TiePie Handyscope TP450 User manual

Handyscope TP450
User manual
TiePie engineering

ATTENTION!
Measuring directly on the line voltage can be very dangerous.
Copyright c 2018 TiePie engineering.
All rights reserved.
Revision 2.21, June 2018
Despite the care taken for the compilation of this
user manual, TiePie engineering can not be held
responsible for any damage resulting from errors
that may appear in this manual.

Contents
1 Safety 1
2 Declaration of conformity 3
3 Introduction 5
3.1 Differential input .................... 6
3.1.1 Differential test lead .............. 7
3.2 Sampling ........................ 8
3.3 Sample frequency .................... 9
3.3.1 Aliasing ..................... 10
3.4 Digitizing ........................ 11
3.5 Signal coupling ..................... 12
4 Driver installation 15
4.1 Introduction ....................... 15
4.2 Where to find the driver setup ............ 15
4.3 Executing the installation utility ........... 15
5 Hardware installation 21
5.1 Power the instrument ................. 21
5.2 Connect the instrument to the computer ....... 21
5.2.1 Found New Hardware Wizard ......... 22
5.3 Plug into a different USB port ............ 22
6 Input connnectors 23
6.1 Using the Measure lead TP-C812C .......... 23
7 Specifications 25
7.1 Acquisition system ................... 25
7.2 Input CH1 ........................ 25
7.3 Trigger system ..................... 26
7.4 Interface ......................... 26
7.5 Power .......................... 26
7.6 Physical ......................... 26
7.7 I/O connectors ..................... 26
7.8 System requirements .................. 27
7.9 Environmental conditions ............... 27
7.10 Certifications and Compliances ............ 27
Contents I

7.11 Measure lead ...................... 27
7.12 Package contents .................... 28
II

Safety 1
When working with electricity, no instrument can guaran-
tee complete safety. It is the responsibility of the person
who works with the instrument to operate it in a safe way.
Maximum security is achieved by selecting the proper in-
struments and following safe working procedures. Safe
working tips are given below:
•Always work according (local) regulations.
•Work on installations with voltages higher than 25 VAC or
60 VDC should only be performed by qualified personnel.
•Avoid working alone.
•Observe all indications on the Handyscope TP450 before con-
necting any wiring
•Check the probes/test leads for damages. Do not use them
if they are damaged
•Take care when measuring at voltages higher than 25 VAC or
60 VDC.
•Do not operate the equipment in an explosive atmosphere or
in the presence of flammable gases or fumes.
•Do not use the equipment if it does not operate properly.
Have the equipment inspected by qualified service personal.
If necessary, return the equipment to TiePie engineering for
service and repair to ensure that safety features are main-
tained.
Safety 1

2Chapter 1

Declaration of conformity 2
TiePie engineering
Koperslagersstraat 37
8601 WL Sneek
The Netherlands
EC Declaration of conformity
We declare, on our own responsibility, that the product
Handyscope TP450-250(XM)
Handyscope TP450-50(XM)
for which this declaration is valid, is in compliance with
EN 55011:2009/A1:2010 IEC 61000-6-1/EN 61000-6-1:2007
EN 55022:2006/A1:2007 IEC 61000-6-3/EN 61000-6-3:2007
according the conditions of the EMC standard 2004/108/EC,
also with
Canada: ICES-001:2004 Australia/New Zealand: AS/NZS
and
IEC 61010-1:2001/EN USA: UL61010-1: 2004
and is categorized as CAT II 600 Vrms, 800 Vpk, 800 Vdc
Sneek, 1-11-2017
ir. A.P.W.M. Poelsma
Declaration of conformity 3

Environmental considerations
This section provides information about the environmental impact
of the Handyscope TP450.
Handyscope TP450 end-of-life handling
Production of the Handyscope TP450 required the extraction and
use of natural resources. The equipment may contain substances
that could be harmful to the environment or human health if im-
properly handled at the Handyscope TP450’s end of life.
In order to avoid release of such substances into the environment
and to reduce the use of natural resources, recycle the Handyscope
TP450 in an appropriate system that will ensure that most of the
materials are reused or recycled appropriately.
The symbol shown below indicates that the Handyscope TP450
complies with the European Union’s requirements according to Di-
rective 2002/96/EC on waste electrical and electronic equipment
(WEEE).
Restriction of Hazardous Substances
The Handyscope TP450 has been classified as Monitoring and Con-
trol equipment, and is outside the scope of the 2002/95/EC RoHS
Directive.
4Chapter 2

Introduction 3
Before using the Handyscope TP450 first read chapter 1
about safety.
Many technicians investigate electrical signals. Though the
measurement may not be electrical, the physical variable is of-
ten converted to an electrical signal, with a special transducer.
Common transducers are accelerometers, pressure probes, current
clamps and temperature probes. The advantages of converting the
physical parameters to electrical signals are large, since many in-
struments for examining electrical signals are available.
The Handyscope TP450 is a single channel, 16 bits measuring
instrument with galvanically isolated differential input with high
input range. It is available in two models with different maximum
sampling and streaming rates:
Maximum sampling rate Model 250 Model 50
Block mode 250 kS/s 50 kS/s
Streaming mode 250 kS/s 50 kS/s
Table 3.1: Maximum sampling rates
The Handyscope TP450 is available with two memory configura-
tions, these are:
Memory Model 250 Model 50
Standard model 16 KiS 16 KiS
Option XM 1 MiS 1 MiS
Table 3.2: Maximum record length per channel
With the accompanying software the Handyscope TP450 can be
used as an oscilloscope, a spectrum analyzer, a true RMS voltmeter
or a transient recorder. All instruments measure by sampling the
input signals, digitizing the values, process them, save them and
display them.
Introduction 5

3.1 Differential input
Most oscilloscopes are equipped with standard, single ended inputs,
which are referenced to ground. This means that one side of the
input is always connected to ground and the other side to the point
of interest in the circuit under test.
Figure 3.1: Single ended input
Therefore the voltage that is measured with an oscilloscope with
standard, single ended inputs is always measured between that
specific point and ground.
When the voltage is not referenced to ground, connecting a
standard single ended oscilloscope input to the two points would
create a short circuit between one of the points and ground, possi-
bly damaging the circuit and the oscilloscope.
A safe way would be to measure the voltage at one of the two
points, in reference to ground and at the other point, in reference to
ground and then calculate the voltage difference between the two
points. On most oscilloscopes this can be done by connecting one
of the channels to one point and another channel to the other point
and then use the math function CH1 - CH2 in the oscilloscope to
display the actual voltage difference.
There are some disadvantages to this method:
•a short circuit to ground can be created when an input is
wrongly connected
•to measure one signal, two channels are occupied
•by using two channels, the measurement error is increased,
the errors made on each channel will be combined, resulting
in a larger total measurement error
•The Common Mode Rejection Ratio (CMRR) of this method
is relatively low. If both points have a relative high voltage,
but the voltage difference between the two points is small,
6Chapter 3

the voltage difference can only be measured in a high input
range, resulting in a low resolution
A much better way is to use an oscilloscope with a differential
input.
Figure 3.2: Differential input
A differential input is not referenced to ground, but both sides
of the input are ”floating”. It is therefore possible to connect one
side of the input to one point in the circuit and the other side of
the input to the other point in the circuit and measure the voltage
difference directly.
Advantages of a differential input:
•No risk of creating a short circuit to ground
•Only one channel is required to measure the signal
•More accurate measurements, since only one channel intro-
duces a measurement error
•The CMRR of a differential input is high. If both points have
a relative high voltage, but the voltage difference between the
two points is small, the voltage difference can be measured
in a low input range, resulting in a high resolution
The Handyscope TP450 is galvanically isolated. This means
that there is no electrical connection between the inputs and the
USB connection. It is therefore not possible to damage the con-
nected computer when (accidentally) making a wrong connection.
3.1.1 Differential test lead
The Handyscope TP450 comes with a special differential test lead.
This test lead is specially designed to ensure a good CMRR.
Introduction 7

The special heat resistant differential test lead provided with
the Handyscope TP450 is designed to be immune for noise from
the surrounding environment.
3.2 Sampling
When sampling the input signal, samples are taken at fixed inter-
vals. At these intervals, the size of the input signal is converted to a
number. The accuracy of this number depends on the resolution of
the instrument. The higher the resolution, the smaller the voltage
steps in which the input range of the instrument is divided. The
acquired numbers can be used for various purposes, e.g. to create
a graph.
Figure 3.3: Sampling
The sine wave in figure 3.3 is sampled at the dot positions. By
connecting the adjacent samples, the original signal can be recon-
structed from the samples. You can see the result in figure 3.4.
8Chapter 3

Figure 3.4: ”connecting” the samples
3.3 Sample frequency
The rate at which the samples are taken is called the sampling
frequency, the number of samples per second. A higher sampling
frequency corresponds to a shorter interval between the samples.
As is visible in figure 3.5, with a higher sampling frequency, the
original signal can be reconstructed much better from the measured
samples.
Figure 3.5: The effect of the sampling frequency
The sampling frequency must be higher than 2 times the high-
est frequency in the input signal. This is called the Nyquist fre-
quency. Theoretically it is possible to reconstruct the input signal
with more than 2 samples per period. In practice, 10 to 20 sam-
Introduction 9

ples per period are recommended to be able to examine the signal
thoroughly.
3.3.1 Aliasing
When sampling an analog signal with a certain sampling frequency,
signals appear in the output with frequencies equal to the sum and
difference of the signal frequency and multiples of the sampling
frequency. For example, when the sampling frequency is 1000 Hz
and the signal frequency is 1250 Hz, the following signal frequencies
will be present in the output data:
Multiple of sampling frequency 1250 Hz signal -1250 Hz signal
...
-1000 -1000 + 1250 = 250 -1000 - 1250 = -2250
0 0 + 1250 = 1250 0 - 1250 = -1250
1000 1000 + 1250 = 2250 1000 - 1250 = -250
2000 2000 + 1250 = 3250 2000 - 1250 = 750
...
Table 3.3: Aliasing
As stated before, when sampling a signal, only frequencies lower
than half the sampling frequency can be reconstructed. In this
case the sampling frequency is 1000 Hz, so we can we only observe
signals with a frequency ranging from 0 to 500 Hz. This means
that from the resulting frequencies in the table, we can only see
the 250 Hz signal in the sampled data. This signal is called an
alias of the original signal.
If the sampling frequency is lower than twice the frequency of
the input signal, aliasing will occur. The following illustration
shows what happens.
10 Chapter 3

Figure 3.6: Aliasing
In figure 3.6, the green input signal (top) is a triangular signal
with a frequency of 1.25 kHz. The signal is sampled with a fre-
quency of 1 kHz. The corresponding sampling interval is 1/1000Hz
= 1ms. The positions at which the signal is sampled are depicted
with the blue dots. The red dotted signal (bottom) is the result
of the reconstruction. The period time of this triangular signal
appears to be 4 ms, which corresponds to an apparent frequency
(alias) of 250 Hz (1.25 kHz - 1 kHz).
To avoid aliasing, always start measuring at the highest sam-
pling frequency and lower the sampling frequency if required.
3.4 Digitizing
When digitizing the samples, the voltage at each sample time is
converted to a number. This is done by comparing the voltage
with a number of levels. The resulting number is the number cor-
responding to the level that is closest to the voltage. The number
of levels is determined by the resolution, according to the following
relation: LevelCount = 2Resolution .
Introduction 11

The higher the resolution, the more levels are available and
the more accurate the input signal can be reconstructed. In figure
3.7, the same signal is digitized, using two different amounts of
levels: 16 (4-bit) and 64 (6-bit).
Figure 3.7: The effect of the resolution
The Handyscope TP450 measures at 16 bit resolution (216=65536
levels). The smallest detectable voltage step depends on the input
range. This voltage can be calculated as:
V oltageStep =F ullInputRange/LevelCount
For example, the 2 V range ranges from -2 V to +2 V, therefore
the full range is 4 V. This results in a smallest detectable voltage
step of 4 V / 65536 = 61.0 µV.
3.5 Signal coupling
The Handyscope TP450 has two different settings for the signal
coupling: AC and DC. In the setting DC, the signal is directly
coupled to the input circuit. All signal components available in the
input signal will arrive at the input circuit and will be measured.
In the setting AC, a capacitor will be placed between the input
connector and the input circuit. This capacitor will block all DC
components of the input signal and let all AC components pass
through. This can be used to remove a large DC component of the
input signal, to be able to measure a small AC component at high
resolution.
12 Chapter 3

When measuring DC signals, make sure to set the signal
coupling of the input to DC.
Introduction 13

14 Chapter 3

Driver installation 4
Before connecting the Handyscope TP450 to the computer,
the drivers need to be installed.
4.1 Introduction
To operate a Handyscope TP450, a driver is required to interface
between the measurement software and the instrument. This driver
takes care of the low level communication between the computer
and the instrument, through USB. When the driver is not installed,
or an old, no longer compatible version of the driver is installed,
the software will not be able to operate the Handyscope TP450
properly or even detect it at all.
The installation of the USB driver is done in a few steps. Firstly,
the driver has to be pre-installed by the driver setup program. This
makes sure that all required files are located where Windows can
find them. When the instrument is plugged in, Windows will detect
new hardware and install the required drivers.
4.2 Where to find the driver setup
The driver setup program and measurement software can be found
in the download section on TiePie engineering’s website and on the
CD-ROM that came with the instrument. It is recommended to
install the latest version of the software and USB driver from the
website. This will guarantee the latest features are included.
4.3 Executing the installation utility
To start the driver installation, execute the downloaded driver
setup program, or the one on the CD-ROM that came with the
instrument. The driver install utility can be used for a first time
Driver installation 15

installation of a driver on a system and also to update an existing
driver.
The screen shots in this description may differ from the ones
displayed on your computer, depending on the Windows version.
Figure 4.1: Driver install: step 1
When drivers were already installed, the install utility will re-
move them before installing the new driver. To remove the old
driver successfully, it is essential that the Handyscope TP450 is
disconnected from the computer prior to starting the driver install
utility.
16 Chapter 4