Differential probes
User’s Guide

TA041

25 MHz ±700 V x10/x100

TA042

100 MHz ±1400 V x100/x1000

TA043

100 MHz ±700 V x10/x100

TA044

70 MHz ±7000 V x100/x1000

TA057

25 MHz ±1400 V x20/x200

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Differential Probes User’s Guide

Contents
1.

Description

1

2.

Safety13.

Installation

5

4.

Appearance

65.

TA531 USB to DC power lead

7

6.

Overrange indicator

7

7.

Specifications

8

8.

Derating curves

99.

Test procedure

10

10.

Calibration

10

11.

Zero probe offset

11

12.

Cleaning

11

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Differential Probes User’s Guide
1. Description
TA041, TA042, TA043, and TA057 CAT III probes
These CAT III differential probes enable conventional oscilloscopes to display and measure
in-circuit waveforms that are high-voltage or are referenced to high common-mode voltage. Thisextends the measurement capability of oscilloscopes to include electrical power conversion,
inversion, motor speed control, switch-mode power supply and many other applications.
TA044 probe
The TA044 is an active differential probe suitable for high common-mode voltage measurement
applications up to ±7000 V (DC + peak AC). This differential probe extends the functionality ofstandard single-ended input oscilloscopes to allow a safe and accurate method of making highvoltage differential measurements. Applications include making safe measurements in power
circuit applications and acquisition of low-speed balanced differential signals found in serial
communications buses.

2. Safety
To prevent possible electrical shock, fire, personal injury, or damage to the product, carefully
read this safety information before attempting to install or use the product. In addition, follow all
generally accepted safety practices and procedures for working with and near electricity.
These probes have been designed and tested in accordance with the Harmonized Standard EN
61010-031:2015, and left the factory in a safe condition.
The following safety descriptions are found throughout this guide:
A WARNING identifies conditions or practices that could result in injury or death.
A CAUTION identifies conditions or practices that could result in damage to the product orequipment to which it is connected.

Symbols
These safety and electrical symbols may appear on the product or in this guide.
SymbolDescription
Earth (ground) terminal

Equipment protected through double or reinforced insulation

Possibility of electric shock
Caution. Appearance on the product indicates a need to read these safety
and operation instructions.
IEC 61010 overvoltage category

Do not dispose of this product as unsorted municipal waste

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Differential Probes User’s Guide
WARNINGTo prevent injury or death use the product only as instructed. Protection
provided by the product may be impaired if used in a manner not specified by the
manufacturer.

Maximum input ranges
Observe all terminal ratings and warnings marked on the product.
WARNINGTo prevent electric shock, do not use the probe with voltages above the absolute
maximum values specified in the following table.
Model

Probe
bandwidth

Differential
range(s)Absolute max. voltage

SafetyCAT rating

TA041

25 MHz±70/700 V±1000 V pk max

1000 V CAT III

TA042

100 MHz±140/1400 V±1400 V pk max

1000 V CAT III

TA043

100 MHz±70/700 V±1000 V pk max

1000 V CAT III

TA057

25 MHz±140/1400 V±1400 V pk max

1000 V CAT III

TA044

70 MHz±700/7000 V

5000 Vrms or ±7000 V(DC+Peak AC) in differential mode

non CAT rated

WARNING
Signals exceeding the voltage limits in the table below are defined as “hazardous
live” by EN 61010. To prevent electric shock, take all necessary precautions whenworking on equipment where hazardous live voltages may be present.

Signal voltage limits of the Low Voltage Directive (LVD)±60 V DC

30 V AC RMS±42.4 V pk max.

WARNINGTo prevent injury or death, the TA044 differential probe must not be directly
connected to the mains (line power). To measure mains voltages, use a CAT III
differential isolating probe specifically rated for mains use, such as the TA041.
CAUTION
Operation outside of the safe voltage range is likely to cause permanent damage
to the product and other connected equipment.

2

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Differential Probes User’s Guide
Grounding
WARNING
The probe’s ground connection through the BNC cable is for measurement
purposes only. The probe does not have a protective safety ground.
The probe can be grounded by connecting the BNC shell to a groundedmeasurement instrument, or by connecting the auxiliary grounding terminal to areliable ground point. Some measurement setups, such as a USB oscilloscope
connected to a laptop, are unlikely to be grounded even when the laptop is mains
powered.

External connections
WARNINGTo prevent electric shock, do not touch exposed connections and components
when power is present.
CAUTION
Take care to avoid mechanical stress or tight bend radii for all connected leads.
Mishandling will cause deformation of sidewalls, and will degrade performance andmeasurement accuracy.

Environment
WARNINGTo prevent injury or death, do not use in wet or damp conditions, or near explosivegas or vapor.
WARNINGTo avoid injury or death, always remove jewellery such as rings, watches and othermetallic objects.
CAUTIONTo prevent damage, always use and store your probe in appropriate environments
as shown below:

Temperature

DO241-3–10 to 40 °C (operating)–30 to 70 °C (storage)

Humidity

25 to 85 %RH (operating and storage)

Altitude2000 mPollution

Degree 2

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Differential Probes User’s Guide
Care of the product
The product contains no user-serviceable parts. Repair, servicing and calibration require
specialized test equipment and must only be performed by Pico Technology or an approved
service provider. There may be a charge for these services unless covered by the Pico two year
warranty.
WARNINGTo prevent injury or death, do not use the product if it appears to be damaged in any
way, and stop use immediately if you are concerned by any abnormal operations.
WARNINGTo prevent injury or death, do not operate this probe with the covers removed.
WARNINGTo prevent injury or death, do not tamper with or disassemble the probe or its
accessories. Internal damage will affect performance.
WARNINGTo prevent injury or death when cleaning the product, use a soft cloth and asolution of mild soap or detergent in water. To prevent electric shock, do not allow
liquids to enter the casing, as this will compromise the electronics or insulation
inside. Always ensure that the probe is dry before connecting it to the oscilloscope,
power supply, or device under test.

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Differential Probes User’s Guide
3. Installation
Follow these instructions to install and start using your differential probe.
1.

Simply plug in the BNC output connector to the vertical input of a general-purpose
oscilloscope or other measurement instrument.

2.

Connect to probe to an appropriate power source; internal batteries or TA531 USB to DC
power lead.

3.

Turn the probe on.

4.

Set the attenuation ratio according to the table below.

5.

Using the appropriate probe accessories, connect the input to the circuit under test.

Probe
TA041
TA042
TA043
TA044
TA057

Signal voltage

Attenuation ratio< 70 V

1:10≥ 70 V

1:100< 140 V

1:100

≥ 140 V

1:1000< 70 V

1:10≥ 70 V

1:100< 700 V

1:100

≥ 700 V

1:1000< 140 V

1:20

≥ 140 V

1:200

WARNINGTo protect against electric shock, use only the accessories designed for use withthis differential probe.
WARNINGTo avoid injury or death, you must observe all safety precautions appropriate to thecircuit under test.

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Differential Probes User’s Guide
4. Appearance
TA041, TA042, TA043, TA044, and TA057 probes
a

b

c

d

e

f

g
a.

h

Sprung hooks
The sprung hooks allow a safe connection to test points in the circuits under test.

b.

Input leads
The input leads of the differential probe connect to the sprung hooks that are supplied withthe probe.

c.

Probe bodyd.

Attenuation ratio switch (some probes may have controls in a different configuration)e.

Overrange indicatorf.

Output lead
The BNC output connector and an auxiliary grounding terminal are connected to theoscilloscope.

g.

DC power socket, for use with TA531 USB to DC power lead.
See Section 5 for more information on connecting power leads.

h.

6Power switch

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Differential Probes User’s Guide
5. TA531 USB to DC power lead

TA531 USB to DC power lead

To USB power supply

DIFFERENTIAL PROBE

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1/10

1/100
I

0

POWER

Oscilloscope front panel

6. Overrange indicator
The overrange indicator lights up red if the voltage of the input signal exceeds the linear operating
range of the probe. When this happens, the signal on the probe output may not accurately
represent the signal on the probe input.
The overvoltage indicator is found on the front panel of the probe.

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8

TA041

Source impedance (typical)

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202 mm x 83 mm x 38 mm

500 g

90 cm

30 cm

6 V DC 200 mA or
regulated 9 V DC 120 mA

80 dB at 60 Hz. 50 dB at 1 MHz.

50 Ω

0.9 mV RMS< ±5 mV±1.4 V into 1 MΩ load

±1400 V (DC + AC peak) or
1000 V RMS CAT III (1:100 and 1:1000)

TA043

202 mm x 83 mm x 38 mm

500 g

90 cm

30 cm

TA531 Power lead

6 V DC 200 mA or
regulated 9 V DC 120 mA

4 x AA cells

25 to 85 %RH (operating and storage)–10 to 40 °C (operating)–30 to 70 °C (storage)

85 dB at 50 Hz. 55 dB at 1 MHz.

50 Ω

0.9 mV RMS< ±5 mV±7 V into 1 MΩ load

±1000V (DC + AC peak) or 1000V RMS CAT
III (1:10 and 1:100)±700 V (DC + peak AC)
or 700 V RMS (1:10 and 1:100)±700 V (DC + peak AC)
or 500 V RMS (1:100)±70 V (DC + peak AC)
or 70 V RMS (1:10)

4 MΩ ∥ 7 pF each side to ground

3.5 ns±2%

1:10 or 1:100 switchable

DC to 100 MHz (–3 dB)

TA044

202 mm x 83 mm x 38 mm

500 g

90 cm

60 cm

6 V DC 200 mA or
regulated 9 V DC 120 mA

80dB at 50Hz, 60dB at 20kHz

50 Ω

0.9 mV RMS< ±5 mV±7 V into 1 MΩ load

±7000 V (DC + AC peak) or
5000 V RMS (1:100 and 1:1000)±7000 V (DC + peak AC)
or 2500 V RMS (1:100 and 1:1000)±7000 V (DC + AC peak) or2500 V RMS (1:100 and 1:1000)±7000 V (DC + peak AC)
or 5000 V RMS (1:1000)±700 V (DC + peak AC)
or 700 V RMS (1:100)

10 MΩ ∥ 10 pF each side to ground

5 ns

±2%

1:100 or 1:1000 switchable

DC to 70 MHz (–3 dB)

TA057

170 mm x 63 mm x 21 mm

400 g (inc. probe and PVC jacket)

95 cm

45 cm

6 V DC 60 mA or
regulated 9 V DC 40 mA

86 dB at 50 Hz. 60 dB at 20 kHz.

50 Ω

0.7 mV RMS< ±5 mV±7 V into 1 MΩ load

±1400 V (DC + AC peak)or 1000 V RMS CAT III±1400 V (DC + peak AC)
or 1000 V RMS (1:20 and 1:200)±1400 V (DC + peak AC)
or 1000 V RMS (1:200)±140 V (DC + peak AC)
or 140 V RMS (1:20)

4 MΩ ∥ 5.5 pF each side to ground

14 ns

±2%

1:20 or 1:200 switchable

DC to 25 MHz (–3 dB)*       Voltage limit is the lesser of the DC + AC peak and RMS values.
** a. The supplied voltage must be between 3.3 V and 16 V (TA057), or 4.4 V and 12 V (all other models). Voltages outside of this range may damage the probe or affect performance.
     b. Polarity is “+” inside and “–” outside.  If the polarity is wrong, a built-in circuit protects the probe so that no danger or damage will occur.
     c. When the voltage of the cells becomes too low, the power indicator on the panel will flash red and green, then switch off (TA057 and TA041) or flash red and switch off (all other models).

170 mm x 63 mm x 21 mm

Specification table notes:

Dimensions (L x W x H)

400 g (inc. probes and PVC jacket)

95 cm

BNC cable

Weight45 cm

6 V DC 60 mA or
regulated 9 V DC 40 mA

Input cable

Optional

Mains adaptor(s) **Battery **Power requirements

Humidity

Temperature

86 dB at 50 Hz. 66 dB at 20 Hz.

50 Ω

0.7 mV RMS

Noise (typical)±7 V into 1 MΩ load

±1400 V (DC + AC peak) or
1000 V RMS CAT III (1:10 and 1:100)±1400 V (DC + peak AC)
or 1000 V RMS (1:100 and 1:1000)±700 V (DC + peak AC)
or 700 V RMS (1:10 and 1:100)±140 V (DC + peak AC)
or 140 V RMS (1:100)

4 MΩ ∥ 7 pF each side to ground

3.5 ns±2%

1:100 or 1:1000 switchable±1400 V (DC + peak AC)
or 1000 V RMS (1:1000)< ±5 mV

CMRR (typical)

TA042
DC to 100 MHz (–3 dB)±700 V (DC + peak AC)
or 700 V RMS (1:100)±70 V (DC + peak AC)
or 70 V RMS (1:10)

Offset (typical)

Swing

OutputAbsolute max. voltage *(Differential mode)

Absolute max. voltage *(Common mode)

Common mode range *Differential range *Input voltages

4 MΩ ∥ 5.5 pF each side to ground

14 ns

Rise time

Input impedance±2%

1:10 or 1:100 switchable

DC to 25 MHz (–3 dB)

DC accuracy

Attenuation ratio

Bandwidth

7. Specifications

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Differential Probes User’s Guide
8. Derating curves
The derating curves for absolute maximum input voltage of each probe model are shown below:

TA041 and TA057

Voltage (V RMS)

10000

1000

1000

1000

700

150
100

1M

10 M

100 M

Frequency (Hz)TA042

Voltage (V RMS)

10000
1000

1000
1000

100

20
10

100 k

1M

10 M

100 M

Frequency (Hz)TA043

Voltage (V RMS)

10000
1000

1000

1000

100
20
10
100 k

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1M

Frequency (Hz)10 M

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100 M

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Differential Probes User’s Guide
TA044

Voltage (V RMS)

10000
2500

2500

1000
200
100
20
10
100 k

1M

10 M

100 M

Frequency (Hz)9. Test procedure1.

Connect the BNC output connector to the vertical input of a general-purpose oscilloscope.

2.

Connect the probe to an appropriate power source, such as the mains adaptor or four AA
cells.

3.

Turn on the probe using the power switch.

4.

Set the oscilloscope input to DC coupling and 1 V/div. Center the trace on the display.

5.

Connect the sprung hooks of the probe to the circuit under test.

6.

A 50 Hz or 60 Hz sine wave of proper amplitude will be displayed on the screen of theoscilloscope. This demonstrates that the probe is working properly.

10.

Calibration

There are three main sources of uncertainty when calibrating a Pico differential probe in addition
to any uncertainty in the test setup. These are:1.

The stated DC accuracy of the probe under test (see specifications table).

2.

Any DC offset or noise in the probe output. The values in this manual are typical, so to findthe DC  offset for a given unit a reading must be taken with the inputs to the probe shorted
together.

3.

The AC performance of the probe. This is specified as being within 3 dB over the entire
frequency range of the probe. Any absolute voltage accuracy testing must be done under DC
conditions.

One other possible cause of noise is the probe’s power source. It is recommended that, where
possible, probes are calibrated using a battery supply rather than a mains supply unit.
The adjustment procedure is available from Pico Technology on request.

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Differential Probes User’s Guide
11.

Zero probe offset

The probes can be adjusted for zeroing out the probe’s offset voltage using a trimmer tool
supplied with the probe. Follow this procedure to perform the offset-zero calibration:
1. After turning on the power to the oscilloscope and probe, leave them on for >30 minutes tostabilize. You may use the USB power cord or batteries to power the probe.
2. Connect the probe to channel A of your oscilloscope.
3. Short the + and – probe inputs together with the hook tips.
4. Select Auto range in the oscilloscope software.
5. Then set units to Volt and select the lowest attenuation.
6. Set the ocsilloscope to DC coupled mode.
7. Position the ground of the waveform to the centre of the screen and set the vertical scale to
10 mV/div or 20 mV/div.
8. Set the oscilloscope to Averaging mode (x8 or higher) or High resolution mode to reduce
scope noise.
9. Using the trimmer tool supplied with the probe, adjust the probe offset voltage to 0 V.

12.

Cleaning

Only use a soft, damp cloth to clean the probe.
WARNINGTo prevent injury or death, always ensure the probe is thoroughly dry after
cleaning.

CAUTIONTo prevent damage to the probe and other connected equipment, do not
immerse the probe in any liquids.

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