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AMI Analyzer Manual 

Installation Procedure  

  12 

Alarm Bypass 

Press the alarm bypass button prior to calibration if you have the alarms attached to 

anything, so as to stop them from going off when the analyzer sees the high oxygen level 

in the calibration gas.  You can adjust the bypass time when you press that button – it 

shows what the bypass time is, and you can change it with the UP or DOWN buttons as 

desired.  The analog output will also be held constant during this time. 

Span problems 

Sometimes you will run into problems.  If the sensor is old, it may not be able to come up 

to the span gas level.  If so, you need a new sensor.  Sometimes sensor will calibrate on 

span gas but will fail on air.  This also indicates an old sensor.  You can see the sensor 

state by pressing the UP button when the sensor is showing the oxygen level – it displays 

the “Span factor”, a number between about 450 and 1000.  As the sensor gets old each 

calibration will increase this number and when it gets up to about 850 it is time to 

replace the sensor. 

Sometimes the sensor won’t calibrate on span gas properly, but since it is a new sensor 

you figure something must be wrong.  If something like this is happening, perform an air 

calibration and allow the sensor to come back down to a low reading on the sample.  

Then perform a span gas calibration only don’t adjust the span factor with the UP or 

DOWN buttons, and see what the analyzer says the gas contains.  If the gas value isn’t 

what you think it should be, it is the gas that is wrong, not the analyzer, because that air 

calibration is in fact very valid.  You will have to trouble shoot whatever has happened 

with your gas. 

Output range concept: 

The analyzer displays the oxygen level in appropriate units on the LCD, automatically 

adjusting its sensitivity as required.  Meanwhile the analog output and the alarms are set 

on a single (user selectable) “Output” range. 
For example, you can set the analog output to correspond to 0-100ppm, and the alarms 

to be say  40ppm and 50ppm (i.e. 40% and 50% of range), activating above set point.  If 

the oxygen level actually is 25ppm, the display will show 25.0ppm, and the output signal 

will be at 25% of full scale.  If the oxygen level becomes 200ppm, the display will show 

200ppm, but the 4-20mA output will be saturated, and the alarms will both be activated. 
If you now manually change the output range to 0-1000ppm, the reading will stay at 

200ppm, the 4-20mAoutput will go to 20% of scale, and the alarms will de-activate, since 

they now correspond to 400ppm and 500ppm, i.e. still 40% and 50% of range.   

Front Panel Controls: 

 

The controls all work the same way.  You press the function you want for a second, and 

let go, and the display will show the value corresponding to that function, for about 3 

seconds.  For example, if you press the OUTPUT RANGE button for a second, the display 

will show the full scale output range.  You can change this value (if the security setting 

allows) by then pressing the UP or DOWN arrow button within about three seconds.  You 

can either press this once for a small change, or you can hold it down, in which case the 

number will change slowly at first, and then faster.  If you overshoot your target, press 

the other button to go back, and the display will again start moving slowly.  If you release 

Summary of Contents for 2001LC

Page 1: ...AMI Oxygen Analyzer Manual Model 2001LC AMI Costa Mesa CA ...

Page 2: ...ion and Operation 4 Receiving the analyzer 4 Installation 4 Location 4 Precaution 4 Installation Procedure 5 Connect gas and power lines 7 Interconnections 8 Alarm connections 8 Output connections 8 Serial connections 8 Sample Handling 9 Operation 10 Analyzer operation 10 Sample tubing and components 10 Leaks 10 Exhaust 10 Calibrating the analyzer 11 Output range concept 12 Front Panel Controls 12...

Page 3: ...Bypass 14 Verify Span Factor 14 Read the Temperature 14 Alarm Functionality 14 Maintenance and troubleshooting 15 Maintenance 15 Periodic Calibration 15 Sensor Replacement 15 Sensor replacement cautions 16 Sensor replacement procedure 17 Bleeding a regulator 18 Troubleshooting 19 All oxygen applications 19 Specifications and Disclaimer 21 Specifications 21 Disclaimer 22 ...

Page 4: ...the air contains 20 9 209 000ppm of oxygen and it can get into a pressurized pipeline through the smallest leaks Oxygen molecules will enter through a leak no matter the pressure or the nature of the gas in the line This analyzer is an exceptionally sensitive leak detector including those provided by improper installation Make sure you read this manual carefully prior to installation Caution Read ...

Page 5: ...us area This manual covers software version 1 0 Features Compact size Unique patented cell block Auto ranging display with user selectable output range 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 Large liquid crystal display Backed by a two year warranty excludin...

Page 6: ...h much faster come down times typically under twenty minutes to 10ppm from a 1 minute air exposure 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 evaluation If there is any evidence of defective material or workmanship the sensor will be replace...

Page 7: ...panel in a general purpose area It should be mounted at a suitable viewing level Refer to the drawing figure 1 showing the analyzer dimensions It is not suitable for use in a hazardous area or with flammable gases 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 avoid subjecting it to...

Page 8: ... 3 Deal with any potential condensation or liquid contamination issues 4 Connect the sample line to the sample inlet port with ss tubing 5 Pressurize the sample line to line pressure between 1psig and 20psig 6 Leak check every fitting and weld from the analyzer inlet to the sample tap 7 Connect vent line to outside or a suitable purge system 8 Connect power relay contacts and analog output If usin...

Page 9: ... spray e Disconnect the sample tubing from the inlet port either by physically removing it or by using an external three way valve f Flow calibration gas WHILE you are connecting the span gas tubing to the inlet fitting or the selection gas valve port Allow the gas to purge through the fitting for about 20 seconds before you tighten it g Press the ALARM BYPASS button and adjust the time displayed ...

Page 10: ...to a suitable vent Sample gas The sample gas inlet pressure should be between 1 40psig Span gas Span gas if desired must be provided by a user supplied valve Exhaust The exhaust line may be left open or vented to a suitable vent If used with a scavenging system use a large diameter pipe for example pipe as the input to the scavenging system and allow the vent to terminate a little way inside this ...

Page 11: ...By failsafe is meant that the relays are powered when NOT in alarm so that if power fails they indicate an alarm condition The contacts can handle AC or DC voltages and can carry up to 5A of current for a resistive load Inductive loads such as solenoid valves should be snubbed we suggest that you connect diodes or Zener diodes or Transzorbs directly across them to absorb the inductive spike Do not...

Page 12: ...ure within this range Higher pressure applications or varying pressure applications will need a regulator to control pressure The analyzer is not sensitive to flow changes between about 0 2SCFH and 5 SCFH but it is sensitive to back pressure changes changes in exhaust pressure The flowmeter is mounted on the exhaust so that the oxygen reading is not affected by potential leaks around the flowmeter...

Page 13: ... through its O rings The span gas pressure should also be held below 100psig If you permanently connect a span gas tank to it via a user supplied three way valve make very sure that the connection is leak tight as otherwise not only will the calibration be in error but also you will lose all of your span gas as it leaks out Leaks If you suspect a leak due to high oxygen readings change the flow ra...

Page 14: ...will contaminate the gas in the tank Connect the regulator to the analyzer with a stainless steel line and leak check the connection with Snoop or similar leak detection fluid Purge the line for several minutes with a small flow of gas prior to doing this and leave the gas flowing while you make the connection to the analyzer This prevents a slug of air from giving you excessively high readings wh...

Page 15: ...ecause that air calibration is in fact very valid You will have to trouble shoot whatever has happened with your gas Output range concept The analyzer displays the oxygen level in appropriate units on the LCD automatically adjusting its sensitivity as required Meanwhile the analog output and the alarms are set on a single user selectable Output range For example you can set the analog output to co...

Page 16: ...n If the output range does not change the security level must be set to full or span only security In this case change the security level with the laptop and the AMI User Interface program Alarm Set Points The alarm set points can be viewed and changed from the front panel View Alarm Set Points Press either of the ALARM SET POINT buttons and let go The alarm set point will be displayed for about 3...

Page 17: ... up slowly over the life of the sensor When the value has gotten up to 1000 the sensor has reached the end of its life and should be replaced Also if the value suddenly jumps it indicates that the sensor is getting close to the end of its life Read the Temperature Press the DOWN arrow button The display will show the temperature of the cell block in degrees Fahrenheit The value is limited to 25F a...

Page 18: ...bration is usually satisfactory Use in a particularly aggressive environment may degrade the sensor faster in this case calibrate more often Sensor Replacement This should be done based on the Span Factor feature rather than as a response to a dead sensor See the chart below for recommended sensor replacement Sensor Part number Description Expected life T2 4SEN09 1 Trace oxygen CO2 background 9 mo...

Page 19: ... it does immediately flush the affected area with water for a period of at least 15 minutes Refer to the Material Safety Data Sheet provided Dispose of leaking or used sensors in accordance with local regulations Sensors usually contain lead which is toxic and should generally not be thrown into ordinary trash Refer to the MSDS to learn about potential hazards and corrective actions in case of any...

Page 20: ...lly open the bag using a pair of scissors or a knife Make sure you don t cut yourself or stab the sensor In the rare event that the sensor has leaked there will be liquid in the bag If so do not proceed you need a new sensor Be careful that you don t poke anything such as a fingernail through the membrane 8 Don t pull out the shorting tab yet 9 Holding the sensor by its tab membrane side down slid...

Page 21: ... to Bleed the regulator first 1 Install the regulator on the span gas bottle but do not open the bottle valve yet 2 Close the regulator exit valve 3 Close the regulator to what would be no pressure on the outlet 4 Briefly open the bottle valve and close it again 5 Loosen the nut connecting the regulator to the bottle and allow the pressure to bleed off and then tighten it again 6 Open the regulato...

Page 22: ... soap solution or equivalent 4 Verify that the gas flow rate is correct 0 1 to 2 SCFH 5 Oxygen diffusion can be a serious problem Verify that no plastic tubing or other plastic components are used in a trace gas system including diaphragms of pressure regulators packing of valves etc For percent applications similar problems may be experienced with silicone tubing Use Teflon or Tygon or similar hi...

Page 23: ... sensor replacement instructions under Maintenance No voltage or current output to recording device 1 Verify that the output wires are properly stripped and connected 2 Verify the connections on the output terminal block 3 Verify that the output connections are not shorted all the way back to the recording device Disconnect the wires from the analyzer and use an ohmmeter to check for shorts or ope...

Page 24: ...1 psig to 100psig Humidity 95 non condensing Operational conditions Pollution degree 2 Installation category I I Drift 1 of full scale in 4 weeks at constant temperature dependent on sensor Expected cell life 9 months to 2 years Response times 90 of full scale in less than 0 10 ppm 25 sec 0 100 ppm 10 sec 0 1000 ppm 10 sec Output 4 20mA isolated Alarm contacts 230 117VAC 5A or 28VDC 5A resistive P...

Page 25: ...s or associated components AMI s obligation is expressly limited to the analyzer itself The AMI analyzer is not designed as a primary safety device that is to say it is not to be used as the primary means of assuring personnel safety In particular it is not designed to act as a medical instrument monitoring breathing air for correct oxygen concentration and should not be used as such when it is th...

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