RTI Cobia User manual

Reference Manual - English - v2016.12A
Cobia
RTI article number: 4760.001206

Welcome to the Cobia
The Cobia is an X-ray Analyser/Multimeter for
everybody working with Quality Assurance and
Service of X-ray systems.

Version 2016.12A
NOTICE
Microsoft, Windows, Win32, Windows 7, Windows 8, and Windows 10 are either registered
trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.
BLUETOOTH is a trademark owned by Bluetooth SIG, Inc., USA.
Notice
RTI Electronics Inc.
33 Jacksonville Road, Bldg. 1,
Towaco, NJ 07082,
USA
Phone: [phone] (Toll free)
Int. [phone]
Fax: Int. [phone]
E-mail
Sales: [e-mail]
Support: [e-mail]
Service: [e-mail]
Contact Information -
United States
RTI Group AB reserves all rights to make changes in the Cobia and the
information in this document without prior notice.
RTI Group AB assumes no responsibility for any errors or consequential
damages that may result from the use or misinterpretation of any information
contained in this document.
Copyright © 2014-2016 by RTI Group AB. All rights reserved.
Content of this document may not be reproduced for any other purpose than
supporting the use of the product without prior permission from RTI Group AB.
RTI Group AB
Flöjelbergsgatan 8 C
SE-431 37 MÖLNDAL
Sweden
Phone: Int. [phone]
E-mail
Sales: [e-mail]
Support: [e-mail]
Service: [e-mail]
Contact Information -
World Headquarters
http://www.rtigroup.comWeb site: Web site: http://www.rtigroup.com
III
Cobia - Reference Manual

Cobia - Reference Manual
Intended Use of the Cobia System
Accessory to diagnostic X-ray equipment to be used as an electrometer. Together with external
probes it is to be used for independent service and quality control, as well as measurements of
kerma, kerma rate, kVp, tube current, exposure time, luminance, and illuminance within limitations
stated below.
If installed according to accompanying documents, the product is intended to be used together
with all diagnostic X-ray equipment except for:
- therapeutical X-ray sources.
- X-ray equipment with tube potential below 18 kV.
- X-ray equipment on which the instrument cannot be mounted properly, e.g. equipment where the
beam field size is narrower than the active part of the detector.
- specific types of X-ray equipment listed in the instructions for use or in additional information
from the manufacturer.
With the X-ray installation in stand-by conditions without patients present, the product is intended
to be used:
- to provide the operator with information on radiation beam parameters that might influence
further steps in an examination but not an ongoing exposure.
- for assessing the performance of the X-ray equipment.
- for evaluation of examination techniques and procedures.
- for service and maintenance measurements.
- for quality control measurements.
- for educational purposes, authority supervision etc.
The product is intended to be used by hospital physicists, X-ray engineers, manufacturer's service
teams, and other professionals with similar tasks and competencies. The operator needs a short
training to be able to use the product as intended. This training can be achieved either by careful
study of the manual, studies of the built-in help function in measurement software or, on request,
in a short course ordered from the manufacturer.
The product is intended to be used inside X-ray rooms ready for clinical use and can safely be left
switched on and in any measuring mode in the vicinity of patients.
The product is NOT intended to be used:
- for direct control of diagnostic X-ray equipment performance during irradiation of a patient.
- so that patients or other unqualified persons can change settings of operating parameters during
and immediately before and after measurements.
In Germany, the Cobia can also be used for dose measurements in the context of legal metrology
(see the German user manual for more information).
Intended Use
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Contents
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Table of Contents
1. ..................................................................................................... 4Introduction
.................................................................................................................. 41.1 About this Manual
.................................................................................................................. 41.2 Introduction to the Cobia
.................................................................................................................. 51.3 Computer Requirements
2. ..................................................................................................... 7Description of the Cobia
.................................................................................................................. 72.1 Product Overview
..................................................................................................................102.1.1 User Interface
..........................................................................................................102.1.1.1 Screen Description
..........................................................................................................122.1.1.2 Screen Indicators
..........................................................................................................152.1.1.3 Menu Overview
..........................................................................................................162.1.1.4 Keyboard Operation
..........................................................................................................162.1.1.5 Previous Measurements
.................................................................................................................. 172.2 Setting Up the Cobia for the First Time
.................................................................................................................. 172.3 Getting Started
..................................................................................................................172.3.1 Before Starting the Cobia for the First Time
..................................................................................................................182.3.2 Charging the Battery
.................................................................................................................. 192.4 Performing a Measurement
..................................................................................................................192.4.1 Measuring with the Internal Detector
..................................................................................................................212.4.2 Measuring with a General External Detector
..................................................................................................................222.4.3 Measuring with a Light Probe
..................................................................................................................222.4.4 Measuring with the Optional Internal MAS
..........................................................................................................232.4.4.1 Connecting the MAS Cable
..........................................................................................................242.4.4.2 Tube Current Safety Precautions
..................................................................................................................252.4.5 Measurement Settings
..................................................................................................................272.4.6 Error & Display Messages
.................................................................................................................. 292.5 Hardware and Specifications
..................................................................................................................302.5.1 Parameter IDs
..................................................................................................................312.5.2 Cobia Internal
..........................................................................................................312.5.2.1 General ..........................................................................................................322.5.2.2 Power & Communication Specifications
..........................................................................................................332.5.2.3 Specifications, Cobia
..........................................................................................................372.5.2.4 Typical Response, Cobia
..........................................................................................................382.5.2.5 Manual Energy Correction, Cobia
..................................................................................................................402.5.3 Cobia External Probes
.................................................................................................................. 442.6 Cobia Communication Protocol
..................................................................................................................442.6.1 General
..................................................................................................................452.6.2 Use Cases
..................................................................................................................452.6.3 Requirements
..................................................................................................................462.6.4 Command Structure
..................................................................................................................462.6.5 Reply Protocol, Simple
..................................................................................................................462.6.6 Reply Protocol, Multi-line
..................................................................................................................472.6.7 Parameter IDs
..................................................................................................................472.6.8 Reply Protocol, Errors
..................................................................................................................492.6.9 List of Commands

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..................................................................................................................532.6.10 Cobia Start-Up
..................................................................................................................532.6.11 CRC-Calculation
..................................................................................................................542.6.12 Examples of Communication
.................................................................................................................. 552.7 Standards and Compliances
..................................................................................................................552.7.1 Waste Electrical and Electronic Equipment (WEEE)
..................................................................................................................552.7.2 Waste Batteries and Accumulators
..................................................................................................................572.7.3 Manufacturer's Declaration of Conformity
..................................................................................................................582.7.4 Intended Use
..................................................................................................................592.7.5 FCC Certification
..................................................................................................................592.7.6 German Measurement and Verification Act (PTB Type Certificate)
.................................................................................................................. 602.8 Maintenance
..................................................................................................................602.8.1 Scheduled Calibration
..................................................................................................................612.8.2 Updating the System
..................................................................................................................622.8.3 Changing the Battery
3. ..................................................................................................... 64Measurement Principles & Theory
.................................................................................................................. 643.1 Waveforms and Triggers
.................................................................................................................. 663.2 Measurement Principle for the Cobia
.................................................................................................................. 673.3 Linearity
.................................................................................................................. 683.4 Reproducibility
4. ..................................................................................................... 70Problems and Solutions
.................................................................................................................. 704.1 Troubleshooting
.................................................................................................................. 714.2 Bluetooth
..................................................................................................................714.2.1 Bluetooth Passkey
.................................................................................................................. 714.3 How To Report a Problem
5. ..................................................................................................... 73Glossary
............................................................................................................. 74Index

Introduction
Chapter 1

Cobia - Reference Manual
1. Introduction
About this Manual
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1 Introduction
About this Manual1.1
This manual is divided into a few main parts.
1. A general description of the Cobia.
2. Some theoretical background and basic principles.
3. Descriptions on performing measurements with the system for different
modalities.
4. Troubleshooting tips and a glossary.
Users who use the Cobia with only a PC and Ocean 2014 are recommended to read at
least the following topics:
Introduction
Description of the Cobia
Measurements with the Cobia System
For the Cobia system, calibration data is stored inside the system.
Typographical Rules
Terms in bold face are references to texts on screenshots, like buttons and texts, and
menu items. Other special terms are italicized.
Introduction to the Cobia1.2
Congratulations to your purchase of a Cobia. You have now in your hand the most
user-friendly tool for X-ray analysis. It has been carefully designed to meet the needs
of both standard QA applications as well as advanced service/repair/calibration of
modern X-ray systems, while still being very simple and intuitive to use. Depending on
model, it can measure all the required parameters such as kVp, exposure time, dose,
HVL, Total Filtration, dose/pulse, dose rate, tube current, mAs, waveforms, and much
more.
To get to know your specific Cobia model, please read the User Manual that was
included with your meter. That manual is available in numerous languages.
This manual covers all models of the Cobia. An overview table of the capabilities of
the different models are given in section General .
The Cobia can be used in different ways:
All models can be used as a "meter" with the built-in display.
Some models can be used as a complete "QA-system" together with a PC and
the Ocean 2014 software.
Some models can be used as a measurement device for connecting and
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Introduction to the Cobia
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obtaining data into your own software (using specified communication protocol)
This manual describes the Cobia by itself. The PC software, Ocean 2014, is described
in a separate manual.
The Cobia system's main features are:
Very easy and intuitive to use
Accurate
Active Compensation - No manual corrections are needed
Automatic measuring modes for pulsed waveforms
Compact
USB and Bluetooth interface (some models)
Free upgrade of firmware
New and unique design
Free upgrades of the firmware (the software resident in the cabinet and measuring
modules) are available on RTI Web site at http://www.rtigroup.com.
If you have questions, comments, or feel that some functionality is missing, you are
welcome to contact us at RTI at [e-mail]. You can of course also call or
send a fax (see notice section for details).
Computer Requirements1.3
To run the Ocean 2014 Windows software, there are some requirements. Please see the Ocean
2014 manual for details.
In normal case when the Cobia runs standalone, no computer is required. But if the system of
the Cobia shall be updated, a special part of the Cobia that is called Cobia Updater is used. This
Cobia Updater requires a computer with the following requirements:
Minimum requirements
Computer with USB port, with support for USB mass storage devices (sometimes called USB
stick or USB memory)
Examples: Windows XP or newer (32-bit, or 64-bit), Apple Mac OS/X, Linux, etc.

Description of the Cobia
Chapter 2

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2. Description of the Cobia
Product Overview
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2 Description of the Cobia
Product Overview2.1
The Cobia comes in a lot of different models, the external design is basically the same
for all models (except for the External Probe port).
TOP VIEW
BOTTOM VIEW

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#
Name
Description
1
Display
Cobia display. See section Screen Description
2
Up arrow
button
Used to move up in the user interface. See section Keyboard
Operation
3
Down arrow
button
Used to move down in the user interface. See section Keyboard
Operation
4
Left arrow
button
Used to move left/back in the user interface. See section
Keyboard Operation
5
Right arrow
button
Used to move right or make a selection in the user interface.
See section Keyboard Operation
6
Menu and On/
Off button
Used to start and power off the Cobia, and display the system
menu. See section Keyboard Operation
7
Positioning
marker
Marks the position of the radiation detector's active volume
below the measurement surface.
8
Measurement
surface
Circular entrance surface for the measurement sensors (some
models only)
9
Status indicator
Indicates functional status of the Cobia. It flashes during
system start-up and lights up when there is a signal triggering
the measurement system
10
External
detector input
Used to attach external measurement detectors or probes
(some models only)
11
Battery
charging
indicator
The orange battery charging indicator is lit when the battery is
charging. See section Battery Charging Details . Note that
charging is possible even when the unit is off
12
Optional MAS
connector
Used to attach invasive MAS cable (selected models). See
section Connecting the MAS Cable
13
Micro-USB
connector
Used both to charge and to connect the Cobia to a computer.
See sections Charging the Battery , Updating the System
, and Communicating with a PC
14
Measurement
center marking
Marks the center position of the radiation measurement on
the bottom side
15
Product label
Displays detailed information about the product and model (on
the bottom side)
16
Reset hole
Used to do a hardware reset of the Cobia. Marked "RST"(on
the bottom side)
10
16
16
16
16
16
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The USB port is used when using Cobia Updater to update the internal firmware. It
can also be used when the Cobia Flex or Cobia Sense PC is used together with a PC
running the QA software Ocean 2014. The system is then powered from the PC via
the USB cable. The PC however have a limited USB power output, so when fast
charging is needed the power supply needs to be connected here. This is also possible
when using the Bluetooth link to communicate with a computer. The port is marked
with the USB symbol ( ).
Below block diagrams of the different Cobia models are shown.

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Product Overview
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2.1.1 User Interface
2.1.1.1 Screen Description
Single view
List view
Menu view
A status field is displayed at the top of the screen. The left side of the field shows the
Radiation or Measurement Quality Code and a description of the active range (1). The
middle part of the field displays icons for when an external detector and/or internal
MAS cable is attached as well as warning symbols for when any settings are set to
non-standard values (2). The right side of the field displays an icon for power supply
and an indicator for the battery level (3). See section Screen Indicators for details.
A simple user guide is displayed at the bottom of the screen. For each view, the
buttons that are functional in this view are shown, together with a short text or
symbol describing the function of the buttons (4-6).
Single view
In the Single view, only one active parameter is
displayed, represented by the value and its unit.
Each unit is shown by a specific color. Pressing the
up/down arrow buttons / will change the
active parameter.
When using the internal tube current socket (MAS)
or an external detector (EXT), a
corresponding indicator will appear in the leftmost side of the unit field (not shown).
Note! The shown parameters may vary depending on the model of the Cobia. The
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example picture shows a tube voltage measurement with Cobia Flex R/F kV & Dose.
Located to the left of the value, two symbols may be visible:
1A. A play symbol (triangle) is visible during the measurement.
It is filled (green) during the radiation detection, and will then
stay contoured while the Cobia accepts continued
measurement during the Restart Delay.
1B. When using the optional parameter cycling, a rotating
indicator will appear just above the play symbol when the
cycling is in progress.
2. A pulse indicator is shown below the play symbol. This
indicator is turned on when pulses are detected, resulting in
the display of additional pulse parameters.
List view
In the List view, all the available parameters are
shown simultaneously. The active parameter
(displayed in the Single view) is indicated in color.
If a measurement is started when the Cobia is in
the List view, the display will switch to the Single
view during the measurement
and then return to the List view after completion. For models with external input,
parameters from MAS or EXT are marked accordingly.
Note! The available parameters may vary depending on the model of the Cobia and
attached detectors. The example picture shows a pulsed measurement with Cobia
Flex R/F kV & Dose.
Main Menu view
The Menu view displays a set of available
functions, selected by pressing the right arrow
button . Reset Measurement zeroes and resets
the measurement. Prev. Measurements recalls the
results of earlier measurements (see section
Previous Measurements for a detailed
description).
Settings is for viewing and modifying the
measurement settings. Preferences is for
viewing and adjusting personal preferences. Any setting change that can affect the
measurement results will be shown in the status field (top of screen). System Info
gives detailed information about the Cobia, needed during support. Power Off turns
the Cobia off. When using an external detector or probe, there will be an extra menu
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Product Overview
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item, Ext.Detector, that displays detector information and settings as described
below. See section Menu Description for a graphical overview.
Select External Detector Calibration
When an external detector containing more than
one calibration is connected to the Cobia, a
selection screen will be shown (left).
For later calibration changes, the selection screen
is also available via the Menu .
2.1.1.2 Screen Indicators
Below is an overview of all on-screen symbols and what they mean.
See also section Error & Display Messages for details relating to the measurement
results.
Top Of Screen Status Icons
The external power supply is attached (fast charging).
The Cobia is powered from a PC via USB (or non-compliant power supply).
An external detector is attached to the EXT connector (some models).
An external MAS cable is attached to the MAS connector (some models).
Both external detector and MAS cable are attached.
The user has changed measurement settings that can affect the result.
The user has selected AMX-4 kV setting.
The user has selected Auto tube voltage setting.
The user has selected PPV tube voltage setting.
A measurement value was measured with reduced accuracy, but can be
manually corrected for normal accuracy (see Manual Energy Correction,
Cobia or the RTI Dose Probe manual).
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Trig and Screen Cycling Indicators
The system has trigged and is actively collecting data.
The system has trigged off and is ready to continue the same measurement
(Restart delay is running).
The system is still ready to continue the same measurement (Restart delay
is running), but it has started the parameter cycling, indicated by a rotating
symbol.
The system has ended the measurement and cannot continue the same
measurement (Restart delay is over), but it continues with the parameter
cycling, indicated by the rotating symbol.
The system has ended the measurement and the parameter cycling.
Pulse Indicator
To the left of the measurement figures on the single view screen, a symbol
is lit when the Cobia detects at least 3 pulses in the waveform.
Signal Source Indicator
To the left of the unit field on the single view screen and to the left of each parameter
data on the List view screen, a symbol will indicate the source of the parameter.
Cobia If no symbol is shown, the parameter originates from the internal detector.
The parameter is measured from the detector attached to the EXT input.
The parameter is measured from the detector attached to the MAS input.

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Unit Symbols
Symbol for pulse, for instance dose per pulse.
Symbol for pulse width (parameter P11).
Symbol for duty cycle (parameter P12). In pulsed waveform the
percentage the waveform is above 50 % per cycle.
Symbol for effective time (parameter P13). For a pulsed
waveform the total time the waveform is above 50 %.
Symbol for number of pulses (parameter P7). For a pulsed
waveform the total number of pulses/frames in the waveform.

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2.1.1.3 Menu Overview

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For a Cobia where an external detector is attached, another menu item will appear.
There you can read the data for that detector and change radiation quality (if more
than one are available).
2.1.1.4 Keyboard Operation
Menu and On/Off button
If Power = Off: Press once to start the Cobia
If Power = On: Press once to display the menu. Press and hold to switch off
the Cobia
In Menu view: Closes the menu
Up and Down arrow buttons
In Single view: Changes the active parameter shown
In List view: Changes the highlighted (active) parameter
In Menu view: Moves the marker
Right arrow button
In Single view: Switches the display to the List view
In Menu view: Activates the marked menu item
In the Settings or Preferences menus: Changes the set value (displayed in
yellow) or activates the menu item
Left arrow button
In List view: Switches the display back to the Single view
In Menu view: switches the display back to the previous menu or screen
2.1.1.5 Previous Measurements
On the main menu you can access your old measurement data.
The function displays the 7 last sessions containing up to 99 measurements per
session.
Every time the Cobia is started a new session is created, unless the last session was
empty (no empty sessions). The oldest session is then automatically deleted.
Every time you perform a measurement the measurement is automatically saved.
This is done after the Restart delay, i.e. when the triangle disappears.
For light measurements, however, there is a special save button.
The details of viewing a previous measurement is given below.