Cal Test CT2593 User Manual

CT2593

User Manual

Safety Summary

To avoid personal injury and/or product damage, review and comply
with the following safety precautions. These precautions apply to both
operating and maintenance personnel and must be followed during all
phases of operation, service, and repair of this probe.

Only qualied personnel should use this probe. This differential

voltage probe is designed to be used by personnel who are trained,

experienced, or otherwise qualied to recognize hazardous situations

and who are trained in the safety precautions necessary to avoid
possible injury when using such a device.

Do not work alone when working with high voltages.

For your own safety, inspect the probe and accessories for cracks and
frayed or broken leads before each use. If defects are noted, DO NOT
USE the probe.

Hands, shoes, oor and work bench must be dry.

Avoid making measurements under humidity, dampness or other
environmental conditions that might affect safety.

The probe should be kept clean and free of any conductive
contamination.

Do not remove the probe casing. Removal of the probe’s casing may
expose you to electric shock.

Do not use the probe with its case open.

Disconnect the inputs and outputs of the probe before opening the
case.

Use only in ofce-type indoor setting

The probe is designed to be used in ofce-type indoor environments.

Do not operate the probe:

z In the presence of noxious, corrosive, or flammable fumes,

gases, vapors, chemicals, or finely-divided particulates.

z In environments where there is a danger of any liquid being

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spilled on the probe.

z In air temperatures exceeding the specified operating

temperatures.

z In atmospheric pressures outside the specified altitude limits

or where the surrounding gas is not air.

Not for critical applications.

This probe is not authorized for use in contact with the human body or
for use as a component in a life-support device or system.

Hazardous voltages may be present in unexpected locations in circuitry

being tested when a fault condition in the circuit exists.

Do not substitute parts that are not approved by Cal Test Electronics
or modify this probe. Return the probe to Cal Test Electronics for
service and repair to ensure that safety and performance features are
maintained.

WARNING statement calls attention to an operating procedure,

A
practice, or condition, which, if not followed correctly, could result in
injury or death to personnel.

CAUTION statement calls attention to an operating procedure,

A
practice, or condition, which, if not followed correctly, could result in
damage to or destruction of parts or the entire product.

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Compliance Statements

Disposal of Old Electrical & Electronic Equipment

(Applicable in the European Union and other European
countries with separate collection systems). This product
is subject to Directive 2012/19/EU of the European
Parliament and the Council of the European Union on
waste electrical and electronic equipment (WEEE), and in
jurisdictions adopting that Directive, is marked as being
put on the market after August 13, 2005, and should not

be disposed of as unsorted municipal waste. Please utilize

your local WEEE collection facilities in the disposition of

this product and otherwise observe all applicable requirements.

1 Introduction

1.1 Overview

Differential probes allow safe, accurate measurment between to
voltage points where neither point is referenced to ground. The CT2593

family includes two models: The CT2593-1 and CT2593-2 both offering
a 25 MHz bandwidth. Comptable with oscilloscopes from all major

manufacturers, the probes can be battery operated, powered by a
universal adapter (optional), or powered by USB power lead (optional)
if the oscilloscope is so equipped.

Features:

z 25 MHz bandwidth
z Up to ±1.4 kV differential and common mode voltage for the

CT2593-1. Up to ±700 V for CT2593-2.

z Selectable attenuation settings of 20x/200x (CT2593-1) and

10x/100x (CT2593-2)

z Compatible with most oscilloscopes
z Protective rubber boot
z Powered by 4 AA batteries (included)
z Power adapter, CT3723 (optional)
z USB power lead, CT4122 (optional)

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1.2 Initial Inspection

This probe is tested prior to shipment. It is therefore ready for
immediate use upon receipt. An initial physical inspection should be
made to ensure that no damage has been sustained during shipment.
After the inspection, verify the contents of the shipment. The included
accessories for this product are:

z Differential probe
z 2x Hook probes (black & red)
z 4x AA batteries
z Offset adjustment tool
z User manual

2 Product Description

1.1 Front Panel

Output BNC
cable, 95 cm,
with 4 mm
Banana Plug
Ground Lead

Power
On/O
Switch

LED Power
Indicator

Oset
Protective
Rubber Boot

Hook Probes Attenuation

Function Switch

Figure 1 Front Panel Diagram

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Adjustment

Leads,
45 cm

3 Using the Probe

1.1 Power Source

The supplied voltage must greater than 4.4 VDC, and less than 12
VDC, otherwise the probe will not operate properly. When the batteries

are low, the power indicator on the panel will icker.

As an option to the supplied batteries, you may use the CT3723 power

adapter (not included) or the CT4122 USB power lead (not included).

1.2 Replacing the Batteries

Before using the differential probe for the rst time, the batteries

supplied with the device must be inserted in the battery compartment
(unless you are using the power adapter or USB power lead).

WARNING

At the time of inserting or replacing the batteries, the input leads must
not be connected to an item to be tested. Never operate the probe with
the case open.

To insert or replace the batteries, remove the yellow protective rubber
boot by pealing it away from the case and then sliding back the battery
cover. If necessary, the old AA batteries can then be removed and the
new ones inserted into the compartment. Always ensure the batteries
are positioned for proper polarity. After inserting the batteries, close the
case and replace the boot.

1.3 Getting Started

1. Connect the hook probes to the leads.

2. Connect the probe to the oscilloscope with the BNC cable.

The input impedance of the oscilloscope must be 1 MΩ. In

view of the high impedance connection, it is not advisable
to extend the cable. When using an oscilloscope with a 50

Ω input, the actual vertical scale on the oscilloscope will be

doubled (see Table 1). It should also be noted that battery

consumption may increase. As this 50 Ω input is a low

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impedance connection, it is possible to extend the cable

without difculty.

3. Switch the probe “ON.”

4. Switch to the desired attenuation ratio.

5. Use the hook probes to contact the circuit to be tested.

1.4 Vertical Scale on Oscilloscope

The actual vertical scale of the oscilloscope is equal to the attenuation
factor multiplied by the range of vertical scale selected on the

oscilloscope. For example, with the CT2593-1 probe set on attenuation

20x, the oscilloscope on 0.5 V/div, the real vertical scale is 20 x 0.5 =
10 V/div. With the probe on 200x, the real vertical scale is 200 x 0.5
= 100 V/div. These values apply when the oscilloscope is set to the

typical 1 MΩ impedance input. When the oscilloscope is set to 50 Ω

input, the actual vertical scale will be doubled: 20 V/div for the 20x
setting and 200 V/div for the 200x setting. See Table 1.

Vertical Scale on Oscilloscope

(Example using CT2593-1)

Scope Input

Impedance

1 MΩ 20x 20x 0.5 V/div 10 V/div

1 MΩ 200x 200x 0.5 V/div 100 V/div

50 Ω 20x 40x 0.5 V/div 20 V/div

50 Ω 200x 400x 0.5 V/div 200 V/div

Table 1 Oscilloscope Readings

Probe

Attenuation

Setting

Actual

Attenuation

Setting

Vertical Scale

Reading on the

Oscilloscope

Actual Vertical

Scale of the

Oscilloscope

Offset Zero Procedure

The CT2593-1 and CT2593-2 differential probes can be adjusted to
zero the probe’s offset voltage using the offset adjustment tool supplied

with the probe.

Follow this procedure to perform the offset adjustment.

1. Connect the CT2593-1/CT2593-2 probe to channel 1 of

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the scope. Turn on the probe power. You may use the USB
power cable or batteries to power the probe. Set the probe

attenuation ratio to 10x (CT2593-2) or 20x (CT2593-1)

2. Short the + and - probe inputs together with the hook tips.

3. Turn on power to the oscilloscope. Leave both the scope

and the probe on for 30 minutes to stabilize.

4. Press [Default Setup] and [Auto] on the oscilloscope.

5. Press the channel 1 button, then press the Probe softkey
and set the attenuation to 10x.

6. Set the scope to DC coupled mode and the scope offset to 0
volts.

7. Set the oscilloscope to average mode (x16) or high-

resolution mode to reduce oscilloscope noise.

8. Using the offset adjustment tool (included), adjust the probe
offset voltage to 0 volts

4 Cleaning

This probe does not require any particular cleaning. If necessary, clean
the case with a cloth slightly moistened with soapy water

WARNING

Dry the probe thoroughly before attempting to make voltage
measurements.

CAUTION

Do not subject the probe to solvents or solvent fumes as these can
cause deterioration of the probe body and cables.

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Specications

All specications apply to the unit after a temperature stabilization time of 20 minutes over an

ambient temperature range of 25 °C ± 5 °C.

Electrical Specications

CT2593-1 CT2593-2

Bandwidth DC ― 25 MHz

Rise Time (10%-90%) 14 ns

Attenuation ratio 20x/200x 10x/100x

Accuracy ±2%

AC CMRR

Maximum Differential

Input Voltage

(DC + AC peak)

Maximum Common
Mode Input Voltage

(DC + AC peak)

Absolute Maximum
Rated Input Voltage

(each side to ground)

Input Resistance //

Capacitance

Output Voltage Swing ±7 V (driving 1 MΩ oscilloscope input)

Offset (typical) ±5 mV (adjustable)

Noise (typical) 0.7 mVrms

Source Impedance 50 Ω

Power Supply

-80 dB @ 50 Hz

-60 dB @ 20 kHz

±140 V @ 20x

±1.4 kV @ 200x

±140 V @ 20x

±1.4 kV @ 200x

1000 Vrms CAT II

4 MΩ // 5.5 pF (each side to ground)

4 AA batteries (included) or

CT3723 power adapter (optional)

CT4122 USB power lead (optional)

-86 dB @ 50 Hz

-66 dB @ 20 kHz

±70 V @ 10x

±700 V @ 100x

±70 V @ 10x

±700 V @ 100x

Mechanical Characteristics

Weight 400 g (with probe and rubber boot)

Dimensions 170 x 63 x 21 mm

BNC Cable Length 95 cm

Input Leads Length 45 cm each

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Environmental Characteristics

Operating Temp/Humidity -10°C to 40°C / 25% to 85% RH

Storage Temp/Humidity -30°C to 70°C / 25% to 85% RH

Pollution Degree Pollution Degree 2

Altitude

Operating: 3,000 m

Nonoperating; 15,300 m

Safety Specications

IEC 61010-031 CAT II

Specications are subject to change without notice. To ensure the most current version of this

manual, please download the current version from our website: caltestelectronics.com.

5 Voltage Derating Curve

The derating curve of the absolute maximum input voltage in common
mode is show as follows:

CT2593 Maximum Input Voltage Derating Curve

10,000

1,000

Voltage (Vrms)

100

1 103.5 100

Figure 2 Derating Curve

1,000

700

150

Frequency (MHz)

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6 Service & Warranty Information

1.1 Limited One-Year Warranty

Cal Test Electronics warrants this product to be free from defective
material or workmanship for a period of 1 year from the date of original
purchase. Under this warranty, Cal Test Electronics is limited to
repairing the defective device when returned to the factory, shipping
charges prepaid, within the warranty period.

Units returned to Cal Test Electronics that have been subject to abuse,
misuse, damage or accident, or have been connected, installed or
adjusted contrary to the instructions furnished by Cal Test Electronics,

or that have been repaired by unauthorized persons, will not be

covered by this warranty.

Cal Test Electronics reserves the right to discontinue models, change

specications, price, or design of this device at any time without notice

and without incurring any obligation whatsoever.

The purchaser agrees to assume all liabilities for any damages and/or
bodily injury which may result from the use or misuse of this device by
the purchaser, his employees, or agents.

This warranty is in lieu of all other representations or warranties
expressed or implied and no agent or representative of Cal Test

Electronics is authorized to assume any other obligation in connection

with the sale and purchase of this device.

1.2 Service

If you have a need for calibration or repair services, technical or sales
support, please contact us:

22820 Savi Ranch Parkway

Yorba Linda, CA 92887

800-572-1028 or 714-221-9330

caltestelectronics.com

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© 2016 Cal Test Electronics20161026