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Warning statements identify conditions or practices
TA057
25 MHz ±1400 V Differential Probe
User’s Manual
This probe complies with IEC-1010.1, IEC-1010.2-031 CAT III,
Pollution Degree 2.
1. Safety terms and symbols
1 28.8.2008.
James House
Colmworth Business Park
St. Neots
PE19 8YP
United Kingdom
www.picotech.com
Terms appearing in this manual:
WARNING
CAUTION Caution statements identify conditions
that could result in injury or death.
that could result in damage
property.
Symbols appearing on the product:
Danger
High Voltage
Protective
(Earth) Terminal
Refer to Manual
Attention
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output lead is grounded. You
may do this either by connecting the BNC shell to a
ary grounding terminal to a
point. Read the next paragraph for
2. General safety summary
Please review the following safety precautions to avoid injury and prevent damage
to this probe or any products that are connected to it.
Observe maximum working voltage
To avoid any injury, do not use the probe above 1000 V RMS CAT III between each
input lead and earth or between the two input leads. This voltage rating applies to
both the 1/20 and 1/200 settings.
Must be grounded
This probe is grounded with the shell of the BNC connector and an auxiliary
grounding terminal.
WARNING Before making connections to the input leads of th
You must verify that the probe is securely grounded before connecting the probe
input leads. Some types of measuring instrument, such as a USB oscilloscope
connected to a laptop, are unlikely to be grounded even if the laptop is powered
from the mains. Bench-top oscilloscopes are usually grounded, but in some cases
may have been isolated from ground. A USB oscilloscope connected to a desktop
computer is usually grounded. In any case, do not assume that the measurement
instrument is grounded. Always verify the ground connection for yourself
before connecting the probe input leads.
Use fused test prods if necessary
If this probe is intended to use for measurements in circuits of INSTALLATION
CATEGORY III, it should incorporate with fused test prods.
Do not operate without covers
To avoid electric shock or fire hazard, do not operate this probe with the covers
removed.
Do not operate in wet or damp conditions
To avoid electric shock, do not operate this probe in wet or damp conditions.
Do not operate in explosive atmosphere
To avoid injury or fire hazard, do not operate this probe in an explosive atmosphere.
probe, ensure that its
grounded measurement instrument
connecting the auxili
reliable ground
further advice.
8. Derating curve
The derating curve for absolute maximum input voltage in common mode is as
follows:
10000
1000
1000
Voltage (V RMS)
100
1.E+06 1.E+07 1.E+08
1000
700
150
Frequency (Hz)
9. Test procedure
a. Connect the BNC output connector to the vertical input of a general-purpose
oscilloscope.
b. To install four AA cells or connect an appropriate mains adaptor or power lead
to the correct line voltage.
c. Set the oscilloscope input coupling to DC and 1 V/div. Center the trace on the
display.
d. Connect the inputs of the probe to power lines.
e. Set the range of the probe to 1/100 or 1/200.
f. A 50 Hz / 60 Hz sine-wave of 1 V amplitude will be displayed on the screen of
the oscilloscope. This means the probe is working properly.
10. Cleaning
Use a soft cloth to clean the probe, taking care not to cause damage.
a. Do not immerse the probe.
b. Do not use abrasive cleaners.
c. Do not use chemicals contains benzene or similar solvents.
Avoid exposed circuitry
To avoid injury, remove jewelry such as rings, watches and other metallic objects.
Do not touch exposed connections and components when power is present.
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accessories designed for use with this differential
under test. It is not intended for electrically
insulating the circuit under test and the measuring
7. Specifications
Bandwidth DC to 25 MHz (-3 dB)
Attenuation ratio 1:20/200
Accuracy ±2%
Rise time 14 ns
Input Impedance 4 MΩ// 5.5 pF each side to ground
Input Voltage
Differential Range*
Common Mode Range*
Absolute Max. Voltage*
(Differential or common mode)
Output
Max. amplitude ±7 V into 50 kΩ load
Offset (typical) < ±5 mV
Noise (typical) 0.7 mV rms
Source impedance (typical) 1 Ω @ 1 kHz, 8 Ω @ 1 MHz
CMRR (typical) -80 dB @ 50 Hz; -60 dB @ 20 kHz
Ambient operating temperature -10 to +40 °C
Ambient storage temperature -30 to +70 °C
Ambient operating humidity 25 to 85% RH
Ambient storage humidity 25 to 85% RH
Power Requirements
Standard
Options Power leads
Length of input leads 45 cm
Length of BNC lead 95 cm
Weight 400 g (including probe and PVC jacket)
Dimension (LxWxH) 170 mm x 63 mm x 21 mm
* Voltage limit is the lesser of the DC+Peak AC and RMS values.
**
a. The supplied voltage must be less than 12 V and greater than 4.4 V, otherwise
the probe could be damaged or might not operate properly.
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 change colour and then switch off.
±140 V (DC+Peak AC) or 140 V RMS @ 1/20
±1400 V (DC+Peak AC) or 1000 V RMS @ 1/200
±1400 V (DC+Peak AC) or 1000V RMS
@ 1/20 and 1/200
±1400 V (DC+Peak AC) or 1000 V RMS CAT III
@ 1/20 and 1/200
4xAA cells or 6 V DC / 60 mA mains adaptor**
or regulated 9 V DC / 40 mA mains adaptor**
Use proper power source
To ensure proper functioning of this probe, use four AA cells or a 6 V DC / 60 mA
mains adaptor or regulated 9 V DC / 40 mA mains adaptor or power lead.
Do not operate the probe if it is damaged
If you suspect there is damage to this probe, have it inspected by qualified service
personnel.
3. Description
By enabling conventional oscilloscopes to display and measure in-circuit waveforms
that are referenced to high common-mode voltages, this differential probe extends
the measurement capability of oscilloscopes to electronic power converters,
inverters, motor speed controls, switch mode power supplies, and many other
applications.
4. Installation
a. Simply plug in the BNC output connector to the vertical input of a
general-purpose oscilloscope or other measurement instrument, and connect
the auxiliary grounding terminal to a proper ground. The measurement
instrument must have a ground reference.
b. Install four AA cells or connect an appropriate power source to the probe.
c. Select the proper attenuation ratio. When measuring signals below 140 V,
switch the attenuation ratio to 1/20 in order to get higher resolution and less
noise. Otherwise, set the attenuation to 1/200.
WARNING To protect against electric shock,
d. Using the appropriate probe accessories, connect the input to the circuits under
measurement.
CAUTION This probe is designed for carrying out differential
probe.
measurements between two points on
instrument.
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5. Appearance
The differential probe looks like this:
a. Output Cable. The BNC output connector and an auxiliary grounding terminal
are connected to the oscilloscope.
b. Input Leads. The input leads of the differential probe connect to sprung
hooks that come with the probe.
c. Sprung Hooks. The sprung hooks are connected safely to test points in
circuits under measurement.
6. Power leads
Two types of power leads are available for use with this instrument:
a. Lemo
b. Probus
®
Lead: For oscilloscopes with Lemo® power connectors.
®
Lead: For oscilloscopes with Probus® power connectors.
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