AMI 201RSP User manual

AMI Analyzer Manual Contents •
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AMI
Oxygen Analyzer Manual
Model 201RSP
AMI, Costa Mesa, CA

AMI Analyzer Manual Contents •
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Contents
Preface 1
The AMI story 1
Caution 1
Address 1
Model 201RSP Oxygen Analyzer 2
Introduction 2
Features: 2
Oxygen sensor: 3
Sensor Warranty: 3
Instrument Warranty: 3
Recei ing the analyzer 3
Important: 4
-------------------------Points to consider first! ------------------------------ 4
Installation and Operation
Recei ing the analyzer 6
Installation. 6
Location: 6
Short-form Installation Procedure 8
Laptop set up procedure: 10
Expanded Installation Procedure 11
Interconnections: 21
Alarm connections: 21
Output connections: 21

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Serial connections: 22
Sample Handling: 23
Operation 24
General Description: 24
Security: 24
Front Panel Controls: 25
Output Ranges 25
View Output Range 25
Change Output Range 25
Alarm Set Points 25
View Alarm Set Points 26
Change Alarm Set Points 26
Alarm Hold Off 26
Calibration (Spanning) 26
Verify Span Factor: 27
Read the Temperature: 27
Alarm Functionality: 28
Communications 30
Basics 30
USB communication: 30
Communication program: 31
Top section: 32
Analyzer Info Section: 32
Analyzer Setup Section: 33
Sensor Calibration Data: 35
Data Logging 36
Variables: 38
RS-485 Modbus Introduction: 39
RS-485 Modbus Communication: 40
O er iew: 40
Commands: 40
The Oxygen Reading: 41
Other readings: 41
Diagnostic Functions 47

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Maintenance and troubleshooting 48
Maintenance: 48
Periodic Calibration: 48
Sensor Replacement: 48
Sensor replacement cautions: 49
Troubleshooting 50
All oxygen applications 50
Specifications and Disclaimer 53
Specifications: 53
Disclaimer 54
Index Error! Bookmark not defined.

AMI Analyzer Manual Preface •
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Preface
The AMI story
The AMI series of analyzers pro ide the latest in high-definition oxygen analysis. The series includes trace
(ppm) and percent models in se eral configurations. All of them share the same basic design approach,
using AMI-manufactured oxygen sensors and ad anced high definition electronics for noise and interference
free performance. Se eral aspects of the design are the subject of patents, number 5,728,289 and
6,675,629; the sensors are also co ered by a patent, number 7,316,768.
Please erify that the analyzer was not damaged in transit. If so please contact the shipper as well as AMI.
Caution
Read and understand this manual fully before attempting to use the instrument. In particular understand
the hazards associated with using flammable or poisonous gases.
Address
Ad anced Micro Instruments
225 Paularino Avenue
Costa Mesa, CA 92626
[phone]
www.amio2.com
Last Revised: 07/19/2019

AMI Analyzer Manual Model 201RSP Oxygen Analyzer •
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Model 201RSP Oxygen Analyzer
Introduction
The Ad anced Micro Instrument Oxygen Analyzer Model 201R Series pro ides the latest in high precision
oxygen measurement. It is designed for monitoring oxygen in trace (ppm) ranges in a non-hazardous area.
This manual is di ided into two major sections: a quick reference section for experienced users, and a
detailed exploration of all the many features of the analyzer for all users.
This manual co ers software ersion 5.22.
Features:
•Compact size
•Unique patented cell block
•Auto-ranging display with user-selectable
output range
•Three customer-selected le els of security
access settable ia the RS232 interface.
•Front panel sensor access
•Optional air or span gas calibration, no zero
gases required
•Virtually unaffected by hydrocarbons or other
oxidizable gases
•High accuracy and fast response
•H2S resistant sensor up to 10ppm H2S
•Optional 500ppm H2S resistant sensor
a ailable
•Large liquid crystal display
•Bi-directional serial output with simple
protocol
•Backed by a two year warranty (excluding
sensor)
•Standard isolated 4-20mA output
•Two fully adjustable alarm relay contact
closures 24VDC/230VAC 5A.
•User selectable alarm delay-on acti ation
•User selectable pulse dri ers for latching-type
solenoid al es
•Built-in data logging with real time clock
•Sample system for ambient pressure samples
•Includes high-quality pump
•Span solenoid al e
•Built-in data logging with real time clock
•Logs oxygen, temperature, power supply
oltages
•Logs o er-range spikes
•Automatic logging of low power, start up and
calibration e ents
•USB connection for AMI pro ided software
•RS485 connection for ModBus™
•90-240VAC operation

AMI Analyzer Manual Model 201RSP Oxygen Analyzer •
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Oxygen sensor:
AMI manufactures its own electrochemical sensor. This measures the concentration of oxygen in a gas
stream, using an oxygen specific chemistry. It generates an output current in proportion to the amount of
oxygen present, and has zero output in the absence of oxygen, thus a oiding any requirement to zero the
analyzer. The cell is linear throughout its range. The span calibration may be performed using standard
span gases or ambient air. Unlike competiti e sensors, the AMI sensor is made using a high capacity metallic
body that pro ides long life with about twice the acti e ingredients of con entional sensors.
Sensor Warranty:
The sensor is warranted to operate for a period determined by its class. If the sensor ceases to operate
correctly before this time has elapsed, contact AMI for a return authorization for e aluation. If there is any
e idence of defecti e material or workmanship the sensor will be replaced free of charge.
NOTE: Any e idence of abuse or physical damage, such as a torn membrane, will oid the warranty.
Instrument Warranty:
Any failure of material or workmanship will be repaired free of charge for a period of two years from the
original purchase (shipping date) of the instrument. AMI will also pay for one way shipment (back to the
user).
This warranty does not co er the sensor, which is co ered by its own warranty (see abo e).
Any indication of abuse or tampering will oid the warranty.
Receiving the analyzer
When you recei e the instrument, check the package for e idence of damage and if any is found, contact the
shipper.

AMI Analyzer Manual Important: •
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Important:
This section contains important information to do with safety and installation. Please don’t skip it!
-------------------------Points to consider first! ------------------------------
Environment – what is the temperature range going to be where the analyzer will be installed? If the
temperature is going to go below freezing, you will need a heated ersion or to place it in a temperature
controlled building. Also, make sure it won’t get too hot in the summer – you may need to entilate or e en
air condition a building. The standard (non-heated) temperature specification is 25ºF to 115°F.
Sample conditions – if your sample is hot and wet, you will need to keep water from condensing in the
sample line or analyzer. Contact AMI for ad ice. If the sample contains high amounts of CO2, it will be
necessary to temperature control the analyzer so that the sensor doesn’t explode like a can of soda on your
car’s dashboard in summer. Contact AMI for this one too.
Sample pressure – this analyzer is designed to work with ambient pressure samples, such as that from a
glo e box. As a result it draw the sample from the source through the sample line and then onto the sensor.
The pressure drop across this line must be minimal – 1psig at the absolute most. If the line is long, use 3/8”
or wider tubing.
Power supply – The unit contains a switching power supply that is insensiti e to AC oltage or frequency
changes o er a wide range. It will work with any normal UPS system if desired.
Electrical connections - Following best electrical practices, run the analog output connections separately
from the power and alarm connections. Modbus communications if used should be run with the analog
output wiring, using twisted pair wires for both circuits. Run the alarm wires in the same conduit as the
power wires.
Solenoid valves – if the analyzer is going to be used to control gas flow (such as to shut in contaminated gas)
using solenoid al es, consider using latching type al es and the analyzer pulse feature so as to minimize
power consumption, particularly if you are using a battery and in erter as the power supply. Standard
solenoid al es require power to remain open (or closed), whereas latching al es require power only when
changing their position. This conser es a lot of power.
Span gas –It is strongly suggested that you use room air to calibrate this unit. If you are going to use span
gas to calibrate the analyzer as opposed to air, you will need to plumb a span gas tank to the span inlet on
the back of the analyzer. When you do this, the line to the tank will be full of air. When you subsequently
span the analyzer, oxygen from the air will ha e leaked into the span line potentially increasing its oxygen
content. Wait until the reading has stabilized, and then adjust the span.

AMI Analyzer Manual Important: •
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In addition, since the analyzer includes a pump, you have to take care that you do not pressurize the
sensor with the span gas. It will be necessary to use a bypass valve and flow meter on the span inlet of
the analyzer.

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Installation and Operation
Receiving the analyzer
When you recei e the instrument, check the package for e idence of damage and if any is found, contact the
shipper.
Installation.
Location:
The unit is designed to be mounted in a panel in a general purpose area. It should be mounted at a suitable
iewing le el. Refer to the drawing (figure 1) showing the analyzer dimensions. It is not suitable for use in a
hazardous area.
Although the unit is RFI protected, do not to mount it close to sources of electrical interference such as large
transformers, motor start contactors, relays etc. Also a oid subjecting it to excessi e ibration – anything
worse than a truck may be problematical.

AMI Analyzer Manual Installation and Operation •
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Figure 1. Outline and Cut Out Drawing
8.60
3.005.05
9.00
7.92
4.81
Ø0.21
X 4
Analyzer case outline (dashed) Cut out Front panel outline

AMI Analyzer Manual Short-form Installation Procedure •
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Short-form Installation Procedure
1. Mount analyzer at a con enient eye le el.
2. Deal with any potential condensation or liquid contamination issues.
3. Connect the sample line to the sample inlet port with ¼” tubing, either metal or a high quality plastic
line. Don’t use silicone tubing!.
4. Pressurize the sample line to between 1psig and 10psig).
5. Leak check e ery fitting and weld from the analyzer inlet to the sample tap.
6. Remo e the pressure source from the sample line.
7. Connect ent line to outside or a suitable purge system, or back into the source if appropriate.
8. If using a span gas, connect it to the span port on the back of the analyzer. Include a bypass flow
meter! See step 26 below.
9. Connect power, relay contacts, analog output and RS485 if desired. If using conduit, run the power
and alarms in one conduit, and the analog output and RS485 in the other.
10. Turn on the analyzer with the switch on the power entry module on the back panel.
11. Adjust the sample flow to approximately 1 SCFH with the Flow control al e.
12. Allow the sample gas to purge the unit for a few minutes. Make sure the cell cap is in place.
13. If you are not using the ad anced features, set up the alarms and the output range from the front
panel of the analyzer.
14. Optional:
a. Connect the laptop, run the User Interface ersion III and erify all alarm, output and
security settings.
b. Set the analyzer clock time, and click on “Clear Data Log”.
c. Verify the output calibration .
i. Connect the analog output terminals to an appropriate measuring de ice – preferably the
monitoring de ice you are going to be using with this analyzer.
ii. Arrange that you can readily see the reading gi en by this de ice.
iii. On the AMI User Interface, check the “Zero” check box under SETUP in the ANALYZER
SETUP section.
iv. Obser e the response of the monitoring de ice, and adjust the number in the Zero box until
the monitoring de ice shows what it considers to be zero (which should correspond with
4mA).
v. Check the box marked “Full Scale” in the SETUP section, and adjust the number in the box
next to it until the monitoring de ice shows full scale. This corresponds to 20mA.
vi. Check the “Mid Range” box and erify that the monitoring de ice shows mid scale.

AMI Analyzer Manual Short-form Installation Procedure •
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ii. Uncheck any boxes (if you forget, the analyzer will re ert to its ordinary operation in ten
minutes anyway).
15. Test the entire system, including anything controlled by the alarms or analog output, using a cell
simulator (this is an optional de ice pro ided by AMI).
16. If not using span gas, press and hold the SPAN button on the front of the analyzer for 5 seconds until
the LED turns blue. This will stop the sample flow.
17. Unscrew the cell cap, and install the oxygen sensor.
18. Remo e the shorting tab on the sensor.
19. Optional: in the User Interface ( ersion III) press the “NEW SENSOR” button, and record the sensor
serial number.
20. If not using span gas, Stabilize for 45 seconds ONLY, adjust span to 20.9%. If it already shows 20.9%,
press the UP arrow for a moment anyway (to tell the unit to switch back to sample gas).
21. If using span gas for calibration, stabilize the sensor by allowing sample (or zero) gas to flow at about
1 SCFH.
22. Replace the Cell cap and tighten it down (hand tight).
23. (If you are finished with setting it up) remo e the USB connection cable.
24. If desired, span with known calibration gas.
a) Connect a regulator to span gas tank.
b) Shut off the regulator outlet al e and leak check all the tank fittings, gauges and packing glands
with Snoop or equi alent liquid leak detector (not spray).
c) Connect a bypass flow meter and a series al e at the inlet of the span fitting. The analyzer’s
pump will suck a sample out of this line, and you want the inlet pressure to be atmospheric. You
can control the bypass flow with the al e while the analyzer is drawing its sample.
d) Flow calibration gas WHILE you are connecting the tubing to the span gas fitting. Allow the gas
to purge through the fitting for about 20 seconds before you tighten it.
e) Tighten fitting on the span gas inlet.
f) Press the ALARM HOLD OFF button, and adjust the time displayed to a suitable alue (typically
10 minutes).
g) Press and hold the SPAN button for 5 seconds until the LED turns blue.
h) Allow to stabilize for 2-5 minutes.
i) Verify that the analyzer reads within about 15% of the span gas alue.
j) If so, adjust the analyzer span (see below) until it reads the span gas alue.
k) Let it go back to normal operation (the “SPAN” flag goes out on the LCD display and the LED
turns green), then press the UP arrow and note the number displayed (the “Calibration factor).
l) Turn off the al e on the span gas tank (so it doesn’t all leak out).
If the span gas reads worse than 15% wrong, something is wrong either with the gas, or with the plumbing
(you ha e a leak) or some other error. See the troubleshooting section for some ideas about curing this.

AMI Analyzer Manual Short-form Installation Procedure •
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Laptop set up procedure:
1. Make sure the laptop has the FTDI dri er installed.
a. Windows 7 will probably find the dri er by itself, but XP probably won’t.
b. Run the program called CDM20824_Setup.exe which is either in the AMI CD, or can be
downloaded from the FTDIchips.com site.
2. Install the AMI program if you ha en’t done so already.
3. Run the program.
4. On the User Interface screen, at the top, click the “Port” button. Note the ports listed.
5. Make sure the analyzer is powered up, and connect the USB cable to it.
a. If you connect the cable without power to the analyzer, the port won’t appear.
6. On the User Interface screen, at the top, click the “Port” button again, and you should see an
additional port. Select this port.
7. Let the program figure out how to talk to the analyzer, and watch it load up all the boxes with
numbers or words.
8. If you want to name the analyzer, click on the “User ID:” box. A dialog box will come up, asking for a
password. Use “AMI” (in capitals) as the password, and then write in up to 12 characters as a name
for the analyzer.
9. Set up the output range, that is the range used by the analog output and the alarms to scale the
output for your monitoring de ice.
10. Make sure the security settings are the way you want them.
11. Go through the analog output calibration procedure if desired.
12. Set up the alarms to work as you desire – see the alarm section below for details.
13. If you are installing the sensor, click on the New Sensor button and write in the serial number.
14. Check the analyzer date and time is correct (we set it up for Pacific Standard time, which may not be
correct for you). You can send the computer time to the analyzer by clicking the Set Analyzer Time
button.
15. Clear the stored data by clicking the “Clear Data” button in the DATALOG section on the right.
The following sections describe each of the abo e sections in more detail.

AMI Analyzer Manual Expanded Installation Procedure •
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Expanded Installation Procedure
Figure . The 01RSP
This section follows the format of the installation procedure abo e but with greatly expanded explanations
and co erage of detail issues.
1. Mount analyzer at a convenient eye level.
The basic analyzer is designed for operation between 25ºF and 115ºF. It is a ailable with a heater, but this is
intended only to stabilize its temperature if it to be measuring in pure CO2. The gas connections are made
on the left side of the back of the analyzer, while the electrical connections are at the bottom of the back
The analyzer is intended to be mounted on a panel in a building.

AMI Analyzer Manual Expanded Installation Procedure •
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If the analyzer is mounted in a building with other equipment, make sure it won’t get too hot during the
summer. The sensor will rapidly die in temperatures higher than 115ºF. You may need to install entilation
or e en air conditioning.
2. Deal with any potential condensation or liquid contamination issues.
If the sample may contain condensable liquids, they must be pre ented from entering the analyzer. This
analyzer is intended to work with clean dry samples only.
3. Connect the sample line with ¼” tubing.
Use a high quality tubing only to connect the sample to the analyzer. Most plastic tubing will be OK but do
not use silicone tubing – the soft, easy to use stuff. It is remarkably permeable to oxygen and will gi e you
incorrect readings. Normally ¼” tubing is adequate unless the sample run is ery long and the source
pressure low – in this case you may ha e to use wider tubing.
The analyzer contains three solenoid al es that control the gas flow. When turned off, the sensor is sealed
off from the inlet and the exhaust. As soon as power is applied, the exhaust al e and the sample al e
open. You can close the sample al e and open the span al e by pressing and holding the span button for
fi e seconds. If you then touch either the up or down button, the analyzer will close the span al e and open
the sample al e after another few seconds. Don’t use the metering al e to shut off the flow (as it is a fine
adjustment al e)!
4. Pressurize the sample line to line pressure (1 – 10psig).
The exact pressure doesn’t matter – we want enough so that you can easily see leaks in the following step.
5. Leak check every fitting and weld from the analyzer inlet to the sample tap.
Use a liquid soap solution such as “Snoop™” or similar. Don’t spray it on! You are looking for little bubbles
that appear after a while, indicating a leak. E en the tiniest leak will allow oxygen to enter the gas stream,
no matter what the pressure inside the line is. Check absolutely e ery possible source including welds, al e
packing, fittings both around the tube and the nut, and anything else that might leak.
. Connect the vent line to outside or a suitable scavenging system, or if appropriate back to the
source.
It is important that you neither back-pressurize the sensor by restricting the exhaust flow, or that you pull a
acuum on it by directly connecting it up to a sca enging system. If you are measuring an inert gas, it is
normally acceptable to ent the gas into the room (as long as you ha e some kind of entilation!). If it is a
flammable or otherwise hazardous gas, use a sca enging system that draws in room air along with the
exhaust from the analyzer (putting an exhaust tube a foot or so up into a wider sca enging pipe works well).
Allow the sca enging system to draw in room air along with the exhaust.
If using the analyzer with a glo e box or similar de ice, it is often appropriate to return the sample to the
source. Bear in mind that you might not want to do this if you intend to calibrate with air!

AMI Analyzer Manual Expanded Installation Procedure •
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7. Adjust the sample flow to approximately 1 SCFH with the Flow control valve located on the front
panel.
The Flow Control Val e is the metering al e on the right of the front panel. It is a sensiti e needle al e –
so don’t try to use it to shut off the flow. Use the solenoid al es for this.
The exact flow rate is not important – 1 SCFH is half way up the flow meter, so is easy to see. You want the
flow between about 0.5 SCFH and 2 SCFH at the maximum. Lower flows will result in longer response times,
and possibly higher oxygen readings as minor leaks aren’t diluted as much by the flow. Higher flow rates
will tend to increase the pressure on the sensor which will increase the oxygen reading.
Figure 3. The 01RSP back panel
8. Connect power, relay contacts, analog output and RS485 if desired. If using conduit, run the
power and alarms in one conduit, and the analog output and RS485 in the other.
The AC power uses a standard IEC connector like any desktop computer. Although the power entry module
allows you to select the AC oltage, it is not necessary to do so as the switching power supply used has a
ery wide input range, and can handle oltages from 90 to 240VAC, and 50 and 60 Hz supplies.
The analog output – 4-20mA – is connected to the “+” and “-“ symbols. This signal is isolated from ground.
If the de ice to which you are connecting is also isolated from ground, make sure you ground the “-“
connection at the analyzer. The terminal marked by the ground symbol may be used for this purpose, in

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which case the output is no longer isolated. DO NOT GROUND BOTH ENDS! If you do so, you will generate a
ground loop which will seriously upset the readings. Normally you would use the ground terminal for a
shield. It is possible to use the AMI User Interface program on a laptop to calibrate the 4-20mA output to
your monitoring de ice.
The two terminals marked A and B are for the RS-485 ModBus connection. This is not isolated from ground.
There are two alarm contacts. These are form C contacts. The NO and NC markings refer to the connections
when the relay is unpowered. If the alarms are operated in “Failsafe” mode, the NC contact will be
connected to the C contact either when the analyzer is in alarm or when power is remo ed.
Run the power and alarm wires through one conduit, and the analog output and RS485 lines through the
other.
9. Power up analyzer.
When you do so, the LCD should light up in the right side enclosure, and the Status LED on the front panel
should turn green. The solenoid al es will open allowing the sample to run through the analyzer. If the cell
cap is not on it, you won’t see any flow through the flow meter as all the flow will exhaust from the cell
pocket in the front.
10. If you are not using the advanced features, set up the alarms and the output range from the front
panel of the analyzer.
First choose the output range. This is the oxygen range that the analog output and alarms respond to. For
example, if you use a range of 10% full scale, 20mA corresponds to 10%, and 4mA corresponds to zero. Use
a range that gi es you enough resolution to see normal beha ior, but allows you to ha e reasonable alarm
set points.
Set the range by pressing the OUTPUT RANGE button, and then scroll the number on the screen with the UP
and DOWN arrows until it says what you want.
When you ha e set the output range, set the alarms. The alarm set point is shown as a ppm (or percentage)
alue, but it is internally stored as a percentage of the output range you just chose. If you change the range,
the alarm set points will change along with it.
Note that this range has nothing to do with the measurement range of the analyzer. The analyzer LCD
automatically scales its reading from 0.1% to 25%; it’s only the analog output that gets scaled by the range,
not the measurement.
If you want to set up other alarm features, such as whether the alarms latch or open or close on alarm, you
ha e to use the laptop user interface program.

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11. Optional:
This section talks about using the laptop to make more ad anced choices.
Figure 4. User interface initial screen
a. Connect the laptop, run the User Interface version III and verify all alarm, output and
security settings.
Please see the chapter below about using the user interface for the details of this.
Note that you must ha e power on the analyzer before the laptop can find the communication port! Plug in
a standard USB cable (such as the kind often used to connect a PC to a printer) to the port in the middle of
the back of the analyzer. Select the comm port at the top of the screen, and click Open COMM. The
program will figure out how to communicate to the analyzer, and fill in all the boxes once it connects.
b. Set the analyzer clock time, and click on “Clear Data Log”.
The analyzer stores its readings for about two weeks for you to look at subsequently. It may ha e some
readings stored from the check-out process, and these might confuse you when you subsequently iew
them. Also, we set it up on PST, and your time zone may be different. So set the time, and clear the data. In
due course, click on the Download Data button to see the stored data.

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c. Verify the output calibration.
You should only need to do this if your flow computer or similar monitoring de ice has an uncalibrated
input.
i. Connect the analog output terminals to an appropriate measuring device – preferably
the flow computer or similar monitoring device you are going to be using with this
analyzer.
You can simply use a multi meter connected to the output terminals. If so, make sure it is set correctly –
don’t use a oltmeter to measure current! Often people lea e their meter in the current measurement
position and the next time they measure a oltage they blow the current fuse. If this has happened, the
meter won’t measure current until you replace it.
ii. Arrange that you can readily see the reading given by this device.
iii. On the AMI User Interface, check the “Zero” check box under SETUP in the ANALYZER
SETUP section.
iv. Observe the response of the monitoring device, and adjust the number in the box next
to the Zero label until the monitoring device shows what it considers to be zero (which
should correspond with 4mA).
v. Check the box marked “Full Scale” in the SETUP section, and adjust the number in the
box next to it until the monitoring device shows full scale. This corresponds to 20mA.
vi. Check the “Mid Range” box and verify that the monitoring device shows mid scale.
vii. Uncheck any checked box (if you forget, the analyzer will revert to its ordinary operation
in ten minutes anyway).
12. Test the entire system, including anything controlled by the alarms or analog output, using a cell
simulator.
As an option, AMI can pro ide a “Cell Simulator” that mimics the operation of a sensor between 0-100ppm,
so that you can erify that your control system or flow computer correctly reads the analyzer’s output and
responds correctly to the alarm contacts.
13. Turn off the sample flow by closing the needle valve all the way
You don’t want to dilute the air under the sensor when you first place it in the analyzer. Don’t tighten the
needle al e or you will damage it – just turn it down until it stops.
14. Unscrew the cell cap, and install the oxygen sensor.
Unscrew the cap first. Open the sensor bag, remo e the sensor by holding the little handle and immediately
put it into the cell compartment, gold side up, and with the little metal tag on the side facing you. When it is
in place, hold the sensor in place and pull out the tag. Do it in this order so that the sensor is always
operating, eating up oxygen that gets in through its membrane. The length of time you take o er this is
critical in determining how long the sensor takes to get down to a low range.
Bear in mind that if you ha e returned the sample to the source, you will be flowing air into the source while
you do this. You may want to temporarily exhaust the sample to room air, and connect it to the source
when you are done with this procedure.