Sensotec Rapidox 1100ZR3-H-PFC Instruction Manual

Rapidox 1100ZR3-H-PFC

Oxygen Analyser

(Heller Version)

Instruction Manual

Revision 1.2

Cambridge Sensotec Limited

Unit 29 Stephenson Road

St Ives

CAMBS

PE27 3WJ

Tel. [phone]

Fax [phone]

Mobile [phone]

[e-mail]

Cambridge Sensotec Rapidox 1100ZR3-H-PFC O2 Analyser Instruction Manual

Declaration of Conformity

Manufacturer: Cambridge Sensotec Ltd.

Unit 29 Stephenson Road
St Ives
Cambs
PE27 3WJ

Product Names: Rapidox portable oxygen gas analyser

Model Numbers: RX1100ZR3-H-PFC

Conform to the following specifications:

EMC: EN 61326:2006 Electrical equipment for measurement,

control and laboratory use

Declaration: I declare that the above products conform to the applicable

requirements of the LVD Directive 2006/95/EC and the EMC Directive 2004/108/EC
and is CE marked accordingly.

Signature:

Name: Dr. Mark Swetnam

Title: Managing Director

Company: Cambridge Sensotec Limited

Date: 16th December 2013

WEEE Regulations 2006

Cambridge Sensotec takes its responsibilities under the WEEE
Regulations extremely seriously and has taken steps to be compliant in
line with our corporate and social responsibilities. In the UK,
Cambridge Sensotec has joined a registered compliance scheme
“WeeeCare” (WeeeCare registration number WEE/MP3538PZ/SCH).

UK users only: If you have purchased any electronic or electrical product from
Cambridge Sensotec since 2007 and would like to dispose of it correctly under the
WEEE scheme, please contact us and we will be happy to either arrange the
collection of the waste or have it returned to our offices for recycling. All our in­house manufactured products are scheme compliant and carry the WEEE label
indicating that it is NOT allowed to be disposed of in a landfill site.

Cambridge Sensotec Rapidox 1100ZR3-H-PFC O2 Analyser Instruction Manual

Contents

1. Introduction .......................................................................................................... 1

2. Features ................................................................................................................. 1

3. Heller Specific Features ........................................................................................ 2

4. Technical Specification ........................................................................................ 3

5. Precautions ............................................................................................................ 4

6. Warning ................................................................................................................. 4

7. Rapidox Operating Instructions ........................................................................... 4

7.1 PFC Connections ........................................................................................... 5

7.2 The Rapidox Analyser - Menu System ......................................................... 6

7.3 Getting Started ............................................................................................... 6

7.4 Display Behaviour ......................................................................................... 6

7.5 Pump Control ................................................................................................. 7

7.6 Menu Access / Passwords ............................................................................. 7

7.7 Rapidox Calibration ....................................................................................... 8

7.8 Programming the Multiplex ........................................................................ 10

7.9 Cleaning the Sensor ..................................................................................... 11

7.10 Alarms .......................................................................................................... 12

7.11 Analogue Outputs ........................................................................................ 13

7.12 Setting the Display Units ............................................................................ 17

7.13 Setting the Display Options ........................................................................ 17

7.14 Pressure Correction Mode ........................................................................... 18

7.15 Setting the Baud Rate .................................................................................. 18

7.16 RS232 / RS485 Port ...................................................................................... 19

7.16.1 RS232 Protocol ..................................................................................... 19

7.16.2 RS485 protocol ..................................................................................... 21

7.17 Printing ......................................................................................................... 21

7.18 Load Defaults ............................................................................................... 22

8. Rapidox Software Instructions ........................................................................... 23

8.1 Software Installation ................................................................................... 23

8.2 Getting Started ............................................................................................. 23

8.3 On-Screen Help ........................................................................................... 24

8.4 Configuration Page ...................................................................................... 24

8.5 Reconfiguring the Analyser ........................................................................ 25

8.5.1 Config 1 Screen ........................................................................................ 26

8.5.2 Config 2 Screen ........................................................................................ 27

8.5.3 Alarm Config Screen ................................................................................ 28

8.6 On-Screen LCD ............................................................................................ 29

8.7 Remote Calibrating and Cleaning ............................................................... 30

8.8 Calibration Error Messages ......................................................................... 31

8.9 Software Utilities ......................................................................................... 32

8.10 Setting Analyser Date and Time ................................................................. 33

8.11 Log Diagnostics For ..................................................................................... 33

8.12 Show / Hide LCD ......................................................................................... 33

8.13 Image Grabber .............................................................................................. 33

9. Data-Logging Software ........................................................................................ 34

Cambridge Sensotec Rapidox 1100ZR3-H-PFC O2 Analyser Instruction Manual

9.1 Introduction ................................................................................................. 34

9.2 Auto-Log Feature ......................................................................................... 34

9.3 Setting up the Data Logger .......................................................................... 34

9.4 Running the Data Logger ............................................................................. 36

9.5 Auto Date Stamped Files ............................................................................. 36

9.6 Live Time Graphing Screen ........................................................................ 37

9.7 Main Graph Window ................................................................................... 38

9.8 Plot Colours.................................................................................................. 38

9.9 Graph Titles and Labels .............................................................................. 39

9.10 Plot Co-ordinates ......................................................................................... 39

9.11 Last data point ............................................................................................. 39

9.12 Using the Cursor .......................................................................................... 39

9.13 Zooming ....................................................................................................... 40

9.14 Y-Axis Graph Units ..................................................................................... 40

9.15 Oxygen Scale ............................................................................................... 40

9.16 Second Y Axis .............................................................................................. 40

9.17 Loading an Old Run .................................................................................... 40

9.18 Printing Graphs ............................................................................................ 41

9.19 Data Logging in the Background ................................................................. 41

9.20 Pausing the Data Logging ............................................................................ 41

9.21 Changing the Data Logging Parameters Mid-run ....................................... 41

9.22 Working with Spreadsheets ........................................................................ 41

9.23 Disaster Recovery ........................................................................................ 42

9.24 DDE Protocols .............................................................................................. 42

10. Troubleshooting .............................................................................................. 44

10.1 Warranty ...................................................................................................... 45

10.2 Conditions of Warranty: .............................................................................. 45

11. Appendix 1: Proportional Flow Control ........................................................ 47

11.1 Connections ................................................................................................. 48

11.2 Software Description ................................................................................... 48

11.3 Prop. Flow Control tab ................................................................................ 49

11.4 SW Alarm Config tab ................................................................................... 52

11.5 Data-logging with PFC ................................................................................. 53

Cambridge Sensotec Rapidox 1100ZR3-H-PFC O2 Analyser Instruction Manual

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1. Introduction

The Rapidox 1100ZR3-H-PFC (Z=zirconia sensor R=rear panel gas input 3=three
channel multiplexer H=Heller version PFC = Proportional Flow Control) oxygen
analyser allows fast and accurate oxygen analysis over the oxygen range 1ppm to
100% O2. The analyser provides continuous on-line oxygen analysis, with a
typical response time of less than 4 seconds for a 90% response to a step change in
gas compositions.

The Rapidox 1100ZR3-H-PFC is a fully integral unit complete with a powerful
diaphragm pump to provide variable gas sampling up to approximately 1.2 litres
per minute. The analyser has three separate gas inlets that can be independently
programmed to sample gas sequentially OR in various combinations using manual
operation. This is referred to as the multiplex in this manual.

The sensor head is located inside the analyser and comprises a zirconia ceramic
tube that needs to be heated to 650°C before it will conduct oxygen ions. The
analyser supplies heat to the sensor, which is controlled very accurately by a
regulated power supply incorporated in the instrument. An internally mounted
pressure sensor compensates for any fluctuations in pressure or vacuum caused
by differing flow conditions. The sample gas is collected from one or more of the
three gas inputs controlled by a series of electric solenoid valves.

The analyser is packed with features including programmable alarm circuits,
programmable analogue outputs, easy calibration (user selectable gases), RS232
communications and complete communications / data-logging software.

This version of the Rapidox is specially configured with PFC (Proportional Flow
Controller) output that that is programmed using the Rapidox software. See
Appendix 1 for more details.

2. Features

 Multiplex gas analyser with three separate sample gas inlets
 Very fast measurement response (typically 4 seconds for a 90% response).
 Wide measurement range available (1ppm to 100% O

2

).

 Accuracy ± 1% of the actual measured oxygen.
 Easy calibration procedure requiring any two or three gas mixtures (ordinary

room air is usually one).

 Low maintenance, sensor life expectancy typically 17,500 hours
 Powerful variable speed diaphragm pump fitted for sampling the gas

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 Large back-lit LCD display (16 x 2 characters).
 RS232, 0-10V and 4-20mA current loop outputs (both fully programmable).
 Fully programmable alarm circuits.
 Full data-logging software accessed via RS232 connection to a PC (RS485

available on request).

 PIN code protection available
 Optional printer attachment

3. Heller Specific Features

 Internal carbon trap fitted to the sample gas line
 Heller model name on the boot up screen
 Voltage input on rear panel to enable / disable the sample pump
 Modified software
 PFC control loop outputs

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4. Technical Specification

Property

Specification

Supply Voltage

90-260VAC, 50/60Hz

Power consumption

100W (max)

Analyser dimensions

350mm X 263mm X 150mm

Weight

4.0 kg

Display

16

6 play0mmimensions0/60 Hzed con

Warm up time

3-4 minutes at 20°C

Normal operating temperature

5-35°C

Sensor Range

1ppm to 100% O2 taken from three
independent sample inputs.

Sensor Accuracy

±

1% of the actual measured oxygen

content

Outputs: O2 voltage

0-10V (user-programmable) into minimum
5k

O2 current

4-20mA current loop (user-programmable)
into maximum 500

O2 PID control

4-20mA current loop (user-programmable)

into maximum
500



All data and parameters

RS232 or RS485 - data streamed on
demand

Sample Pump

Long-life vacuum pump

Flow Rate

0-1.2 L.min-1

Max. gas temperature on input

60°C

Calibration

Requires 2 or 3 user-selectable gas

compositions (air is default plus another
two)

Table 1: Rapidox 1100ZR3-H-PFC technical specification

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5. Precautions

Make sure you read and understand these instructions and keep them safe for later
use. The unit should not be exposed to extreme temperatures < -5°C or > 60°C.
Normal operating temperature is 5-35°C. Avoid direct sunlight. Do not use liquid
cleaners, aerosols or solvents to clean the case. Use a damp cloth for cleaning. Do
not use this equipment near water. Avoid touching the LCD display as this may
cause permanent damage. Make sure the rear ventilation slots and the fan on the
rear panel are free of obstruction. There are no user serviceable parts in this unit.
Do not attempt to repair yourself. Refer all servicing to qualified Cambridge
Sensotec personnel.

6. Warning

This unit is NOT designed for use in life support situations. No responsibility can
be held for injury or loss of life caused by inappropriate use of this equipment.

7. Rapidox Operating Instructions

Figure 1: Rapidox 1100ZR3-H-PFC front panel. Numbers are referred to in the text.

1

2

5

1

2

5

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Figure 2: Rapidox 1100ZR3-H-PFC rear panel. Numbers are referred to in the text.

7.1 PFC Connections

On the rear of the PFC coded machines are two terminals labelled “PFC Valve 4­20mA” and “Supply Valve (In)”.

Figure 3: Rear Panel Terminal Strip

a) PFC Valve 4-20mA: These connections provide the 4-20mA signal to

control the gas valve. The signal is generated by the PID control loop
parameters entered by the user.

b) Supply Valve (In): This connection requires a 12-24V connection from the

oven to indicate when it is operation. The PFC output and the analyser
sample pump are disabled when there is no voltage signal present.

3

4

6

7

8

9

2

1

+ve

+ve

-ve

-ve

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7.2 The Rapidox Analyser - Menu System

All of the user-programmable functions are accessed via a menu system which is
controlled using the front panel Keypad (2). To access the menu press the ENT
button and to escape and return to the operating screen press ESC at any time.
The menu system flow chart is shown in Appendix 2 below.

7.3 Getting Started

Ensure that the Rapidox analyser is located away from extreme heat and dirt
environments. Plug the unit in to a suitable supply (noting the information on the
serial sticker and using the power cable supplied) using the rear power socket (8).
Make sure that the cooling fan (9) is not obstructed during operation.

Push the gas sample tube (6mm OD/4mm ID) on to any of the three
GAS IN (3) connectors on the multiplex and fit the retaining collar hand tight. If
other sample tubes are to be connected repeat this until all three sample points are
used. Repeat for the GAS OUT (4) connector should an outlet tube be required.
The pump will draw gas at a flow rate depending on the value set either in the
software or from the menu. The default setting is one hundred percent.

Turn the unit on using the red power switch on the front (5). The LCD (1) will
display the firmware version followed by the message “HEATING SENSOR”. The
sensor will take approximately four minutes to come up to temperature, after
which the Rapidox will begin to take measurements. The progress of the sensor
heater is shown in the form of a bar graph on the LCD (1).

Allow thirty minutes for the box to stabilise fully. This allows the components of
the analyser to reach a stable working temperature. During this warm-up period it
is common for the baseline oxygen to drift by a small amount, which may be
corrected by re-calibrating (see section 7.7).

7.4 Display Behaviour

Once at temperature the LCD display will show the oxygen reading (in percent or
ppm) on line 1. The bottom right corner of the LCD shows the three multiplex
inlets as circles “” representing “1,2,3” If a channel is currently being sampled
by the multiplex then this circle goes black e.g. “” to represent channel 1. If
the multiplex is in Manual mode then the word “MAN” alternates on the display
to remind you. See section 7.8 for a full description of the multiplex system. The
symbol AL1 or AL2 may also appear in the bottom right of the LCD if the alarm
system is enabled and an alarm condition applies. The oxygen sensor reading
may flash or show “O/Range” when its limits are reached, and error messages will
be displayed if there is a fault with the sensor. See Table 2 for more details:

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Oxygen Sensor Display Possibilities

O2 Reading > 9999.9%

Display shows “O/Range”

O2 Reading >0.5ppm and < 9999.9%

Display shows the normal oxygen reading in % or ppm

O2 Reading <0.5ppm

Display shows <0.5ppm flashing

O2 Reading is flashing

Indicates that the pressure sensor is out of range and
automatic pressure correction is on.

O2 Sensor takes > 10 minutes to warm up

Display shows “Possible sensor Fault” because the sensor
heater is failing.

O2 Sensor has failed completely or become
disconnected

Display shows “No sensor or sensor Fault”

O2 Sensor is OK but the pressure sensor is faulty and
the auto pressure correction mode is selected

Display shows “Fault” flashing.

Pressure Sensor Possibilities

Pressure Reading is >1000mbar

Display shows “O/Range Press.”

Pressure Reading is >-1000mbar and <1000mbar

Display shows the normal pressure reading in mbar, bar,
kPa, torr or psi

Pressure Reading is <-1000mbar

Display shows “U/Range Press.”

Pressure sensor has failed completely or become
disconnected

Display shows “Fault Press.” With the word “Fault”
flashing

Table 2: Different display possibilities depending on the sensor reading.

7.5 Pump Control

Please note that the pump speed is fixed at 100% on Heller coded machines.

The flow rate of gas drawn into the analyser from the multiplex can be controlled
using the menu option 9: “Set Pump Flow”. The unit is supplied with the flow
rate set to 100% which equates to approximately 1.2 Litres per minute. If you
wish to change the flow rate press ENT and select menu option 10. Use the UP &
DOWN arrows to change the value from OFF – 100% in steps of 10% increments.
When using the unit with a pressurised (flowing) gas source the pump can be left
switched off. Note that on Heller units coded “PFC” the pump will be deactivated
if there is no voltage signal supplied to the supply valve (In) terminals on the rear
panel. Please see section 11.1 for further details.

7.6 Menu Access / Passwords

The analyser has an option to set a password that will restrict access to the menus.
The password menu is disabled by default in the factory. If you wish to password
protect the analyser press ENT and scroll down to the PASSWORD option (Menu
option 12). Pressing ENT again will ask you for the default password which is
“0000”. Enter this using the UP and DOWN arrows. Once the password has been
entered successfully you can chose between ENABLE and DISABLE in the menu
using the UP and DOWN keys.

The other option is to RESET the password to a new value. The password must be
4 digits long and can be any combination of numbers from 0-9. Make sure that the
new password is noted down!

If the password function has been enabled then in the future each time the menu
system is accessed then the password prompt will display. After the correct
password is entered then the full menu will be accessible. You can make as many
changes as you want to the options and only press ESC once you have finished.

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Pressing ESC takes you out of the password protected area and you will have to re­enter the password to go back in again.

If the password has been forgotten please contact Cambridge Sensotec who will
advise you on how to recover it.

7.7 Rapidox Calibration

Please note that when calibrating you must apply calibration gas using Gas 1 input
only. Gas 2 and Gas 3 inputs are disabled in the calibration process to avoid cross
contamination via the multiplex. Disconnect any tubing from inlets Gas 2 & Gas 3
for complete isolation.

Full calibration is a simple procedure requiring only two or three gases (one of
which is normally air – 20.95%). The gas values are user-selectable and can be
changed by using the front keypad (2) or the communications software described
in section 8, and the calibration values can be stored on file for later use.

Care must be taken to calibrate the analyser so that, whenever possible, the range
of measurement lies between the two calibration point extremes. For example, if
you are working at 10ppm but have calibrated the analyser between 21% and
100% then the analyser will be inaccurate. You would need to calibrate at, say,
1ppm and 1000ppm to be sure of good accuracy. The procedure is as follows:

1) Bearing in mind the points made above, decide which two (or three) gases

you are going to use for calibration. If you are constantly working at a
particular range of compositions then it would be wise to obtain small
cylinders of calibration gas with analysis certificates. Cambridge Sensotec
can supply these. Press the ENT button on the front panel keypad (2) to
access the menu system. The calibration function is option 1 on the menu
list, which can be scrolled using the UP and DOWN arrows. Press ENT
again to enter the calibration menu. The message “Use Calibration Gas on
Channel 1” is displayed for a moment. Use the UP and DOWN arrows to
select O2 HIGH, O2 MIDDLE or O2 LOW and press ENT to proceed. The top
line of the display shows the current calibration gas stored and the bottom
line of the display shows the prompts. If the gas value is not what you
require you can edit the value (in ppm scientific notation) using the up and
down and right arrows on the keypad. The cursor flashes underneath the
digit to edit. For example air (20.95%) should be entered as 2.095E+05ppm
(209,500ppm). Note that you cannot go backwards to edit a digit to the left
of the cursor. Instead keep pressing the RIGHT button and the cursor will
wrap around back to the beginning. Alternatively press ESC to start again.
Press ENT when you are ready to proceed.

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Scientific

Format

Meaning

Equivalent

ppm

Equivalent

Percent

1.000E+06ppm

1.000 x 1,000,000

1,000,000ppm

100.00%

2.095E+05ppm

2.095 x 100,000

209,500ppm

20.95%

1.000E+05ppm

1.000 x 100,000

100,000ppm

10.00%

1.000E+04ppm

1.000 x 10,000

10,000ppm

1.000%

1.000E+03ppm

1.000 x 1,000

1,000ppm

0.100%

1.000E+02ppm

1.000 x 100

100.0ppm

0.010%

1.000E+01ppm

1.000 x 10

10.00ppm

0.001%

1.000E+00ppm

1.000 x 1

1.000ppm

0.0001%

Table 3: Examples of common scientific format with their equivalent ppm and percent
values

2) The sensor needs to be exposed to the first calibration gas from a cylinder

(or exposed to ambient air, 20.95% if this is the calibration gas of choice)
using Gas 1 input on the rear. Allow several minutes to pass to flush the
sensor properly. Wait for the top line of the display (1) to become stable.
To complete the calibration press and hold the ENT button for two seconds.
During this time you will see a bar graph progress across the lower display.
The analyser will then recalibrate and display “O2 recalibrated” and then
return to normal run mode. The display will now correctly read the value
of the first calibration gas. Note that if the ENT button is released before
two seconds have elapsed, the recalibration will be aborted and when the
analyser eventually returns to run mode it will use the existing calibration.

3) Note that the analyser should ideally be calibrated at normal ambient

pressure. If the pressure correction mode is set to AUTO then it is still
possible to perform an accurate calibration at pressures other than ambient.
However above 25mbar (gauge) or below -25mbar (gauge) the display will
flash and “P?” will display to warn you that the pressure is either above or
below the range recommended for accurate calibration.

4) The analyser predicts the correct signal from the sensor during calibration

and if this is outside the range of expected values then the display will flash
and display “G?” to warn you that either the cal gas flowing over the sensor
is different to the value you have programmed OR the sensor may be old
and approaching the end of its life. Check before proceeding!

5) To calibrate against the second or third calibration gas, repeat the

procedure from 2 but this time press ENT followed by the UP or DOWN
button to scroll through to the “O2 Middle” or “O2 Low” screen. Flush the
sensor chamber with the second calibration gas allowing several minutes
for the new gas to flush through. Again please remember to always use
Gas1 input to apply calibration gas. Wait for the display to become stable
before pressing the ENT button for two seconds. The analyser will then
recalibrate and display “O2 recalibrated” and then return to normal run
mode. The display will now correctly read the value of the calibration gas.

6) The analyser is now correctly calibrated and will read accurately between

these two calibration points. Note that this procedure can be performed
remotely using the software described in section 8. You can now repeat
this process for the third calibration gas if required.

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7) If at any time, you encounter difficulties and wish to restore the machine to

its factory set calibration, use the configuration software provided and load
the default settings (described in section 7.18 below). Each machine is
provided with a unique file that contains the factory settings. This is
located on the memory stick provided and is copied onto your PC during
the installation process.

8) Note that the three calibration points are independent of each other so you

can calibrate the analyser in any order you desire. However please note
that O2 HIGH must always be greater than O2 MIDDLE which must always
be greater than O2 LOW. Typically the factory settings are: O2
HIGH=20.95%, O2 MIDDLE=0.1% (1000ppm) and O2 LOW=0.001%
(10ppm).

NB You must always perform a FULL calibration to achieve good accuracy.

7.8 Programming the Multiplex

The Rapidox 1100ZR3-H-PFC is fitted with three independent gas inlets on the
rear panel allowing up to three separate gas samples to be analysed. The
multiplex unit allows one or more of the sample gases to pass over the sensor and
can be programmed by the user to work automatically, sampling each gas in turn
for a given time, or manually where each gas inlet channel can in turn be switched
on or off:

1. Automatic: When the multiplex is set to Auto then each gas channel is

sampled for a set period of time (or switched off) by the user. The sequence
is repeated continuously until the user changes the program. For each gas
channel the user can select a sample time of 1,2,3,4,5,10,15,30 minutes or
1,2,6,12 or 24 hours. In addition the user can switch one of the channels
off. In this case the remaining two channels will sample alternatively. At
least two gas channels have to be on for the automatic mode to work. The
front LCD displays three circles indicating to the user which channel is
currently being sampled. If channel 1 circle is flashing then this indicates
that the closed loop output is under PFC control. See Table 4 for more
details.

2. Manual: When the multiplex is set to manual mode the user can set any

channel to “on” or “off”. Any possible permutation is allowed in this mode
including switching all three off. Note however in this instance the internal
pump will automatically switch off to preserve itself. This mode is useful if
only one single sample is required, or sampling the same gas from different
locations is desired. The front LCD displays three circles indicating to the
user which channel(s) is/are currently being sampled. In this mode the
letters “Man” also appear every few seconds to indicate that the analyser is
operating in this mode. If channel 1 is set to “on” and channels 2 and 3 are
set to “off” then the PFC closed loop is active and the channel 1 circle will

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flash to indicate this. See Table 4 for more details.

Symbol

Meaning



+/- “Man”

In automatic mode sampling channel 1 for selected time.

In manual mode channel 1 on and 2 & 3 off.
If the black circle is flashing then the closed loop output is under PFC control. If it is not

flashing then PFC closed loop control is suspended.



+/- “Man”

In automatic mode sampling channel 2 for selected time.

In manual mode channel 2 on and 1 & 3 off.

PFC closed loop control is suspended.



+/- “Man”

In automatic mode sampling channel 3 for selected time.

In manual mode channels 1 & 2 off and 3 on.

PFC closed loop control is suspended.



+ “Man”

In manual mode only all three channels are off. Note that the pump switches off if this mode
is set. PFC closed loop control is suspended.

 + “Man”

In manual mode only all three channels are on. PFC closed loop control is suspended.



+ “Man”

In manual mode only channels 1 & 2 on and 3 off. PFC closed loop control is suspended.

 + “Man”

In manual mode only with channels 1 & 3 on and 2 off. PFC closed loop control is suspended.

 + “Man”

In manual mode only with channels 1 off and 2 & 3 on. PFC closed loop control is suspended.

Table 4: Different permutations of channel indicator lights on the LCD

To program the multiplex press ENT on the keypad (2) and select menu option 2
using the up and down arrows or using the software described in section 8.6.
Press ENT to proceed. Use the UP and DOWN arrows to select “Auto” or
“Manual” and ENT to proceed. If “Auto” is selected then use the UP and DOWN
arrows to select a time period (1,2,3,4,5,10,15,30 minutes or 1,2,6,12,24 hours or
OFF) for each gas sample inlet in turn. If “Manual” is selected use the UP and
DOWN arrows to select “on” or “off” for each gas sample inlet in turn. Once all
three are programmed then the multiplex will start the sequence of sampling from
gas 1 inlet.

Note that you can only have one of the channels switched on at any time in the
auto mode. If “on” is selected then the option disappears from further menus as
you continue the programming sequence. You can have any combination of “off”
and “on” in manual mode.

7.9 Cleaning the Sensor

You can clean the sensor at any time by pressing ENT on the keypad (2) and
scrolling down to option 3 “Clean Sensor” or using the software described in
section 8.6. Press the ENT button to proceed. The screen displays “Clean
Sensor?”. Press ENT again and the cleaning will take place. The procedure takes
approximately five seconds and the LCD display shows the progress of the
operation. Once finished the analyser will take a moment to re-stabilise. The
sensor is cleaned each time the unit is switched on prior to operation. If you are
operating in gases with large amounts of soot, there is a risk that the sensor
surfaces will become contaminated with particulates, which will impair
performance if allowed to build up. The cleaning operation pumps oxygen
through the zirconia tube, which burns the particulates away from the sensor
surface.

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7.10 Alarms

The Rapidox is fitted with two independent and fully programmable alarm relay
outputs, which can be programmed to be either normally open N/O (closes on
alarm) or normally closed N/C (opens on alarm). You have the option of assigning
each alarm to the oxygen, or pressure (internal) as well as enabling the alarm relay
circuits, enabling an audible buzzer and enabling a visual warning on the screen.

The alarms can be programmed by the user via the keypad (2) on the front panel
or using the software provided (section 8.5.3 ). To change the alarm settings scroll
down the menu to no. 4 “Set Alarms” and press ENT. Now use the UP & DOWN
arrows to select “Alarm 1” or “Alarm 2” and press ENT. The next screen shows
the message “Assign To:”. Use the UP and DOWN arrows to select O2, or Pressure
depending on which measurement you want the alarm to work with, and press
ENT to proceed. The default is O2.

The next settings configure the behaviour of the alarm. Use the UP & DOWN
arrows to select ON or OFF for the following parameters:

1. OUTPUTS: This enables the rear panel relay outputs when ON is selected

2. AUDIBLE: This enables or disables the audible buzzer inside the unit

which will sound in an alarm condition

3. VISIBLE: This enables or disables warning messages on the LCD screen on

the front of the Rapidox. During an alarm condition either “AL1” or “AL2”
(or a combination of both) will flash at the bottom right hand corner of the
display.

4. POLARITY: This determines whether you are setting a rising or falling

alarm. Use the arrows to change the direction of the alarm to up or down.
A rising alarm means that the alarm will be silent at values below the set­point but as soon as the value rises above the set-point the alarm will be
triggered

5. SETPOINT: The current alarm set-point is displayed in scientific notation

with a flashing cursor under the first digit. Use the UP & DOWN arrows to
change the digit and the RIGHT arrow to progress until the correct value is
displayed. When done, press ENT to proceed to the next setting.

6. CONTACTS: The relay outputs can be set to either normally open (N/O) or

normally closed (N/C). The factory default is N/O, meaning the contacts
will close when an alarm condition occurs. Press ENT to save all the above
settings for the selected alarm.

Alarm 2 can be set in exactly the same way as described above and both alarm
circuits are completely independent of each other. Note that you must programme
all the parameters for each alarm for the settings to be saved. The bottom line of
the LCD will display “Alarm x set” (where ‘x’ is the selected alarm channel) to

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confirm that the settings have been saved.

The alarm circuit relays are accessed via the terminal block on the rear panel and
are clearly labelled. Alarm 1 is assigned to the terminals labelled “Alarm High”
and Alarm 2 is assigned to the terminals labelled “Alarm Low”. The relay circuit
is rated at 24V 0.5amps maximum. Under certain conditions (e.g. the sensor
becomes disconnected) the Rapidox will set the alarm channel to OFF to prevent
false alarms, and the relay contacts for the affected channel will go to the
programmed N/O or N/C setting. For more information please refer to Table 5 in
section 7.11 below.

7.11 Analogue Outputs

The Rapidox analyser provides various analogue outputs. The standard industrial
analogue outputs (0-10V and 4-20mA) for both oxygen, and internal pressure are
accessible via the terminal block (6) on the rear panel. These outputs have a 12
bit resolution (approximately 1 in 4000) and the lower and upper values are fully
user-programmable using the keypad (2) or the software provided (section 8). In
the case of oxygen, three output mode options are provided for setting the outputs,
in order to give the user maximum flexibility:

1. LIN (ppm): The linear oxygen output mode setting produces an output that is

scaled linearly between 0 and 10V (or 4 and 20mA). So, for example, if the
scale is set 0V = 0% O2 and 10V = 100% O2 then 5V would indicate an oxygen
reading of 50% O2. The scaling of this example is shown in the following plot,
from which other intermediate values can also be read. This setting is more
suitable for medium to high ranges of oxygen, or where the user wishes to
monitor oxygen over a narrow range.

Figure 4: Graph showing the linear output mode option for oxygen

"Lin(ppm)"

Line a r output mode

0

1.25

2.5

3.75

5

6.25

7.5

8.75

10

0 10 20 30 40 50 60 70 80 90 100

O2 ( %)

O

2

Volts output

4

6

8

10

12

14

16

18

20

O

2

mA output

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The following general formulae can be used to calculate the oxygen from the
voltage or current outputs when set to the linear output mode:

Output type Formula for calculating oxygen from analogue output signal

0-10V O2 = V

out

/ 10 * (O2H - O2L) + O2L

4-20mA O2 = (mA

out

– 4) / 16 * (O2H - O2L) + O2L

Where: O2L = user setting of oxygen for 0V or 4mA output 1

O

2H

= user setting of oxygen for 10V or 20mA output 1

V

out

= the measured voltage output in volts

mA

out

= the measured current output in mA

1

O2, O2L and O2H must all be in the same units.

2. LOG (ppm): This setting produces an output that is scaled logarithmically

between 0V and 10V (or 4 and 20mA). So, for example, if the scale is set to 0V
= 0.0001% (1 ppm) and 10V = 100% (1,000,000 ppm) then 5V would indicate
an oxygen reading of 0.1% (1000 ppm). This scale is more suitable for large
ranges of oxygen down to very low ppm levels. The scaling of this example is
shown in the blue line in following plot, from which other intermediate values
can also be read. For comparison, the red line shows the limitations of using
the linear oxygen output mode over the same range.

Figure 5: Graph showing the logarithmic output mode option for oxygen (blue) compared with

linear mode (red).

The following general formulae can be used to calculate the oxygen from the
voltage or current outputs when set to the log output mode:

"Log(ppm)": Log output mode

0

1.25

2.5

3.75

5

6.25

7.5

8.75

10

0.0001 0.001 0.01 0.1 1 10 100

O

2

( %)

O

2

Volts output

4

6

8

10

12

14

16

18

20

-4 -3 -2 -1 0 1 2

log(O2 (%))

O

2

mA output

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Output type Formula for calculating log10(O2) from analogue output signal

0-10V log10(O2) = V

out

/ 10 * log10(O2H / O2L) + log10(O2L)

4-20mA log10(O2) = (mA

out

– 4) / 16 * log10(O2H / O2L) + log10(O2L)

Where: O2L = user setting of oxygen for 0V or 4mA output 2

O

2H

= user setting of oxygen for 10V or 20mA output 2

V

out

= the measured voltage output in volts

mA

out

= the measured current output in mA

2

O2, O2L and O2H must all be in the same units.

Note: O

2

= 10

log(O2)

3. RAW (mV): This setting is for certain customers who like to monitor the raw

sensor EMF signal. The signal from a sensor goes from approximately -50mV
at 100% O2 through zero at approx 5% O2 and to +1000mV at extremely low O2
levels. So, for example, if the scale is set to 0V (output) = -50mV (sensor
voltage at approximately 100% O2) and 10V (output) = 250mV (sensor voltage
at approximately 1ppm O2) then 5V would indicate a sensor voltage of 100mV.
The scaling of this example is shown in the following plot, from which other
intermediate values can also be read.

Figure 6: Graph showing the raw sensor mV output mode option for oxygen

The following general formulae can be used to calculate the oxygen sensor raw
voltage (O

2mV

) from the voltage or current outputs when set to the raw sensor

voltage output mode:

"Raw(mV)"

Se nsor mV output mode

0

1.25

2.5

3.75

5

6.25

7.5

8.75

10

-50 0 50 100 150 200 250

Raw sensor voltage (mV )

O

2

Volts output

4

6

8

10

12

14

16

18

20

O

2

mA output

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Output type Formula for calculating sensor mV from analogue output signal

0-10V O

2mV

= V

out

/ 10 * (O

2mVH

- O

2mVL

) + O

2mVL

4-20mA O

2mV

= (mA

out

– 4) / 16 * (O

2mVH

- O

2mVL

) + O

2mVL

Where: O

2mVL

= user setting of oxygen mV for 0V or 4mA output

O

2mVH

= user setting of oxygen mV for 10V or 20mA output

V

out

= the measured voltage output in volts

mA

out

= the measured current output in mA

To modify the oxygen analogue output range scroll down the menu to option 5
“Set Outputs” and press ENT. Use the UP & DOWN arrows to select the output
type either “lin(ppm)”, “log(ppm)” or “raw(mV)” and press ENT. You can now edit
the lower and upper values using the UP & DOWN and RIGHT arrows. Once
programmed the new values remain in the memory until they are edited again in
the future.

Note that the voltage (0 to 10V) and current (4 to 20mA) outputs are locked
together, so that these outputs cannot be set independently of each other. In
normal operation therefore, 0V output always corresponds to 4mA and 10V
always corresponds to 20mA output.

During initial warm up of the Rapidox when the display reads the serial number
the output sent to the rear terminal for oxygen will stay at 2mA (1V) which is the
standby signal. If at any stage a sensor becomes disconnected internally, or the
signal exceeds the measurable range for that sensor, then the display will indicate
there is a fault and the outputs will change to 1mA (0.5V) which is the sensor fault
signal. This will recover as soon as the sensor is reconnected and the fault
cleared. Additional current and voltage signals are provided by the analyser to
give an indication of various conditions and these are described in Table 5 below,
together with the status of the alarms during the condition:

O2 Analogue Outputs

Description Explanation Alarms

(3)

Current

(1)

(4-20mA)

Voltage

(2)

(0-10V)

1mA 0.625V Fault

There is a sensor fault on the oxygen

sensor, and/or the temperature sensor
has a fault condition, and/or the
pressure mode is set to automatic
(pressure compensation active) and
the pressure sensor has a fault

condition.

De-activated

2mA

1.25V

Start up

The analyser is still initialising.

De-activated

2.5mA

1.5625V

Sensor under range

The sensor reading is under range.

Active

3mA

1.875V

Sensor over range

The sensor reading is over range.

Active

3.5mA 2.1875V

Sensor operating out of
specification

The sensor reading is in range but the

temperature sensor reading is out of
range, and/or the pressure mode is set
to automatic (pressure compensation
active) and the pressure sensor is out

of range.

Active

4 to 20mA 0 to 10V Normal operating output

The O2 sensor and associated

(1)

sensor(s) are operating normally and

readings are in range.

Active

Table 5: Analogue output settings and alarm status for certain conditions

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Notes:
1 The current outputs are active self-powered outputs - they are not loop powered i.e. they are current source outputs.
2 The voltage (0 to10V) outputs produce non-zero voltages during start-up, fault and over/under range conditions - if

1V to 5V outputs are required, with these conditions indicated by corresponding voltages between 0V and 1V, the
current outputs can be used, with a 250 Ohm load resistor.

3 Alarms are de-activated during start up initialisation, and when a fault condition occurs on the assigned sensor.

Note that the secondary auxiliary outputs on this version of the Rapidox are
replaced with outputs that control the PFC. Please see Appendix 1 at the end of
this manual for detailed instructions on how the PFC is programmed, tuned and
used.

7.12 Setting the Display Units

The notation used by the display is fully programmable to suit your needs using
the keypad (2) or the software provided (section 8.4). The following options are
available to you:

1. Oxygen: The oxygen reading can be displayed in percent (e.g. 20.95%),

ppm (e.g. 10.0ppm) or scientific (e.g. 2.095E+05ppm). If percent is selected
the Rapidox will display oxygen as a percentage down to 0.1% and ppm
below this value. There are also options to display the oxygen reading in
terms of a pressure (units will be the same as the units selected for
pressure) or a nitrogen balance (%N2) reading. In this case the reading
displayed is 100-O2% =N2 so for example in air 21% the nitrogen balance
reading will display 79% N2. Note that this is NOT an actual nitrogen
reading. The default setting is percent.

2. Pressure: The reading can be displayed in mbar, bar, psi, torr or kPa. The

default setting is mbar.

To program these options scroll down to menu no. 6 “Set Units” and press ENT.
Use the ENT key to progress through the list and the UP & DOWN keys to select
the required units. Once selected press ENT to store and return to run mode.

7.13 Setting the Display Options

The user can select the LCD refresh rate and the format of the line 2 display using
the keypad or the software provided. Scroll down the menu to option no. 7 “Set
up Display” and press ENT. Use the UP & DOWN arrows to select either the LCD
refresh rate or Line 2 Options:

1. LCD Refresh Interval: The frequency of the display update can be selected

from 0.1 to 1.5 seconds. The current setting can be edited using the same
method as described previously. Once edited press ENT to store and return
to the main menu. The default setting is 0.3 seconds.

2. Line 2 Options: The information displayed on line 2 of the LCD can be

chosen by the user. The options are None or Pressure (displayed in mbar,
bar, psi, torr or kPa. Use the UP & DOWN arrows to select the required

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option and press ENT to store and return to the main menu. The default
setting is Pressure. Note that on the Heller coded machines the second line
display is switched off by default.

7.14 Pressure Correction Mode

The user has the option of using the reading from the internal pressure sensor to
automatically correct for changes in gas pressure and hence oxygen pressure. A
manual pressure correction value for ambient pressure conditions can also be
entered to improve accuracy of the correction (factory setting is 1013 mbar
absolute). To access this function scroll down to menu option 8 “Pressure Mode”
and press ENT. The desired mode can then be selected using the UP & DOWN
arrows and pressing ENT to store and proceed. The two modes available are:

1. None: If this mode is selected then there is no pressure correction

performed on the oxygen reading. The pressure and oxygen sensor act
independently. If the sensor is working in air (20.95%) and the pressure is
doubled then the reading will also double to 41.9%. This is the correct
oxygen partial pressure in air at 2 bar since there is a simple linear
relationship between pressure and concentration.

2. Auto: This is the factory default setting. If the Auto mode is selected then

the Rapidox 1100 uses the reading from the internal pressure sensor to
correct the oxygen partial pressure and maintain a concentration reading. If
the sensor is working in air (20.95%) and the pressure suddenly jumped to,
for example, 500 mbar above atmospheric, the oxygen reading would
remain at 20.95% because the sensor has been corrected for the pressure
change. This allows users who are working with fluctuating input
pressures to maintain a ‘meaningful’ reading of oxygen concentration that
will only be affected by changes in gas composition and not gas pressure.

Note that when this mode is activated the user will be asked to enter a value for
the current ambient pressure to slightly improve the accuracy of the correction.
The factory default is 1013mbar which is the average ambient pressure for the UK.
The ambient pressure at your location will depend on altitude and prevailing
weather conditions. This correction is extremely small in this Rapidox version so
if you don’t know the pressure please leave it at 1013mbar.

7.15 Setting the Baud Rate

If you are using the software for data logging you can chose the communications
speed (Baud Rate) by scrolling down the menu to no. 9 “Baud Rate” and using the
UP & DOWN arrows to select either 9600 or 57,600. Press ENT button again to
store and return to normal operation. The default factory setting is 57,600.
However if you are using an older PC you can decrease this to 9600 to improve the
reliability of the software and data communications.

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7.16 RS232 / RS485 Port

It is possible to factory set the data communications port to either RS232 or
RS485. Once configured at the factory it is not possible to change unless the unit
is returned to Cambridge Sensotec Ltd.

Data from the Rapidox is sent on demand to the 9-way 'D' type socket (8) on the
rear panel and can be read using a simple terminal programme such as
'HyperTerminal' in Windows, or with the user's own custom software.
Alternatively a simple and convenient data logger programme is included with the
supplied software and is described in section 9 below.

7.16.1 RS232 Protocol

Oxygen data can be read from the RS232 port at the back of the Rapidox. The
default RS232 configuration is 57600-8-N-1, as shown in this example for COM1:

Figure 7: Rapidox default COM properties box

Alternatively, the baud rate can be reduced to 9600 via the “Set Baud Rate” menu
item, using the front panel keypad on the Rapidox. This setting is stored in
EEPROM.

Connection: Connect to RS232 socket at the back of the Rapidox using a 9 way D­type plug. Signals are as follows:

Rapidox D-type Socket: PC/PLC:
Pin# 2 = Data Out  Data In (RX)
Pin# 3 = Data In  Data Out (TX)
Pin# 5 = Common/Gnd -- Common/Gnd

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Figure 8: Rapidox RS232 pin configuration

All other pins (1,4,6,7,8,9) = Don’t care

Reading Data: Data is read using command “D”. Send the single character “D” to
the Rapidox. The Rapidox replies with one of the following responses. All valid
responses end with [CR] & [LF] (where [CR] = ASCII 13 and [LF] = ASCII 10).

Response: !Initialising[CR][LF]
Meaning: Rapidox is still initialising

Response: !Sensor heating[CR][LF]
Meaning: Rapidox is still heating sensor to operating temperature

Response: !Sensor cooling[CR][LF]
Meaning: Rapidox is still cooling sensor to operating temperature. This can

happen when switching from Normal to Helium operating mode.

Response: !Cleaning sensor[CR][LF]
Meaning: Rapidox has finished heating sensor and is cleaning the sensor for 5

seconds

Response: !User setup active[CR][LF]
Meaning: The configuration menu has been activated via the front panel

keypad. The menu will automatically time out 60 seconds after the
last key was pressed, or press the keypad’s ESC key to return
immediately to normal run mode.

Response: !Possible sensor fault[CR][LF]
Meaning: The sensor has failed to reach operating temperature within 10

minutes from power up. This may be due to the age of the sensor, or
because a high thermal conductivity gas is being used.

Response: !No sensor or sensor fault[CR][LF]
Meaning: Sensor is not connected, or there is a fault in the sensor

Response: d2.959E+05,-1.426E+01,2.000E+00,50.0,23:19:40,

14/01/00,,,ALM1&2,0,G1[CR][LF]

Meaning: “d” means data is being sent

RS232

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“2.959E+05” is Oxygen reading in ppm
“,” = data separator
“-1.426E+01” is Oxygen sensor reading in mV
“,” = data separator

“2.000E+00” is the internal pressure sensor reading in bar (gauge)
“,” = data separator
“50.0” is the closed loop PFC signal in terms of a percentage where

0% = 4mA and 100.0%= 20mA
“23:19:40” is Rapidox time
“,” = data separator
“14/01/00” is Rapidox date in DD/MM/YY format
“,,,” = data separators

“ALM1&2” means both alarm conditions 1 and 2 exist *

“,” = data separator

“0” = sensor state code (0=OK, 1=O2 O/Range, 2= O2 U/Range, 3=O

2

Fault, 4=Press. U/Range, 5=Press. O/Range, 6= Press. Fault**)
“G1” is the current channel being sampled (G1,G2,G3,M0-M7***)
[CR] = ASCII 13 (Carriage Return character)
[LF] = ASCII 10 (Line Feed character)

* If no alarm conditions exist, this data is empty, so the response would look like d2.959E+05,-

1.426E+01,2.000E+00,50.0,23:19:40,14/01/00,,,,0,G1[CR][LF]
** These are binary codes so fault combinations produce other numbers
*** Please refer to Table 6 below for a full explanation about these codes.

Response: ?
Meaning: “D” command was not recognised. Try to send it again.

7.16.2 RS485 protocol

Please contact Cambridge Sensotec for further information on this feature.

7.17 Printing

If you have purchased the printer option then you have the option to print out
various data from the analyser straight on to thermal paper. Simply connect the
printer to the unit using the serial socket on the rear of the machine and make
sure the printer is switched on (battery and mains versions are available). To
print the live values on the LCD at any time simply press the RIGHT arrow button
on the front panel. Each push of the button will print out the serial number
followed by the data in a tabbed format followed by a blank line. If the button is
held down, the printer will keep printing data (but not the serial number).

When the printer is first connected or turned on, a “start-up” message like the one
displayed on the LCD when the Rapidox is switched on will be printed, and will
look like this:

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Cambridge

Sensotec Ltd

Rapidox 1100ZR3-H-PFC

Oxygen Analyser

S/N: 210XXXX

FW v XX.XX.XX.XX

7.18 Load Defaults

If you make a mistake programming the Rapidox it is possible to restore the
machine back to its factory settings by loading the unique default configuration
that is supplied on your software memory stick. The default set-up can only be
accessed using the software provided. Please see section 9.23 for further details.

Alternatively, you can reset to ‘generic’ factory defaults directly from the front
panel keypad. Press ENT to enter the user setup menu and select menu option 11
“Load Defaults” and press ENT to proceed. The next screen will say “Load
Defaults ?” with the prompt to press and hold ENT for 2 seconds to confirm. To
complete this press the ENT button until the bar graph has completed and the
screen says “Defaults Loaded” This will give you all the basic settings that are
factory set. You will now need to re-calibrate the sensor and check all the settings
are suitable.

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8. Rapidox Software Instructions

Please note that additional instructions for the PFC pages of the software are
supplied in Appendix 1 at the end of this manual as this feature is a “bolt on”

8.1 Software Installation

It is possible to programme a range of variables to the Rapidox using an RS232 (or
RS485 if configured) link with a PC running MS-Windows (all versions) and the
supplied Rapidox software. The software is supplied on a memory stick which
contains a setup.exe file to install.

The software has been tested successfully on most language machines including
Chinese, Korean & Japanese and all current versions of Windows operating
system. We do not recommend the use of Vista as connecting devices to this
operating system can be problematical at best.

Note that software is ‘regionally aware’ and will therefore accept and display data
using the decimal separator that is set in the PC’s Regional Settings in the Control
Panel. For example, in the UK or US, you might enter the value 2.5 - in
continental Europe this would normally be entered as 2,5 assuming the PC’s
Regional Settings have been set up to use ‘,’ as the decimal separator.

8.2 Getting Started

Make sure that the Rapidox is connected to a free serial port on the rear of your
computer. These will nearly always be COM1 or COM2 but the software will scan
through the ports until it finds the Rapidox. The analyser must be switched on for
this to succeed and while you are communicating with it. On start up the
software will locate the Rapidox and display the following page:

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Figure 9: Rapidox configuration page. Note the actual values used may differ from those shown

above.

The yellow status box at the bottom will display confirmation that the Rapidox
was found and the result of the last action, or any error messages if there is a
problem with communication. If you experience problems check that your serial
cable (supplied) is correctly fitted to a valid serial port. Also check the status of
your COM port settings in Device Manager accessed by clicking START – Settings

- Control Panel.

In PFC versions of the Rapidox an additional panel is displayed at the foot of the
main software window as shown in Figure 10. See Appendix 1 for full details of
this feature.

Figure 10: Additional panel displayed when running a PFC enabled analyser

8.3 On-Screen Help

You can access the on-screen help facility at any time by clicking on the help
menu on the menu bar and select the ‘Help’ option or press F1.

8.4 Configuration Page

The configuration page is split into three, and you can switch between them by
clicking on the tabs labelled “Config 1”, “Config 2” or “Alarm Config”. Each page
allows the user to reprogramme an array of variables used by the Rapidox. Once

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written to the Rapidox, the new variables remain permanent until overwritten.

To read the current configuration stored in your Rapidox select ‘Read Analyser
Configuration’ from the ‘File’ menu, or click the ‘Read’ button on any of the
‘Config’ pages. Note that the entries in the boxes on the RHS (under the ‘Write’
button) will turn red if the value is different to that just read and a red asterisk
will appear next to the ‘Write’ button to warn you that a change has been made.
The left-hand set of grey text fields (‘read fields’) will be updated with the current
configuration data. To save this information (e.g., if several people share the same
instrument) click the long copy (‘>>’) button (between the ‘Read’ and ‘Write’
columns) on any of the ‘Config’ pages in order to transfer the data into the edit
boxes, select ‘Save Configuration as’ from the ‘File’ menu and choose a filename.
This data set can be subsequently reloaded at any time by selecting ‘Load
Configuration File’ from the ‘File’ menu and then selecting the folder where the
configuration files have been stored.

If at any time you wish to restore the machine to its factory default settings select
‘Default Configuration’ from the ‘File’ menu to load these values. The software
will search for a unique ‘.rxc’ file that is loaded onto the PC during the software
installation. The filename is 2100***.rxc where *** is the last three digits of the
serial number located on the rear of the machine. This file is also located on the
memory stick that came with the machine. Normally this file is located in “My
Documents” directory but if the software cannot locate it then it will ask you for
the serial number to help it search. With the correct rxc file loaded into the ‘Read’
columns, simply click ‘>>’ (copy) to transfer the defaults into the edit boxes and
then click any of the three ‘Write’ button to load them back into the Rapidox.

The right-hand set of white editable text fields (‘write fields’) is used to enter new
values to be programmed into the Rapidox. The values in these fields can either
be entered manually, or copied across from the ‘read fields’ by clicking the vertical
‘Copy’ button, and then edited as required, however greyed boxes under the
‘Write’ buttons are not editable as they contain calibration data; they can only be
changed by copying data across from the ‘Read’ fields. Note that when you click
on the copy button all three ‘Config’ pages are updated at the same time and there
is no need to repeat the action when you toggle to the other page. Alternatively,
you can load saved configuration data by selecting ‘Load Configuration’ from the
‘File’ menu and selecting the required file. In order to programme the analyser
select ‘Write configuration to the analyser’ from the ‘File’ menu, or click the ‘Write’
button on any ‘Config’ page.

8.5 Reconfiguring the Analyser

The on-screen edit boxes contain variables that can be reprogrammed into the
Rapidox in exactly the same manner as using the front panel keypad. For a full
description please refer to the relevant section in this manual.

The user can choose whether to use ppm or percent notation to edit the text boxes,
where appropriate, by selecting the ‘UNITS’ menu and clicking on ‘Percent’ or

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‘ppm’. To access a field, either click inside it or use the TAB key to scroll through
them. The field parameters are as follows:

8.5.1 Config 1 Screen

1) Oxygen Range: Not available for the Rapidox 1100ZR3-H-PFC

2) Oxygen Units & Format: See Section 7.12 for a full description. Use the

drop down box to select PPM EXPONENTIAL, PPM MIXED, AUTO%/PPM,
PRESSURE or N2 BALANCE. The default setting is AUTO%/PPM.

3) Oxygen Analogue Output Mode: See section 7.11 for a full description.

Use the drop down menu to select RAW, LIN(ppm) or LOG(ppm) as the
mode of output for the 4-20mA and 0-10V signals. The default is LIN(ppm)

4) Temperature Units/Enable: Not available for the Rapidox 1100ZR3-H-PFC

5) Pressure Units: See sections 7.12 for a full description. Use the drop down

menu to select MBAR, KPa, TORR, BAR or PSI as the unit for pressure
measurement. The default setting is MBAR.

6) Pressure Correction Mode: See section 7.14 for a full description. Use the

drop down menu to select NONE or AUTOMATIC. The default setting is
AUTOMATIC.

7) Operating Mode: Not available for the Rapidox 1100ZR3-H-PFC

8) Auxiliary Output Parameter: Not available for the Rapidox 1100ZR3-H-

PFC (fixed to the pressure sensor)

9) LCD Refresh interval: Use the drop down menu to select a refresh rate for

the LCD (min 0.1, max 1.5 sec). The default is 0.3 seconds.

10) LCD Second Line Option: Please note on Heller coded machines the

second line display is disabled. See section 7.13 for a full description. Use
the drop down menu to select PRESSURE or NONE. The default is
pressure.

11) Pump Flow Rate: Please note on Heller coded machines the pump flow rate

is fixed to 100%. See section 7.5 for a full description. Use the drop down
menu to select a pump flow value from 10-100% or OFF. The default is
100%.

12) Multiplex Mode: See section 7.8 for a full description. Select Manual or

Auto from the drop down menu. The default is Manual set to channel one
only.

13) Gas Sample Duration: See section 7.8 for a full description. Use these

three drop down boxes to select the sample time required in automatic

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mode or if manual mode is selected chose between “off” and “on” for each
of the three channels. Note that you can re-label the three sample channels
by clicking on the label text. The new names will be recorded and
displayed on the graph to assist you. The default time is set to 10 minutes
for each channel.

14) Gas 1 Priority: This function is part of the PFC control software and when

set to ON will force the multiplex to alternate between channel 1 and the
other channels in turn. In other words the sequence changes from
1,2,3,1,2,3 to 1,2,1,3,1,2,1,3. This allows the PFC to control the gas more
accurately and consistently because only samples from channel one are
used. The default is ON.

15) Password option: See section 7.6 for a full description. The password is

factory disabled and set to 0000. Use the drop down menu to enable or
disable the password feature and the password box **** can be used to
enter a new password. Note that you will be prompted to enter the original
password to make changes to the password or its status.

8.5.2 Config 2 Screen

Figure 11: Configuration 2 page. Note the actual values used may differ from those shown above.

16) Calibration Gas 1, 2 & 3: These boxes are greyed out in this version and

the data is for information purposes only. If you want to change the current
calibration gas then follow the procedure given in section 8.7.

17) Calibration Constant A B & C: These boxes contain the calibration

constants that the Rapidox calculates automatically when you perform a
calibration. You will see that they change each time you perform a new
calibration. Generally the air value should be approximately -10mV and a

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low ppm value (e.g. 10ppm) would be approximately 180mV.

18) O

2

Analogue Output (0V/4mA & 10V/20mA): Use these two boxes to set

the High and Low oxygen values for the analogue outputs (6) on the rear
panel. For example if you want 4mA to represent 1% and 20mA to
represent 21% then enter these two values into the appropriate boxes. The
value can be entered either in % or ppm depending on the units selected.
The default is %. The default values are 25% for the high setting and

0.001% for the low setting.

19) Auxiliary Analogue Output (0V/4mA & 10V/20mA): Use these two boxes

to set the High and Low auxiliary (pressure sensor) values for the analogue
outputs (6) on the rear panel. For example if you want 0V/4mA to represent
0mbar and 10V/20mA to represent 100mbar then enter these two values
into the appropriate boxes. The units are fixed in mbar.

20) Absolute Ambient Pressure: Use this box if you want to enter the current

ambient pressure (in mbar). This value is used in the automatic pressure
correction function only and provides enhanced accuracy in the correction.
The default is 1013mbar which is the average ambient pressure in the UK.

8.5.3 Alarm Config Screen

Figure 12: Alarm configuration screen. Note the actual values used may differ from those shown

above.

21) Alarm Source: Use the drop down box to assign a detector to the alarm. If

you want the alarm to be based on oxygen readings select oxygen from the
drop down list. The choices are: oxygen or pressure.

22) Alarm Outputs: This option enables or disables the alarms on the rear

panel (labelled Alarm High +/- and Alarm Low +/-). Make sure these are

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enabled if you wish to use the signals from the alarm circuit.

23) Audible Alarm: This option enables or disables the audible buzzer fitted to

the Rapidox internally. When an alarm condition occurs the buzzer will
emit a continuous noise to alert the operator.

24) Visible Alarm: This option enables or disables the visual warning on the

front LCD. When enabled and an alarm condition occurs the message
“AL1” or “AL2” (or a combination of both) will flash in the lower right hand
corner.

25) Rising or falling Alarm: This option allows the alarm to be set as a rising or

falling type. If the alarm is rising then the reading must rise above the set­point for the alarm to be activated. If the alarm is falling then the reading
must fall below the set-point for the alarm to activate.

26) Contacts N/O or N/C: This option allows the user to programme how the

relay contacts are set on the rear panel. Normally Open means that the
contacts are open circuit when an alarm is not activated and Normally
Closed means that the contacts are closed when the alarm is not activated.

27) Alarm Setpoints: Use this box to programme the set-point value at which

you want the alarm to activate. The units are in %, ppm or mbar depending
on which sensor you have assigned to the alarm.

Once you have finished editing the parameters, select ‘Write Configuration to
Analyser’ from the file menu and the new data set will be written to the Rapidox.
The Rapidox is reprogrammed using the new configuration. The software then
reads the new settings back from the Rapidox and displays them in the boxes on
the left-hand side confirming that the configuration was successful. When you
have finished programming the analyser for new calibration gases you must
recalibrate the instrument to benefit from the changes.

8.6 On-Screen LCD

It is possible to display an LCD emulator on the desktop of your PC. This
reproduces exactly the display on the Rapidox unit and is convenient if you are
some distance away from the machine. To activate the LCD select the UTILITIES
menu and select the LCD on option. This will display a small window showing
the LCD that can be positioned independently anywhere on the desktop.

Figure 13: On-screen LCD. The “Alarms” panel is part of the PFC and is described in detail in

Appendix 1.

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The blue LED indicator will flash to show that the display is updating.

8.7 Remote Calibrating and Cleaning

With the on-screen LCD display active it is possible to remotely calibrate the
analyser and clean the sensor. Click on the down arrow icon in the bottom right­hand corner of the LCD display to expand the window:

Figure 14: Remote calibration and clean function. The “Alarms” panel is part of the PFC and is

described in detail in Appendix 1.

Use the four buttons to calibrate or clean the sensor directly from the PC. Before
calibrating the analyser with gas, make sure that you know the exact O2
concentration in your gas bottle AND you have a calibration certificate from the
gas supplier confirming the concentration. You can calibrate the analyser in any
order but remember that the gas value for O2 High must be greater than the gas
value for O2 Middle, which must be greater than the gas value for O2 Low. Note
that you must only use Gas 1 inlet channel when calibrating. Gas 2 and Gas 3 are
disabled to prevent cross-contamination. A warning message to this effect is
displayed during the calibration sequence (see Figure 15). Allow sufficient time
for the calibration gas to pass over the sensor and let the reading on the LCD
stabilise. This is extremely important to perform a successful and accurate
calibration.

The software uses the three calibration gas values already stored in the Rapidox as
a starting point. These are typically High = 20.95%, Middle = 0.1% and Low =

0.001% as set in the factory but may be different if the user has recalibrated with
other gas values in the past. Either way you are given an option to change the cal
gas value before proceeding to the actual calibration. Assuming you are using
fresh air (20.95%) to calibrate O2 High then simply click on the button labelled
“Calibrate High O2” to see the following:

Figure 15: Warning message to remind you to ONLY use Gas Inlet 1 for calibrating the analyser.

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Figure 16: Calibration Gas Confirmation Screen.

If the current stored value is correct and matches your cal gas value then simply
click “Yes” to proceed. If you are using a different value to the one you see on the
screen then click “No” to change it as shown below:

Figure 17: Calibration Gas Update Screen.

Enter your new value in the units as instructed and click “OK” to proceed. This
value will then be stored until you want to change it again. You will now see the
following screen:

Figure 18: Calibration Confirmation Screen.

This is your final chance to change your mind before committing to a calibration.
Check carefully that the gas value on the screen actually matches the value of your
calibration gas before clicking on “Yes” to complete the calibration. At this point
you should observe that the LCD display will reset itself to the correct calibration.
You can now proceed with the rest of the calibration process by selecting the
Middle and Low gases in the same manner.

8.8 Calibration Error Messages

During the calibration process described in 7.7 above it is possible to receive
screen error messages as described here.

1) Bad Sensor Reading: The Rapidox software makes a prediction of the

expected sensor mV for each calibration gas value entered. If the mV signal
coming from the sensor is out of the expected range the following message
is displayed:

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This normally indicates one of two things: that you are using the wrong cal
gas value compared with the actual gas flowing over the sensor OR the
sensor is getting old and can no longer output the expected signal required
for a healthy calibration.

2) Bad Pressure Reading: The Rapidox software checks to see what the gas

pressure is before allowing the calibration to continue. If the pressure is
outside the range -25mbar to +25mbar (gauge) then the following message
is displayed:

This normally indicates that you are allowing gas from a cylinder set at too
high pressure to enter the analyser. Try displaying the pressure reading on
the second line of the LCD and adjusting the gas regulator to trim it close to
0 mbar. If you are using a standard gas regulator then try switching off the
sample pump on the rear of the analyser OR better still use a demand flow
regulator and allow the gas to enter the analyser from the draw of the
pump.

Note that the above are only advisories and you can proceed with the calibration if
you believe everything is checked and correct.

8.9 Software Utilities

The utilities menu is located on the main file menu as shown below:

Figure 19: Software Utilities Menu

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8.10 Setting Analyser Date and Time

The current date and time of your PC are displayed on the configuration screen
and can be loaded into the Rapidox by selecting the Utilities menu and clicking
the ‘Set date and time’ option. This information is used in the RS232 data string
for data logging purposes. Make sure that your PC clock is set correctly before
using this function, as you cannot edit the date and time shown by the Rapidox
software. The date and time formats displayed are those set in the PC’s Regional
Settings.

8.11 Log Diagnostics For

Use this option to log diagnostic data that can be e-mailed to Cambridge Sensotec
to help diagnose problems. Select the time you want to log the data for and then
wait for the logging to complete. During the diagnostic logging period the yellow
status box will display the location of the logged data file which will be sent to the
main Rapidox program directory. This file name includes the serial number, date
and time to make it easily recognisable. Please e-mail this file to

[e-mail] together with a description of the problem.

Figure 20: Example of a diagnostics file name and the storage location

8.12 Show / Hide LCD

Use these options to display or hide the on-screen LCD display as shown in Figure

11. The software remembers your last instruction each time the program is re­started.

8.13 Image Grabber

This is a simple function to allow the user to copy the software screens into the
Windows clipboard. This is useful for diagnosing problems; allowing a quick and
simple way of sending the Sensotec technicians actual screen shots of the
software. To recover the images simply press CTL+V to paste.

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9. Data-Logging Software

9.1 Introduction

The Rapidox software includes a full data logging facility. Data can be saved to a
file automatically at regular intervals and the format is compatible with modern
spreadsheet programmes such as MS-Excel. A live-time graphing facility is also
included which has many powerful features. Note that the data logging facility
will only function if the analyser is in NORMAL run mode.

9.2 Auto-Log Feature

A special feature of this software is an “Auto-Log” option which can be selected
from the tab labelled “Data-logging”. If this option is selected then the next time
the software is started the data-logger will begin automatically without any
instruction from the user:

Figure 21: Auto Logging Feature (enable or disable)

9.3 Setting up the Data Logger

Click on the tab labelled ‘Data Acquisition’ to display the following page:

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Figure 22: Data Logging page

During logging, data from the analyser is shown in the central area of this page.
The data is displayed in the following columns: time (in seconds), the raw signal
from the sensor (in mV), the oxygen value (in ppm scientific notation), pressure in
the units you have chosen, the time (in regional format), the date (in regional
format), and the status. The status message possibilities are listed as follows:

Message

Meaning

ALM1

Alarm 1 is activated

ALM2

Alarm 2 is activated

ALM1&2

Both alarms are activated

G1

 Auto mode sampling channel 1

G2

 Auto mode sampling channel 2

G3

 Auto mode sampling channel 3

M1

 Manual mode channel 1 on

M2

 Manual mode channel 2 on

M3

 Manual mode channels 1 & 2 on

M4

 Manual mode channel 3 on

M5



Manual mode channels 1 & 3 on

M6



Manual mode channels 2 & 3 on

M7



Manual mode all three channels on

M0



Manual mode all three channels off

Table 6: List of possible status messages shown on the data-logging table

Following this code is ,X,Y,Z which is additional information for PFC control,
where either a “0” or “1” is displayed. “0” means off and “1” means on. X =
software alarm 1, Y = software alarm 2 and Z = gas flow alarm. For more
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described in detail (sections 40,41 & 44).

To start data logging select the frequency of measurement by entering a time and
selecting a unit from the drop down list. For example if you wish to log data once
every minute type 1 in the box and select ‘Mins’ from the drop down menu.

You can open the NOTES window at any time by selecting NOTES from the ‘Data
Logger’ drop down menu. A small text box appears in which you can type a text
message. This note is then saved as a header in the data file set and can be viewed
along with the data.

You can either choose to have data logged continuously until ‘Stop’ is selected
from the Data Logger menu, or you can choose to set a time limit for data logging
by checking the box labelled ‘Time Limit’, setting the duration in the ‘Run For’ box
and selecting units with the drop down list. For example if you wish to log data
for thirty minutes type ‘30’ in the box and select ‘Mins’ from the drop down list.

9.4 Running the Data Logger

If you wish to save the data into a file for later use, check the ‘Save to File’ box
before selecting ‘Run’ from the Data Logger menu. You will be prompted for a file
name and location before data logging commences. The file and path information
will appear in the box at the top of the page labelled ‘Data File Name’. If you
forget to select file saving before starting a run, you will nevertheless be prompted
at the end as to whether you wish to save the run data.

The blue progress bar displays the state of completion of the run, and the blue box
to the right of it the same information as a percentage. You can stop the run at
any time by selecting ‘Stop’ from the Data Logger menu. The yellow Status bar at
the bottom of the page gives information about the data logging operation.

Once data logging is complete you may open the text format data file using any
compatible spreadsheet programme such as MS Excel, and use the data to
generate plots and reports.

You can pause the data logger at any time by selecting ‘data logger’ and ‘pause’.
Repeat to continue logging from where you left off, noting that the clock keeps
ticking during the pause period.

9.5 Auto Date Stamped Files

If you are planning to run the data logger for extended periods of time then you
should consider checking the ‘Auto date stamped file’ option. This feature will
save the data at midnight for the previous twenty four hours and so on until the
data-logging is complete OR the user interrupts. The data file is stored with a date
suffix in brackets in yy-mm-dd format.

This feature ensures that data is saved periodically in sensible sized files. This

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will prevent the computer from crashing and will also ensure that the data is small
enough to fit into an Excel spreadsheet

As an example, the user wishes to run the data-logger for seven days recording
every minute starting at lunchtime on 12th November 2005. He starts the data
logger with the auto-date stamp function enabled. When prompted he gives the
filename as test1. In this situation the data logger will run from lunchtime to
midnight and then save the first file as test1 (2005-11-12). The data logger then
clears and continues for another twenty four hours until midnight the following
day. The data is then stored as test1 (2005-11-13). This will continue for seven
days when the data-logger will finish.

After this the user will have a sequence of files:

test1 (2005-11-12).txt
test1 (2005-11-13).txt
test1 (2005-11-14).txt

And so on. Combined together they represent all the data over the last seven days.
Note that the Rapidox uses the computer clock and date to perform this action, so
make sure that they are correct before starting a run.

To view the data in its entirety the user would need to load each file in turn back
into Excel to combine.

9.6 Live Time Graphing Screen

The Rapidox data-logging package includes a live-time graphing facility that
allows you to monitor the progress of your data in a graphical format (see Figure

23). To access the graph check the box labelled ‘Show Graph’. The graph will
appear in a new window, and can be accessed at any time without disturbing a
run that is already in progress. You can select ‘Run’ and ‘Stop’ from the Data
Logger menu to begin and end data logging, and the window can be minimised to
(and restored from) the task bar while logging data.

To close the window and return to the main data-logging page select ‘Close Plot’
from the File menu or click on the close window button. The features of the graph
window are described below:

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Figure 23: Live-time graphing screen. The colours and labels can be edited by the user by

double clicking on them.

9.7 Main Graph Window

The graph is an XY plot, with time plotted on the X-axis, oxygen plotted on the
primary Y-axis (Y1) and pressure plotted on the secondary Y-axis (Y2). The X-axis
and the two Y-axes auto-scale during data logging so that all data points are shown
on the graph.

9.8 Plot Colours

The default colours used on the graph are set to blue for oxygen and red for
pressure which are used when the analyser is in manual mode. In auto mode a
different colour is used for each of the channels as shown in Figure 23 above. Any
of these colours can be modified to suit your preferences. To change the colours
double-click on the coloured axis label at the top of each axis. A colour palette
window will appear (see Figure 24) and a new colour can either be chosen from a
colour box, or for more variety, by clicking the ‘Define Custom Colors >>’ button.
Click on ‘OK’ to select the new colour or ‘Cancel’ to return to the graph without
change.

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Figure 24: Plot colour palette menu accessed by double-clicking on the axes titles.

9.9 Graph Titles and Labels

If you want to change the text of the graph axis labels, place the mouse pointer
over the text and do a single left click to enter edit mode. The text can then be
modified. Similarly, to change the title of the graph, place the mouse pointer over
the title and click once to edit. If you choose not to enter a title the graph will
display the path and filename of the run as the new title once the run has
finished. Note that these changes are only temporary and will be overwritten by
the defaults if a new run is started or the graph window is closed and reopened.
They are provided so that the plot may be printed with alternative labels.

9.10 Plot Co-ordinates

The box labelled ‘Plot co-ordinates’ to the upper left of the graph window displays
the actual plot co-ordinate value at the mouse pointer. This can be used to get a
quick oxygen value from the graph. Simply place the mouse pointer at a place of
interest and read the corresponding X1 and Y1 values in the box.

9.11 Last data point

During data acquisition, the box labelled ‘Last data point’ will appear at the upper
middle of the graph window. It displays the last data values read from the
analyser. The label also indicates which channel is currently being sampled e.g.
“Gas1”.

9.12 Using the Cursor

Clicking and holding the left mouse button with the pointer over the ‘C’ at the top
of the plot area activates the cursor, which appears as a vertical dashed line on the
plot. While keeping the mouse button pressed, you can now move the pointer
anywhere in the plot area or on the ‘C’ in order to move the cursor. The box
labelled ‘Cursor’ to the upper right of the graph window will display actual values
for oxygen, temperature, time and the data point number (n) at or immediately to

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the left of the cursor position. The cursor can be used to investigate actual data
values at specific points of interest on the graph.

9.13 Zooming

You can zoom in to any part of the oxygen plot by simply placing the mouse
pointer on the new graph start position and then clicking and dragging a new box
to re-size the graph. The label on the box to the upper left of the graph window
will change to ‘Zoom box co-ordinates’, and an extra set of co-ordinates, labelled
X2 and Y2, will appear, showing the co-ordinates in X and Y units of the second
corner of the zoom rectangle as you drag the mouse pointer. The plot will zoom
and auto-scale when you release the mouse button. This can be repeated if you
wish to zoom in even further. To zoom back to the original size select ‘Zoom Full’
from the View menu.

Note that although you can use the zoom facility during a live run, the graph will
auto-scale to full size with each new data point.

9.14 Y-Axis Graph Units

You can toggle the Y1 oxygen units at any time from percent to ppm and vice
versa. Select ‘O2 Units’ from the View menu and chose either percent or ppm.
The current selection is then displayed in the top right box labelled ‘O2 Axis’.

9.15 Oxygen Scale

You can display the Y1 oxygen axis in linear or logarithmic format at any time by
selecting ‘O2 Scale’ from the view menu. The current selection is then displayed in
the top right box labelled ‘O2 Axis’. Note that the zoom function is disabled when
you are viewing on a log scale.

9.16 Second Y Axis

The secondary Y axis located on the right hand side of the graph can be used to
display the pressure taken from the internal pressure sensor. The axis is linear
and auto-scaling. To select the mode of the secondary axis select ‘view’ and then
‘second axis display’. Choose from ‘none’ or ‘pressure’.

9.17 Loading an Old Run

A previously logged data file can be loaded and viewed by selecting ‘Open Data
File’ from the File menu and selecting the appropriate TXT or CSV file. A
progress bar is displayed while the data is being imported. Note that very large
data files may take several seconds to load. The data is re-graphed and you can
zoom, label axes, change colours etc., before printing the graph.

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9.18 Printing Graphs

You can print the graph at any time by selecting ‘Print Plot’ from the File menu.
This will bring up the printer dialogue box for your specific printer where you can
chose various printing options. Make sure that the printer page is set to landscape
to obtain a full size print out.

9.19 Data Logging in the Background

It is possible to begin data logging and then minimise the windows to continue
working with another application. To minimise the graph simply click on the
minimise button on the blue title bar at the top of the window. You can then use
the ALT + TAB keys to take you to other programmes already running. To return
to the graph simply maximise from the start menu bar or press ALT + TAB again.
If the graph does not redraw immediately select ‘Zoom Full’ from the View menu
to redraw.

9.20 Pausing the Data Logging

You can pause the data-logging at any time during the run by selecting the ‘data
logger’ menu and selecting ‘pause’. Repeat the action to continue, noting that the
live graph will draw a straight line between the paused points to keep continuity
of the axes. The clock keeps ticking during the pause period.

If you decide to access the menu of the Rapidox using the front keypad during
data logging, then the software will pause automatically. A message appears on
the screen informing the user that the unit is being accessed from the keypad.
Once the menu has been exited, the software will continue data logging from
where it left off.

9.21 Changing the Data Logging Parameters Mid-run

Once the data logging has begun you may change the sample interval time by
pausing the data logger and then entering a new value for the time interval. The
data logger can then be resumed with the new values in place. Note that you can
not change units (e.g. seconds to hours) once logging has started. If you originally
selected seconds then you may change the current value to a new value between 1
and 3600 seconds, if you originally selected minutes then you may change
between 0.02 and 360 and if you selected hours you may change between 0.01 and
6 hours. Note it is not possible to modify he original total length of time that the
data logging will run for once a run has commenced.

9.22 Working with Spreadsheets

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The data-logger saves data files in a standard comma separated ASCII text format
which can be readily imported into spreadsheet programmes such as MS Excel, in
order to produce plots and reports as desired. For specific information on how to
import text files into your spreadsheet programme please refer to the help guide
supplied with the programme.

Data is saved in comma separated value format, with a ‘.txt’ file extension as the
initial programme default. However, when entering the file name, you can instead
select a ‘.csv’ extension: the programme will register the last used file extension as
the new default. The ‘.csv’ extension is recognised by MS Excel, so that opening
the file will automatically run MS Excel, and this may be of benefit if your
regional decimal separator is period ‘.’ rather than comma ‘,’. However, if your
decimal separator is comma, you should continue to use the ‘.txt’ extension and
open the file explicitly from within your spreadsheet programme, defining the
field delimiter as ‘comma’ where appropriate.

9.23 Disaster Recovery

To prevent catastrophic loss of important data during a computer crash or power
failure, the data is automatically saved point by point in a temporary file called
‘Rapidox temporary data file 2100xxx.txt’, where 2100xxx is the serial number of
your Rapidox. This file is located in the same directory as the main Rapidox
programme itself and can be renamed or copied to recover data that would
otherwise be lost. Note that this file is overwritten each time ‘Run’ is selected
from the ‘Data Logger’ menu so make sure all data is recovered successfully before
starting another run.

Note that during a run using the ‘auto date stamped’ feature, the temporary data
file is wiped clean as soon as the previous data set has been saved successfully. In
the case of a crash the temporary data file should be used to recover the last day’s
worth of data that was not saved to the hard disc.

9.24 DDE Protocols

For the Rapidox software to communicate with the main oven software using DDE
please refer to the following list of possible links that are currently used:

PFCControl state: 0 = Off, 1 = Monitor Only, 2 = On
"RAPIDOX|Main!PFCControl"

Remote Data Acquisition: "RUN", "PAUSE", "RESUME", "STOP"
"RAPIDOX|Main!ACQControl"

Desired O2 level in PPM: High and Low window set as PPM_level +/- 20ppm.
Included for backwards compatibility
"RAPIDOX|Main!PPM_level"

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Desired O2 level window in PPM
"RAPIDOX|Main!HighO2SetPoint"
"RAPIDOX|Main!LowO2SetPoint"

Current O2 level in PPM
"RAPIDOX|Main!lbl_PPM_O2"
Set to -1 when not measuring, see Error state for reason, -4 to indicate sensor fault
and -5 to indicate under range error.

Current O2 Level in %
"RAPIDOX|Main!lbl_PCNT_O2"
Set to -1 when not measuring, see Error state for reason, -4 to indicate sensor fault
and -5 to indicate under range error.

Current Channel Number for Multiplexer Units
"RAPIDOX|Main!lbl_curr_mux_ch"

For Multiplexer Units the flush period remaining before alarms (and PFC)
reactivate "RAPIDOX|Main!lbl_flush_time"

Error state indication: Error ID:Description
Error ID: -5 = O2 Range Error, -4 = Sensor Fault, -3 = No available com ports, -2
= Communication problem, -1 = No analyser found, 0 = Analyser waiting, 1 =
No Error
"RAPIDOX|Main!Error"

Not used, included only for backward compatibility
"RAPIDOX|Main!lbl_ReadyIn_XXmin"

Set points for SW alarms in PPM.
"RAPIDOX|Main!Alarm1"
"RAPIDOX|Main!Alarm2"
"RAPIDOX|Main!Alarm1_Ch2"
"RAPIDOX|Main!Alarm2_Ch2"
"RAPIDOX|Main!Alarm1_Ch3"
"RAPIDOX|Main!Alarm2_Ch3"

Current alarm states: -1 = Disabled, 0 = No Alarm, 1 = Alarm
"RAPIDOX|Main!Alm1_Ch1_State"
"RAPIDOX|Main!Alm2_Ch1_State"
"RAPIDOX|Main!Alm1_Ch2_State"
"RAPIDOX|Main!Alm2_Ch2_State"
"RAPIDOX|Main!Alm1_Ch3_State"
"RAPIDOX|Main!Alm2_Ch3_State"

Current flow alarm states: -1 = Disabled, 0 = No Alarm, 1 = Alarm
"RAPIDOX|Main!Ch1_Flow_Alarm"

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"RAPIDOX|Main!Ch2_Flow_Alarm"
"RAPIDOX|Main!Ch3_Flow_Alarm"

10. Tr oubleshooting

Q: The Rapidox says 'sensor heating' for ten mins but won't begin measuring.
A: What kind of gas are you running over the sensor? Does it contain

hydrogen or helium? If so then the heater may be struggling to heat the
sensor with such cooling gas present. Does the problem go away if room air
is allowed into the analyser? Contact Cambridge Sensotec for advice. If the
message continues for around ten minutes then the analyser will give up
and indicate that the internal heater has failed and the sensor needs
replacing.

Q: The Rapidox won't power up at all.
A: There are fuses located on the power socket on both live and neutral lines.

These are standard 20mm 2A SLOW BLOW fuses available from a supplier
such as RS Components.

Q: The Rapidox gives strange readings that are way off the expected values.
A: Check to make sure which calibration gases are selected. Are they the same

as the actual gases you used to perform the calibration? If not you must
recalibrate the analyser or re-load the factory defaults to get you going
again. Also please note that when calibrating you must only use Gas inlet 1
to supply the cal gas. And disconnect any tubing from inlets 2 & 3 to
remove the risk of cross contamination if working with pressurised gases.

Q: The sensor does not read 20.9 - 21.0% in air (actual value is 20.95%).
A: If the room air is very humid, it will slightly affect the observed

measurement or the sensor may have drifted slightly because of natural
ageing. If you are using air as a calibration point then simply do a quick re­calibration in the air to compensate for this.

Q: I messed up the calibration procedure and the analyser is not working

properly.

A: Return the box to the factory defaults using the keypad or communications

software, by selecting ‘Default Configuration’ followed by ‘Write
Configuration to Analyser’ from the File menu. Now try re-calibrating the
Rapidox.

Q: The software will not talk to the Rapidox.
A: Make sure that you are using the correct cable, as supplied (pin 2 to pin 2

etc). A crossed RS232 cable (pin 2 to pin 3 etc.,) will not work. Make sure
that your COM ports are recognised by your computer. Check in your
Windows device manager to see if there are any conflicts. If you are using a
USB-Serial port adapter which does not have an FTDI chipset then you may
encounter difficulties. Contact us for advice!

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Q: I selected ‘Write to the Analyser’ and now the Rapidox is way off

calibration.

A: Only select ‘Write to the Analyser’ once all the values are correctly entered

in the boxes on the right. The best procedure is to ‘Read Analyser
Configuration’ and then press ‘Copy’ so the values in the boxes are the same
as those stored in the Rapidox memory. You can then edit these values and
then select ‘Write to the Analyser’ when finished.

Q: How do I get back to the factory calibration for my instrument.
A: Select ‘Load Configuration File’ from the File menu and look for the rxc file

on your memory stick. Select this file and then select ‘Write to the
Analyser’. This will load the factory calibration back into the Rapidox.
Alternatively you can load a standard default configuration any time using
the ‘Load Default’ option on the File menu. This configuration will not be
perfect for your analyser but will be good enough to get you started again.

10.1 Warranty

The Rapidox analyser has been carefully tested and inspected before shipment
and is guaranteed to be free from defective materials and workmanship for a
period of twelve months from date of purchase. The sensor head is replaceable
and has a life expectancy in excess of 17,500 hours. However, if the analysis gas
contains corrosive gases or large quantities of particulates, sensor life may be
shortened. In the case of the latter, it is normally possible to insert a filter prior to
the sensor head to remove the particulate material.

10.2 Conditions of Warranty:

1) This warranty is in addition to and does not affect any statutory rights of
consumer purchasers. This warranty is valid worldwide on a “back to base basis”.

2) This warranty covers breakdowns due to design or manufacturing faults; it does
not apply to damage, however caused, wear and tear, neglect, unauthorised
adjustment or repair, or any items of limited natural life.

3) In the event of failure, please take the following action:

a] Refer to the “Troubleshooting” section of your instruction manual to
identify and possibly correct the problem.

b] If the fault cannot be resolved, please contact the Cambridge Sensotec
service and repair centre at the address given on the cover of the manual.

4) The warranty period applicable shall be 12 months from the date of delivery
provided that:

a] Notice in writing of the defects complained of shall be given to Cambridge
Sensotec (The Seller) upon their appearance, and

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b] such defects shall be found to have arisen from the Seller's faulty design,
workmanship or materials, and

c] The defective goods shall be returned to the Seller's premises at the
Purchaser's expense if so requested by the Seller.

d] Any repaired or replaced goods shall be redelivered by the Seller free of
charge to the original point of delivery but otherwise in accordance with and
subject to these Conditions of Sale.

e] Alternatively the Seller shall be entitled at its absolute discretion to refund the
price of the defective goods in the event that such price shall already have been
paid by the Purchaser to the Seller, or, if such price has not been so paid, to
relieve the Purchaser of all obligation to pay the same by the issue of a credit note
in favour of the Purchaser in the amount of such price.

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11. Appendix 1: Proportional Flow Control

This appendix to the main Rapidox instruction manual describes the additional
software functions that allow proportional flow control (PFC) using a Rapidox
analyser. This is used for controlling the oxygen gas inside an oven or similar
structure by operating a proportional flow valve. A 4-20mA control signal is
generated by the Rapidox and output on the auxiliary terminals on the rear panel.
This 4-20mA signal is used to control the proportional gas valve on the oven. The
software uses established PID control theory to enable stable control of the oxygen
value, no matter how convoluted the path of the gas through to the analyser is.
The PID function requires a degree of tuning and learning once the system is up
and running to make sure the oxygen set point is stable. A badly tuned PFC could
oscillate badly or not reach the desired set point at all.

Please note that the PFC output is from Channel 1 ONLY. When the analyser is
switched to Channels 2 & 3 the PFC is temporarily disabled and the output is kept
constant until the channel becomes live again. Also there is a short delay in
control once the channel has been selected. This is to prevent any erratic
behaviour caused by the gas measurement jumping whilst the channels are in
transition. This is settable by the user (see number 36 for more details) and is
displayed on . It is recommended that Channel 1 is selected as the main
controlling channel and Channels 2 & 3 are selected only briefly as observation
points. To assist with the control the software “Config 1” page has a new option
“Gas 1 Priority” which when set to “ON” will force the multiplex to read the
channels in the following way: 1,2,1,3,1,2,1,3 and so on. In other words the PFC
channel is prioritised over channels 2 & 3. See 7.5.1 section 14) in the main text
for more details.

The additional features are ‘bolted on’ to the main software supplied with all
Rapidox analysers and the new software screens are described here. The PFC
software has an additional panel displayed as shown in Figure 25:

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Figure 25: Config 1 software tab showing additional panel displayed at the bottom. This feature

only applies to PFC versions of Rapidox.

11.1 Connections

On the rear of the H coded machines are two terminals labelled “PFC Valve 4­20mA” and “Supply Valve (In)”.

c) PFC Valve 4-20mA: These connections provide the 4-20mA signal to

control the gas valve. The signal is generated by the PID control loop
parameters entered by the user.

d) Supply Valve (In): This connection requires a 12-24V connection from the

oven to indicate when it is operation. The PFC output and the analyser
sample pump are disabled when there is no voltage signal present.

11.2 Software Description

The PFC version of the standard Rapidox software has some new tabs labelled
“PFC Control” and “SW Alarm Config”. SW stands for Software to distinguish it
from HW as in ‘HW Alarm Config’ which is the programming of the physical alarm
relays on the back of the analyser.

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11.3 Prop. Flow Control tab

Figure 26: PFC configuration page

The on-screen edit boxes below the button labelled ‘write’ contain PFC variables
that can be reprogrammed into the Rapidox. The user can choose whether to use
ppm or percent notation to edit the text boxes, where appropriate, by selecting the
‘UNITS’ menu and clicking on ‘percent’ or ‘ppm’. To access a field, either click
inside it or use the TAB key to scroll through them. The field parameters are as
follows:

28) Flushing Flow: This parameter is used to set the initial flow of gas through

the valve during the warm up cycle of the Rapidox (typically four minutes).
It is normal in this stage to have the nitrogen gas valve opened to its
maximum to allow the oxygen level to be reached as quickly as possible.
The value is entered in terms of a percentage (0-100%) where 0% means the
signal is 4mA and the valve is fully closed, and 100% means the signal is
20mA and the valve is fully open. A typical setting would be 99%, but in
this release of the software the parameter is not yet functioning so please
ignore for the time being.

29) O

2

Regulation High Point: The units of oxygen are displayed alongside the

text. Use the “Units” menu to change from % to ppm as you wish. This
parameter sets the upper limit of the target window O2 value. In order to
prevent the gas valve opening and closing excessively and wearing out, the
PFC operates around an upper and lower O2 value which defines the PFC
window. Inside the window the PFC stops adjusting the gas valve and
waits for the gas reading to creep outside the window region again. At this
point control begins again until the reading is established back inside the

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window. And so on.

30) O

2

Regulation Low Point: As described above this value sets the lower

limit of the target O2 window. Note that the low point can be set to the
same value as the high point to give maximum control around a set point,
but this is likely to cause the gas valve to “chatter”. It is normal practice to
have a window of several ppm to get best operation from the valve.

Note that the target oxygen value is always the mid-point of the window defined
in 2 & 3 above. So for example if your target oxygen value is 100ppm you may set
the upper value to 110ppm and the lower value to 90ppm. Once running the PFC
will open and close the gas valve to bring the oxygen reading down to inside the
window 90-110ppm. Once inside the window the valve is not moved any further
until the value drifts out of the window. At this point the PFC will start
controlling again to bring the reading back inside the window. The net effect is a
stable reading very close to the desired set point with minimal valve control.

31) Max Flow Control Value: This parameter allows the user to restrict the

maximum amount you can open the gas valve by in terms of a percentage
(0-100%). This is useful for damping the system if required. A value of
100% means that the valve can be allowed to open fully if so required by
the PFC.

32) Min Flow Control Value: This is the opposite parameter to 4) allowing the

user to set a minimum amount that the gas valve can be opened in terms of
a percentage 0-100%. A value of 0% means the valve can fully close if so
required by the PFC. Note that for obvious reasons the minimum value
must be smaller than the maximum value set in 4).

33) Positive Regulation Gain: This is the “P” term in PID (Proportional

Integral Differential) control. This P setting affects how the PFC behaves
when the oxygen reading is above the window setting defined in 2) and 3).
The value is entered as a positive number between 0 and 100,000 (normally
less than 10). The P term looks at the current oxygen reading and compares
it to where the desired oxygen value is. The difference in the two values is
multiplied by the P value and the resulting value is used to open and close
the gas valve. In more simple terms it is a “speed of response” factor where
a bigger value makes a big change and vice versa.

34) Negative Regulation Gain: This P setting affects how the PFC behaves

when the oxygen reading is below the window setting defined in 2) and 3).
The value is entered as a number between 0 and 100,000 (normally less
than 10) and works in exactly the same way as described in 6) above. In
most applications they are given the same value.

35) Integral Regulation Gain: This is the “I” term in PID control. The I term

is a correction factor that looks at any offset caused by the P term working
on its own and makes a correction to improve the final target oxygen value.
The value is entered as a positive number between 0 and 100,000 (normally

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less than 1).

36) Differential Regulation Gain: This is the “D” term in PID control. The D

term is a ‘damping’ factor that attempts to prevent the reading overshooting
the set-point. It is a very sensitive parameter that if incorrectly adjusted
can introduce wild oscillations in the oxygen reading. It can also be upset
by noisy oxygen readings. However when correctly set it can improve the
speed that the PFC gets to its target. The value is entered as a negative
number between 0 and -100,000 (normally between -1 & 0 but NOT actually
zero).

37) Measure Delay (s): This only applies to the multi-channel Rapidox

1100ZR3-H-PFC analyser that is fitted with a multiplexer. It introduces a
time delay (in seconds) which allows gas from channels 1/2/3 to flush away
before the PFC starts controlling once again.

38) PFC Mode: Select an option from OFF, ON or MONITOR ONLY. The

default is ON. If OFF is selected then the PFC sends a fixed 4mA to the gas
valve commanding it to stay closed. If ON is selected then the PFC is fully
operating and controlling the gas valve using all the parameters set above.
If MONITOR ONLY is set then the PFC freezes the valve in its current
position until a new mode is selected.

Once you have finished editing the parameters, select ‘Write Configuration to
Analyser’ from the file menu and the new data set will be written to the Rapidox.
The Rapidox is reprogrammed using the new configuration. The software then
reads the new settings back from the Rapidox and displays them in the boxes on
the left-hand side confirming that the configuration was successful.

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11.4 SW Alarm Config tab

Figure 27: Software Alarm Config tab

The SW (software) Alarm Config tab allows the user to set alarms in software to be
used by a DDE (dynamic data exchange). The settings here create links for the
DDE to interpret using the standard protocol as listed in section 9.24 below. For
single gas instruments such as the Rapidox 1100Z only the parameters for channel
1 are used. For the Rapidox 1100ZR3-H-PFC (multichannel) all three channels
can have software programmed alarms defined.

39) Channel 1 Alarms: Select an option from Enabled or Disabled to activate

the alarms on this channel. The default is Disabled.

40) CH1 Alarm 1 Set Point: The current units (% or ppm) are displayed by the

text and can be changed using the “Units” drop down menu. Enter a set
point for the first software alarm here. For example, for an alarm set point
at 30% O2, enter “30” into the edit box. Note that alarm 1 is triggered when
RISING above this value. The alarm condition is also data-logged as shown
in Figure 22 under the column labelled “Status” as a “0” (off) or “1” (on).

41) CH1 Alarm 2 Set Point: Enter a set point for the second software alarm

here. For example, for an alarm set point at 0.01% O2, enter “0.01” into the
edit box. Note that alarm 2 is triggered when FALLING below this value.
The alarm condition is also data-logged as shown in Figure 22 under the
column labelled “Status” as a “0” (off) or “1” (on).

If you are working with a Rapidox 1100ZR3-H-PFC with three gas inlets then

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repeat this process for the remaining channels 2 and 3.

42) Hold Channel Alarms: This only applies to the multi-channel Rapidox

1100ZR3-H-PFC analyser that is fitted with a multiplexer. If set to NO each
channel’s alarms will cancel during times that the other channels are being
sampled. To hold the alarm state during the sampling of other channels
select YES.

43) Measurement Delay (s): This only applies to the multi-channel Rapidox

1100ZR3-H-PFC analyser that is fitted with a multiplexer and introduces a
time delay in seconds to allow gas from channels 1/2/3 to flush away before
the software alarms become active again.

44) Flow Alarm Set Point (mbar): Use this parameter to set a pressure value in

mbar so that if the gas flow going into the analyser gets impeded in any way
then the pressure reading will drop below zero (i.e. the sample pump will
create a vacuum) and the low flow warning alarm will trigger below this
point. The flow alarm condition is also data-logged as shown in Figure 22
under the column labelled “Status” as a “0” (off) or “1” (on).

11.5 Data-logging with PFC

The existing Rapidox software will data-log the PFC output in the same way as
oxygen or pressure. With the PFC enabled the data-log page will look like Figure
28 with the column “PFC(%)” recording the PFC control value as a percentage
where 100% indicates the gas valve is fully open and 0% the gas valve is fully
closed:

Figure 28: PFC datalog page

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Also note that the “save to file” and “auto-date stamped files” options are both
selected by default in this version to ensure that data is always collected, saved
and stored.

The PFC signal can also be viewed on the Rapidox graph facility. Simply click on
“show plot” and the graph window will open. To display PFC signal data on the
Y2 axis select “view” and “second axis display” to click “PFC Value” as shown in
Figure 29.

Figure 29: Graph page showing how to select and display the PFC value

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®

ENT

1-Calibrate
(prompts 1)

2.095E+05ppm
(prompts 3)

Enter for two seconds to calibrate

Displays message for 1.5 seconds

Displays message for 1.5 seconds

Back to Measurements : Changes Applied

Enter for two seconds to calibrate

APPENDIX 2: MENU FLOWCHART FOR RAPIDOX 1100ZR3-H-PFC

2.095E+05ppm O2

0.0mbar

Enter for two seconds to calibrate

®

Bargraph for five seconds

3-Clean Sensor
(prompts 1)

Clean Sensor?
(prompts 4)

Cleaning Sensor

..........

ENT

®

®

Cleaning Sensor
Sensor cleaned

®

Displays message for 1.5 seconds

ENT

Calib: O2 High
(prompts 2)

®

ENT

Continues on page 2

Calib: O2 Middle
(prompts 2)

Calib: O2 Low
(prompts 2)

ENT

®

ENT

®

ENT

1.013E+03ppm
(prompts 3)

1.000E+01ppm
(prompts 3)

2.087E+05ppm O2

........

1.020E+03ppm O2

........

9.120E+00ppm O2

........

®

ENT

®

ENT

®

ENT

2.095E+05ppm O2
O2 calibrated

1.030E+03ppm O2
O2 calibrated

1.000E+01ppm O2
O2 calibrated

®

®

®

Displays message for 1.5 seconds

®

®

®

®®

Edit O2 High

Edit O2 Medium

Edit O2 Low

ESC - Back to Menu List. No changes

2-Multiplex
(prompts 1)

®

ENT

Gas 1: 30m
(prompts 2)

Mode: Auto
(prompts 2)

®

ENT

Gas 2: 10m
(prompts 2)

®

ENT

Gas 3: 1h
(prompts 2)

®

Options: 30s, 1,2,5,10,15,30m, 1,2,6,12h,OFF

Options: 30s, 1,2,5,10,15,30m, 1,2,6,12h,OFF

Options: 30s, 1,2,5,10,15,30m, 1,2,6,12h,OFF

Mode: Manual
(prompts 2)

®

ENT

Gas 1: ON
(prompts 2)

Gas 2: ON
(prompts 2)

®

ENT

Gas 3: OFF
(prompts 2)

®

®

®

ENT

ENT

G1 Priority:On
(prompts 2)

®

Options: On, Off

®

®

ENT

®

ENT

Options: On, Off Options: On, Off

Options: On, Off

G1 Priority:On
Multiplex Set

®

ENT

Displays message for 1.5 seconds

®

Displays message for 1.5 seconds

(Options: bar, psi, mbar, kPa, torr)

Displays message for 1.5 seconds

(Options: Pressure, None)

Change the value 0.1 - 1.5 s

5-Set Outputs
(prompts 1)

6-Set Units
(prompts 1)

7-Display Setup
(prompts 1)

O2 out: lin(ppm)
(prompts 6)

(Options: lin(ppm), raw mV, log(ppm))

Edit high pressure value

1.000E+01 = 0V
(prompts 3)

2.500E+05 = 10V
(prompts 3)

Edit O2(ppm)

0.000E+00 = 0V
(prompts 3)

1.250E+03 = 10V
(prompts 3)

1.250E+03 = 10V
Outputs set

Edit low pressure value

Edit O2(ppm)

Oxygen: Auto %
(prompts 6)

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(Options: Auto %, Pressure, N2 Bal %,

Exp ppm, Auto ppm)

Pressure: psi
All units set

Displays message for 1.5 seconds

Pressure: bar
(prompts 6)

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Line 2 Options
(prompts 2)

Refresh Interval
(prompts 2)

L2:Pressure
(prompts 5)

Interval: 0.3 s
(prompts 5)

L2: Pressure
Line 2 set

Interval: 0.3 s
LCD refresh set

ENT

Displays message for 1.5 seconds

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ENT ENT

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Displays message for 1.5 seconds

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Edit Ambient pressure

Mode: None
(prompts 5)

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Mode: Auto
(prompts 3)

Mode: None
Mode configured

1.000E+03mbar
(prompts 3)

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1.013E+03mbar
Pressure set

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Displays message for 1.5 seconds

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8-Pressure Mode
(prompts 1)

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Continues on page 3

Back to Menu List : Changes Applied

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Continued from page 1

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4-Set Alarms
(Prompts 1)

Set: Alarm 1
(Prompts 2)

Assign to: O2
(Prompts 2)

(Options: O2, Press)

Outputs: On
(Prompts 6)

(Options: On, Off)

Audible: On
(Prompts 6)

Visible: On
(Prompts 6)

Polarity:
(Prompts 6)

(Options: On, Off)

(Options: On, Off)

(Options:-¯)

(Options: Alarm 1, Alarm 2)

1.000E+01
(Prompts 3)

Contacts: N/O
(Prompts 6)

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Contacts: N/O
Alarms set

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Wraps around to Page 1

Enter password - default is 0000 (Options: Enable, Disable, Change)

Edit password

Enable or Disable selected

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12 - Password Menu
(Prompts 1)

Password: 0***
(prompts 3)

Password: Enable
(prompts 2)

Password: 6234
(prompts 3)

Password: Enable
PW Enabled

ENT ENT ENT

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Back to Menu List : Changes Applied

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Continued from page 2

Prompts 1:

Prompts 2:

Prompts 3: Prompts 4: Prompts 6:

ENT = OK
ESC = Back

Prompts 5:

= Change
ENT = Next
ESC = Back

= Change
ENT = OK
ESC = Back

= Change

® = Select Char.
ENT = OK
ESC = Back

= Scroll Menu
ENT = Next
ESC = Back

= Scroll Menu
ENT = Next
ESC = Exit

ESC - Back to Menu List. No changes

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11-Load Defaults
(prompts 1)

Load Defaults?
(prompts 4)

Defaults Loaded

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Displays message for 1.5 seconds

Enter for two seconds to load defaults

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(Options: 9600, 57600) Displays message for 1.5 seconds

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Baud rate: 57600
(prompts 5)

Baud rate: 57600
Baud rate set

9-Set Baud Rate
(prompts 1)

ENT ENT

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10-Set Pump Flow
(prompts 1)

Pump Flow: 90%
(prompts 5)

Pump Flow: 100%
Pump flow set

Displays message for 1.5 seconds

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(Use UP & DOWN arrows to select pump speed)

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