LogIT Black Box Manuel utilisateur
Contents
Acknowledgements 2
Introduction 3
Black Box Basics - Quick start guide 4
SmartEye sensor 6
HiTemp sensor 7
Troubleshooting 8
Introduction to Experiments 9
Black Box Experiments 10 - 39
Sensors and Cables for Black Box 40
2
Acknowledgements
Looking after Black Box
LogIT Black Box is designed as an educational tool and although durable requires a reasonable degree of care which any electronic product of this
nature needs. Never plug anything into Black Box other than official LogIT Microsense® sensors and accessories. Please read the warning guides
throughout this book and in particular do not allow Black Box to get damp, wet or expose it to extremes of temperature or shock unless instructions
specifically state. If the unit is accidentally exposed to any of these conditions it could malfunction and serious damage result.
Safety and risk assessment
It is the responsibility of the user or teacher to have made suitable risk assessments before carrying out any student led experimentation. A
teacher has a duty of care towards their students to ensure experiments are carried out within a safe environment. The instructions and
experiment ideas contained within this manual highlight particular hazards but are not exhaustive and are not a substitute for your own
assessment. Refer to your science departments risk assessment criteria and apply accordingly.
Acknowledgements and Copyright
LogIT Black Box was developed and designed in Great Britain by Steve Cousins, Mark Finch, David Palmer, Andrew Rouse and Paul Watson. The
design team express thanks and acknowledgement to their family, friends, education and commercial colleagues for their support.
This manual was written and designed by Mark Finch and David Palmer.
Contents and concepts are copyright ©2007 DCP Microdevelopments Limited. The manual may be copied by the purchasing establishment for
the educational support of LogIT Black Box provided that original copyright and product acknowledgement is retained. Any other reproduction in
whole or part is prohibited without prior written permission from the publishers. LogIT, LogIT Black Box and Microsense® are trademarks of DCP
Microdevelopments Limited. All other trademarks acknowledged.
The manual was written and designed on Apple Macintosh G5 computers using Adobe Indesign.
LogIT Black Box is designed as an educational tool. The designers and manufacturers cannot be held liable for any special, incidental,
consequential, indirect or similar damages due to loss of data, loss of business profits, business interruption or any other reason resulting from the
use of LogIT products, even if they have been advised of the possibility of such damages. Not for use in life support applications. DCP accept no
responsibility for safety or risk assessment. Statutory rights are not affected.
First Edition April 2007 Published by DCP Microdevelopments Limited, Norfolk, Great Britain. www.logitworld.com
Electromagnetic compatibility declaration
The LogIT system and accessories are designed for use as education and training
equipment. “The use of this apparatus outside the classroom, laboratory, study area or
similar such place invalidates conformity with the protection requirements of the EEC
Electromagnetic Compatibility directive (89/336/EEC) and could lead to prosecution”.
Waste electrical and electronic products must not be
disposed of with household waste.
Please recycle where facilities exist.
Check with your Local Authority or Retailer for recycling
advice.
3
Introduction to LogIT Black Box
Thank you for choosing LogIT Black Box which has been designed as an easy to use low cost datalogging solution for Science education at Secondary
and College levels.
Black Box takes advantage that most computers are now equipped with USB ports which provide both power and a high speed data link for peripherals
such as scanners, cameras etc. USB has made it possible for us to design a powerful yet low cost datalogging solution which is really compact and
easy to use, because there are no batteries, buttons or switches - your computer with the datalogging software controls everything!
Because USB is so much faster than most older traditional serial ports we have been able to build in a unique oscilloscope function enabling you to see
such fast events as sound waves or dynamics collisions live on your computer screen.
Future reliability and compatibility are assured as both the datalogging software and the firmware inside Black Box are fully upgradable using easy
downloads from the logitworld.com website.
Most Black Box sets include two versatile sensors for measuring temperature, light level and timing plus there is a wide range of over 50 other
Microsense® sensors and adapters available which are all fully compatible - just plug them in and your ready to go.
Although Black Box needs to be connected to a PC to record data, computers are now so much more affordable and compact that a powerful and
portable datalogging system can be built around a notebook computer and Black Box datalogger.
However if you need a fully self contained datalogger other LogIT models are available which record data independently without the need of a
computer such as Voyager and DataVision and the great thing is that sensors, cables and software are all compatible with each other making
classroom management of a mixture of LogIT’s easy and straightforward.
DCP is proud to have been a creator and innovator of sensing and control systems for education for over 25 years but we always welcome feedback so
that we can feed the real experience of users directly back into our product development to make future products even better.
So for free help, support or feedback any time visit www.logitworld.com or email us at [email protected]
David Palmer
DCP Microdevelopments Limited
April 2007
4
Black Box Basics
USB socket
for connecting to computer
Three colour LED’s
Each channel has a different colour which
match the graph plot colours on the
computer screen.
Sockets for LogIT
Microsense Sensors
5
Black Box Basics - Quick Start
1
∆
2
3
• Install datalogging software onto
your computer.
• Plug Black Box into a free USB port.
• The LED’s should momentarily fl ash.
• Run the datalogging software -
should automatically recognise
Black Box.
• Plug LogIT Microsense sensors
into Black Box either directly or
via an extension cable - sensors
are automatically recognised.
• Start logging!
6
SmartEye sensor
It is called SmartEye because it is a versatile light sensor which adapts automatically to either measuring light level or timing events, depending on how
you use it. SmartEye is different from a conventional light sensor in several ways:
• It has a particularly focused field of view (just 20˚) so that just like a torch you can aim and measure quite accurately. Most light level sensors have a
very wide field of view of 150˚ or more, which is reasonable for measuring the average light levels of large areas (as a camera needs) but not very good
when you are trying to measure or compare light from a specific area, as you often need to do in science experiments. You will notice that the sensor
also incorporates a shroud to shield the detector from stray or incident light.
• SmartEye measures infrared (IR) as well as visible light. Although not sensitive enough to measure the infrared radiation from a radiator for example,
it can detect stronger sources from IR remote controls or the sun and you can use this ability to demonstrate the effectiveness of different materials
such as glass as insulators or filters. This makes it a versatile sensor to have in the lab, but always remember that it is also sensitive to infrared,
particularly when measuring colours using a strong source of light like a filament lamp which has a high content of infrared light (for colorimetry you can
use the new Colorimeter unit which is specifically designed for this function).
• The detector (called a PIN photodiode) inside SmartEye is a very fast reacting device and when used with the special software contained in Black
Box it enables the sensor to be used for measuring Time, Frequency, Counts etc. You do this by simply aiming a fairly bright light (eg window or torch)
at SmartEye and passing the object you wish to time or count in between the sensor and the light source, effectively breaking the beam - this is further
explained in experiments later in this book. This extra digital functionality is selected by the software you are using.
The distance SmartEye can be used away from Black Box can be extended using one of the Microsense extension cables but we recommend it is not
extended beyond 3 metres as this may introduce interference or inaccuracies.
The SmartEye sensor reads directly in the range of 0 to 20,000 Lux, the standard SI unit of Light illuminance. Although this is a very wide range, on an
extremely bright sunny day the sensor can have too much light. But just as with human eyes, the level can be reduced using a filter (or sunglasses) to
cut down the light. Note that although it may be tempting to point the sensor straight at a source of light this is not generally good practice and could
cause serious damage if pointed at the sun. So, just as a photographer does with a light meter, the light sensor should be pointed at a surface or
‘target’ so that you measure the reflected light - a white card is ideal.
Care
This sensor is robust but take care to protect it from excessive heat or light and never point any sensor directly at the sun. It is not waterproof so protect
from water, rain or high moisture.
Alternative sensors (also see page 40)
Other light level measuring sensors include the LUX sensor (which has eye response) and SPX LUX (very wide 100,000 Lux range).
Alternative sensors for time and speed measurements include Light gate, Reflective switch, Accelerometer and Ultrasonic Ranger sensors.
7
HiTemp temperature sensor
HiTemp is a general purpose temperature probe designed for measuring air, liquids (but not acids) and skin temperature within the range of -10°C to +
110°C with a 0.1°C resolution and a typical accuracy of better than 1˚C.
Due to its small size and low thermal mass, HiTemp has a fast response time and the sensor and cable are both lightweight and waterproof making it
suitable for suspending in air or liquid and also ideal for measuring low surface or skin temperatures with it’s small tip.
As with any sensor, if you need to measure with accuracy and repeatability you must carefully control the experiment conditions and consider the effect
of where and how the sensor is positioned. For example, if it is put into a beaker the sensor should not touch the glass walls and the liquid should be
repeatedly agitated to maintain even heat transfer around the sensor.
The distance HiTemp can be used away from Black Box can be extended using one of the Microsense extension cables but we recommend it is not
extended beyond 3 metres as this may introduce interference or inaccuracies.
Care
The HiTemp tip and cable are waterproof but the connecting plug (and socket) are not. The sensor uses a thin cable to make it very flexible and
versatile but you need to take care that the cable is not pulled, twisted or bent sharply as this could fracture wires inside - we suggest it is treated with
the same care as you would the flexible wires used for music player headphones. Also take care not to force the sensor into things like hard soil and
never expose it to strong acids or alkalis which could attack the plastic or stainless steel tip.
Do not expose the sensor to temperatures outside of its range - for example take special care if measuring the temperature in a heated pot or kettle
as the element is at a much higher temperature than the water and will damage the sensor if touched. HiTemp is not suitable for measuring the
temperature of anything over 110˚C maximum, including flames.
Alternative sensors (also see page 40)
For frequent experiments more suited to a longer solid probe style and which do not require such fast response times we suggest the LogIT
Microsense® ProTemp which has a strong 180mm long stainless steel probe and which can measure a wider span of temperature in the -30 to +130˚C
range with a 0.5˚ accuracy and 0.1˚ resolution. The ProTemp can plug directly into Black Box for hand held wire-free monitoring and can also be used
further away by using a sensor extension lead.
For higher temperature ranges such as ovens or even flames, a K-type thermocouple adapter is available which works with most of the different
styles of K-type thermocouples available and can measure temperatures from -50˚C to +1200˚C with a resolution of 1˚C, although bear in mind that
thermocouples are generally not as accurate as the precision thermistor devices used in HiTemp and ProTemp.
8
Troubleshooting
Problem
I have purchased a new sensor but it is not recognised by the
datalogging software.
I already have LogIT datalogging software installed on my computer
but this does not seem to work with my new Black Box datalogger.
My Black box does not seem to always work reliably.
When I plug Black Box into my computer with no sensors connected
the red light on channel 1 comes on but nothing else happens.
I need help using my Black Box.
Solution
Update your datalogging software by checking www.logitworld.com
or the datalogging software publishers website.
Install new software using the CD supplied with Black Box or check
with your existing datalogging software publisher to see if there is an
update available.
Check you do not have other software running at the same time
which may conflict with its operation - also check your computer
has enough power to run Black Box from the USB socket you are
using - some USB ports can provide more power than others (check
computer manual).
Reinstall the firmware inside Black Box using ‘Update loggers
system software’ in LogIT Lab.
24 hour information and support : www.logitworld.com
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