cleaning out the tubing with alcohol and distilled water, or by flowing
argon through it while heating the tubing to red heat with a flame. Needless to say,
this should not be done to Teflon tubing! You should use stainless steel components
and tubing, and the tubing should be cleaned before use. Otherwise, if you do use
Teflon or copper tubing, and you do not take precautions, you will suffer from this
bleeding down effect for a long time.
Trace oxygen and water vapor analyzers have similar zero problems. Both water
vapor and oxygen are present in the air at very high vapor pressures, and thus will
leak or diffuse into sample systems with great ease. Water vapor will stick to walls
even worse than hydrocarbons do, and may take many weeks to be removed. Both
water and oxygen will readily diffuse through any plastic components, and you will not
be able to reach levels around 1 ppm unless you make the entire sample system out
of stainless steel, including valve and regulator diaphragms. Even when you have
made the sample system perfect, you will find that getting down to sub 1 ppm levels
may take several days. After exposure to air for a short time, for example while
replacing a sensor, the system may take a day to come back to zero.
For these reasons, zeroing trace analyzers is not an easy thing to do. If you go ahead
and zero them anyway, you may find that you get negative readings as the sample
system cleans out, and your readings around the zero point may be quite unreliable.
Trace levels around the 10 ppm value are normally comparatively unaffected by the
above considerations, unless you have made a gross error in the sampling system.
You should take the above warnings very seriously if you are trying to measure in the I
ppm or less band.
If you think that you are not getting good results at these low levels, the reasons are
almost invariably due to sample contamination. Make sure you rule out any possible
sources of contamination before deciding that you have an analyzer problem.
Network variables: CALTIME, CALTIMEOUT, ZERO, SPAN, AMFN,
CALCHKLIMITS, ZERORNGS, CALRANGES, CALFAIL, CALFPC
1.7.4 T
ROUBLESHOOTING
Zero drifts down over time…
20
If a FID, or trace 02, analyzer, you have sample contamination. In the case of the FID,
you must determine where the contamination is coming from, possibly by connecting
zero gas directly to the sample inlet, using new ultra-cleaned stainless steel tubing,
and verify that the analyzer itself is not contaminated. If it is, it will clean itself out in
time if you leave it, but if this is not practical, you have to send it back to the factory for
disassembly and cleaning. Otherwise, replace your tubing with stainless steel, and
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
NTRODUCTION
I
clean all the sample components, preferably with a blow torch while flowing argon gas
through it.
For oxygen analyzers, an elevated zero means a leak. Remember that oxygen
diffuses through any kind of plastic. Also remember that it is the partial pressure
difference that controls the diffusion rate - the fact that your sample is at 3000 psig
means nothing to the oxygen atoms. To them, a bottle of pure nitrogen is a vacuum,
and they whistle into it if given a chance. It is normal for an oxygen analyzer to take a
day or two to come to a good zero reading, leave it for a while and see if it stabilizes
before worrying.
You can test for leaks by shutting the sample flow off both upstream (first!) and
downstream of the analyzer. The oxygen reading should stabilize at a low level of a
ppm or so, if it goes up to a significant level you have a leak.
After a zero, the reading is very erratic…
Put a span gas in and see what it reads. If you have spanned on a zero gas, with the
calibration limits disabled, you will have made the span setting much too sensitive. In
this case, verify you do indeed have span gas in the analyzer, and span it again
(disabling the limit checking first), then zero it again.
1
Similarly, if you have zeroed with a span gas, zero it with a real zero gas and re-span,
then zero again. Now enable the limit checking so this doesn't happen again.
It refuses to zero…
Verify you do have a real zero gas in the analyzer, and disable limit checking. Then
zero it again. Also, zero on all ranges independently.
After a span, it won't go back to zero…
Leave it on zero gas for a long time, at least a hundred times the response time of the
analyzer. See if it made it back to zero again. If not, check for leaks of span gas into
the zero gas. If the zero is now lower than it was before, i.e. negative, re-zero and
then re-span. If it is higher, and the previous zero happened within a few minutes,
something is wrong with the zero gas, the sample system, or possibly the analyzer. If
the analyzer temperature has changed, such as by opening a door and allowing cold
or hot outside air to blow on the analyzer, let its temperature stabilize again and try
again.
It may be that the analyzer span is now very different from before. Check your span
gas for correctness, and that you did indeed have flow of gas during the span. If all is
well, re-zero and then re-span.
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INTRODUCTION
1.8 SPANNING
Spanning is the function of adjusting an analyzer's measurement gain such that a near
fullscale gas reads correctly. Since this reading depends on the zero, it is essential
that you perform a zero before a span. It is also essential that you verify that the span
gas value has been entered correctly in the calibration gas screens.
Linearization is the function of making sure that the readings in between the zero and
span point also read correctly. See the section below for this.
1.8.1 B
ASIC INSTRUCTIONS
1.8.1.1 S
Get into the
Select
Select
Select
Change any zero or span gas concentrations as desired. (Span gas values must be
within 20 - 120% of the range fullscale.)
1.8.1.2 P
Get into the
Flow the appropriate span gas through the analyzer.
Select
ET SPAN GAS CONCENTRATIONS
Main menu
Expert controls and setup
Analyzer module setup.
Calibration gas list..
ERFORM
Main menu
Basic controls...
.
A S
.
PAN
Verify sample gas flow.
Press "SPAN", then "SPAN" again.
Press the left arrow or "HOME" when you are done.
1.8.2 A
As per basic controls, except do the span through the
menu.
Enter the
Flow the appropriate span gas through the analyzer.
22
DVANCED INSTRUCTIONS
Main menu
.
Expert controls and setup
August 1998 Rosemount Analytical 748384-BNGA Reference Manual
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