AEMC instruments MR525 User manual

ENGLISH
User Manual
■
AC/DC CURRENT PROBE
MR525
MR52
6

2Current Probe Models MR525/526
Statement of Compliance
Chauvin Arnoux®, Inc. d.b.a. AEMC®Instruments certifies
that this instrument has been calibrated using standards
and instruments traceable to international standards.
We guarantee that at the time of shipping your instrument
has met its published specifications.
An N.I.S.T. traceable certificate may be requested at the
time of purchase, or obtained by returning the
instrument to our repair and calibration facility, for a
nominal charge.
The recommended calibration interval for this instrument
is 12 months and begins on the date of receipt by the
customer. For recalibration, please use our calibration
services. Refer to our repair and calibration section at
www.aemc.com.
Serial #:
Catalog #: 1200.81 / 1200.83
Model #: MR525/ MR526
Please fill in the appropriate date as indicated:
Date Received:
Date Calibration Due:
Chauvin Arnoux®, Inc.
d.b.a AEMC®Instruments
www.aemc.com

Current Probe Models MR525/526 3
CONTENTS
1 DESCRIPTION................................................................................................. 7
1.1 Interface .................................................................................................................. 8
2 OPERATION .................................................................................................... 9
2.1 Battery Installation.................................................................................................. 9
2.2 External Power (Optional)...................................................................................... 9
2.3 Turning ON the Instrument .................................................................................. 10
2.4 Auto Standby........................................................................................................ 10
2.5 DC Zero Adjustment ............................................................................................ 10
2.6 Measurements ..................................................................................................... 11
2.6.1 Making a Measurement.................................................................... 11
2.6.2 Converting to Current ....................................................................... 11
3 SPECIFICATIONS ......................................................................................... 12
3.1 Reference Conditions .......................................................................................... 12
3.2 Electrical Specifications ....................................................................................... 12
3.2.1 Electrical Specifications, 1mV/A Sensitivity ...................................... 12
3.2.2 Frequency Specifications, 1mV/A Sensitivity.................................... 14
3.2.3 Electrical Specifications, 10mV/A Sensitivity (MR526) ..................... 15
3.2.4 Frequency Specifications, 10mV/A Sensitivity (MR526)................... 17
3.3 Operating Limits ................................................................................................... 18
3.4 Variations in the Range of Use............................................................................ 19
3.5 Power Supply ....................................................................................................... 19
3.6 Environmental Conditions.................................................................................... 20
3.7 Mechanical Specifications ................................................................................... 21
3.7.1 Housing Protection ........................................................................... 21
3.8 International Standards........................................................................................ 21
3.9 Electromagnetic Compatibility ............................................................................. 21
4 MAINTENANCE............................................................................................. 22
4.1 Cleaning................................................................................................................ 22
4.2 Battery Replacement ........................................................................................... 22
REPAIR AND CALIBRATION ........................................................................... 23
TECHNICAL AND SALES ASSISTANCE ......................................................... 23
LIMITED WARRANTY ....................................................................................... 24
Warranty Repairs ....................................................................................................... 24

4Current Probe Models MR525/526
Thank you for purchasing the Current Probe MR525 or MR526. For best results
from your instrument and for your safety, read the following operating instructions
carefully and comply with the precautions for use.
This instrument is compliant with the IEC 61010-2-032 safety standard for voltages
of 300V with respect to earth in measurement category IV, or 600V in category III.
Symbols
WARNING, risk of DANGER! The operator must refer to these instructions
whenever this danger symbol appears.
Application or withdrawal authorized on conductors carrying dangerous
voltages. Type A current sensor as per IEC 61010-2-032.
Equipment is protected by double insulation.
Battery.
USB.
Useful information or tip.
Direction of the current.
The product is declared recyclable following an analysis of the life cycle in
accordance with standard ISO 14040.
The CE marking guarantees conformity with European directives and with
regulations covering EMC.
The trash can with a line through it means that in the European Union, the
product must undergo selective disposal for the recycling of electric and
electronic material, in compliance with Directive WEEE 2002/96/EC.
Definition of Measurement Categories (CAT)
CAT IV Corresponds to measurements taken at the source of low-voltage
installations.
Example: power feeders, counters and protection devices.
CAT III Corresponds to measurements on building installations.
Example: distribution panel, circuit-breakers, machines or fixed industrial devices.
CAT II Corresponds to measurements taken on circuits directly connected to low-
voltageinstallations.
Example: power supply to domestic electrical appliances and portable tools.

Current Probe Models MR525/526 5
PRECAUTIONS FOR USE
These instructions are intended to ensure the safety of users and proper operation
of the instrument. Failure to observe these safety instructions may result in electric
shock, fire, explosion, and destruction of the instrument and/or installations.
The operator and/or the responsible authority must carefully read and clearly
understand the various precautions to be taken in use.
Do not use the instrument on networks on which the voltage or category
exceeds instrument specifications.
Never exceed the protection limits stated in the specifications.
Observe the environmental conditions of use, including relative humidity,
altitude, degree of pollution, and place of use.
Do not use the instrument if it appears to be damaged, incomplete, or not
properly closed.
Before each use, check the condition of the insulation on the leads, housing,
and accessories. Any component on which the insulation is deteriorated (even
partially) must be set aside for repair or scrapping.
When handling the instrument, keep your fingers behind the physical guards.
Use suitable means of protection.
All troubleshooting and metrological checks must be performed by competent
and accredited personnel.

6Current Probe Models MR525/526
RECEIVING YOUR SHIPMENT
Upon receiving your shipment, make sure that the contents are consistent with the
packing list. Notify your distributor of any missing items. If the equipment appears
to be damaged, file a claim immediately with the carrier and notify your distributor
at once, giving a detailed description of any damage. Save the damaged packing
container to substantiate your claim.
Ordering Information
AC/DC Current Probe Model MR525 ........................................... Cat. #1200.81
Includes 9V battery, multi-language safety data sheet and user manual
AC/DC Current Probe Model MR526 ........................................... Cat. #1200.83
Includes 9V battery, multi-language safety data sheet and user manual
Replacement Parts/Accessories:
Cable – 6’ USB type A to Micro type B.............................................Cat. #2138.66
Adapter – US Wall plug to USB........................................................Cat. #2153.78

Current Probe Models MR525/526 7
1 DESCRIPTION
The Models MR525 and MR526 are clamp-on current probes that measure DC
currents up to 1400A, AC currents up to 1000ARMS (1400A peak), and combined
AC+DC currents without opening the circuit in which the currents flow. They
indicate the shape and amplitude of the current measured in the form of a voltage.
These instruments can be used with a multimeter, wattmeter, recorder, and other
instruments. They can be powered by a battery or with 5VDC via the optional
micro‑USB cable.
The MR525 and MR526 include the following features:
range overage indicator
power supply indicator
zero adjustment
Auto Standby feature
one or two ranges, depending on the model (sensitivity 1 and 10mV/A)
micro‑USB connector to connect an external power supply

8Current Probe Models MR525/526
1.1 Interface
Figure 1 (MR525 shown)
Item Function
1 Fixed (non-mobile) jaw
2 Banana plugs (4mm)
3 Arrow indicating current flow direction
4 DC Zero button
5 OL (overload) and ON indicators. ON is green when Auto
Standby is enabled, yellow when it disabled.
6 Slide switch (2-position for MR525, 3-position for MR526)
7 USB port
8 Trigger
9 Hand guard
10 Mobile jaw
1
2
3
4
5
7
8
9
10
6

Current Probe Models MR525/526 9
2 OPERATION
2.1 Battery Installation
Before changing batteries: set the switch to OFF and remove the clamp
from the circuit under measurement.
1. Using a screwdriver, remove the battery compartment cover (1) from the
back of the housing (see Figure 2).
2. Connect the battery to the snap-on connector (2), observing polarity.
3. Place the battery into the battery compartment (3).
4. Replace the battery compartment cover and screw it onto the housing.
Figure 2
2.2 External Power (Optional)
For long‑term measurements, you can connect the clamp to external power via any
micro‑USB adapter that delivers 100mA or more. If external power is disconnected,
the clamp automatically switches to battery operation.
The isolation between the type B micro‑USB connector and the measurement
output is 600V CAT III. This enables you to safely connect the clamp to measuring
instruments with uninsulated inputs. The type B micro‑USB connector must not be
in contact with conductors or uninsulated parts at dangerous voltage.
When operating on external power, the Auto Standby feature is disabled. The color
of the ON indicator shows whether automatic standby is enabled (green) or
disabled (yellow).
1
2
3

10 Current Probe Models MR525/526
2.3 Turning ON the Instrument
Turn on the clamp by pushing the slide switch to the 1mV/A or 10mV/A setting:
1mV/A corresponds to the 1400A range (MR525 and MR526)
10mV/A corresponds to the 150A range (MR526)
The green ON indicator should light up:
If indicator blinks, less than 4 hours of battery life remains
If indicator fails to light, replace the battery (see § 4.2)
2.4 Auto Standby
After 10 minutes of operation without user action (such as pressing the DC Zero
button), the clamp automatically enters Standby mode. In this mode, the ON
indicator goes OFF.
To reactivate the clamp, press DC Zero button or change the switch to any setting
other than OFF.
To disable automatic Standby, press and hold down DC Zero when turning the
instrument ON. The ON indicator blinks to indicate that the request has been
applied; and then glows steady yellow when you release the DC Zero button.
2.5 DC Zero Adjustment
DC Zero must be adjusted before each measurement.
1. Remove the clamp from the circuit under measurement.
2. Turn the clamp ON.
3. Connect the clamp to the measuring instrument. The phase is on the red
lead.
4. Press the DC Zero button.
5. The OL indicator lights for approximately three seconds to indicate that
the zero adjustment is in progress.
6. If the zero has been correctly adjusted, the OL indicator goes OFF.
If it remains ON, the zero cannot be adjusted. In this case, ensure the
clamp is not on a conductor and that its jaws are correctly closed. Then
press DC Zero again.
Alternately, turn the clamp OFF and then back ON. The previous zero
adjustment will remain in effect.

Current Probe Models MR525/526 11
2.6 Measurements
2.6.1 Making a Measurement
After adjusting DC Zero:
1. Press the clamp trigger to open the jaws.
2. Clamp the jaws around the conductor to be measured. Use the centering
marks on the jaws to position the clamp around the conductor. If the
measurement is to be used in a power calculation, ensure the arrow on
the clamp jaws (see Figure 1) points in the direction of the current flow:
source load.
3. Release the trigger, ensuring the jaws are completely and correctly
closed.
4. Observe the measurement displayed on the measuring instrument.
5. If the OL indicator lights, the current is too high to be measured. If you are
using the MR526 and the sliding switch is set to the 10mV/A range,
change the setting to 1mV/A.
Figure 3 (MR526 shown)
2.6.2 Converting to Current
The MR525 and MR526 can both measure current up to 1400A, with 1mV of output
corresponding to 1A. In addition, the MR526 provides a second measurement
range up to 150A, with 10mV corresponding to 1A.
To convert the clamp output to current, divide the voltage reading on the connected
measuring by the V/A coefficient. For example, in the 1400A range a reading of
100mV corresponds to a current of 100A.

12 Current Probe Models MR525/526
3 SPECIFICATIONS
3.1 Reference Conditions
Quantities of Influence Reference Conditions
Temperature 73.4°F ± 9°F (23°C ± 5°C)
Relative humidity 20 to 75 % RH
Position of the conductor Centered on the marks on the jaws
Measurement frequency DC to 65Hz sine wave
External electrical field zero
External DC magnetic field (earth) <40A/m
External AC magnetic field zero
Input impedance ≥ 1MΩ and ≤100pF
The intrinsic uncertainty is the error defined under the reference conditions. It is
expressed as a percentage of the output signal (R) plus an offset in mV:
±(a% R + b)
3.2 Electrical Specifications
3.2.1 Electrical Specifications, 1mV/A Sensitivity
Output impedance: 215
Ω
Specified
Measurement range
0.5 to 100
AAC/DC
100 to 800
AAC/DC
800 to 1000
AAC/DC
1000 to 1400
ADC
Intrinsic uncertainty ≤±(1.5%R +
1 mV) ≤±2.5%R ≤±4%R ≤±5%R
Phase error (45 to 65Hz)
Specified
Measurement range 3 to 200AAC 200 to 1000AAC
Phase shift ≤ -2° ≤ -1.5°

Current Probe Models MR525/526 13
Typical amplitude error curve at 60Hz
Typical amplitude error curve in DC
Typical phase error curve at 60Hz
Error (%)
Current (A)
Error (%)
Current (A)

14 Current Probe Models MR525/526
3.2.2 Frequency Specifications, 1mV/A Sensitivity
Bandwidth -3dB: DC to 30kHz
Frequency 50Hz 400Hz 1kHz 10kHz
Insertion impedance <0.01mΩ0.05mΩ0.14mΩ3.4mΩ
Typical amplitude error versus frequency curve at 100A
Phase shift (°)
Current (A)
Error (%)
Frequency
(Hz)

Current Probe Models MR525/526 15
Typical phase versus frequency error curve at 100A
3.2.3 Electrical Specifications, 10mV/A Sensitivity (MR526)
Output impedance: 215
Ω
Specified
Measurement range 0.5 to 40AAC/DC 40 to 100AAC/DC 100 to 150ADC
Intrinsic uncertainty ≤±(3%R + 5mV) ≤±1.5%R ≤±1.5%R
Phase error (45 to 65Hz)
Specified Measurement range 10 to 100AAC
Phase shift ≤
‑ -2°
Phase shift (°)
Frequency
(Hz)

16 Current Probe Models MR525/526
Typical amplitude error vs current curve at 60Hz
Typical amplitude error vs current curve in DC
Error (%)
Current (A)
Error (%)
Current (A)

Current Probe Models MR525/526 17
Typical phase vs current error curve at 60Hz
3.2.4 Frequency Specifications, 10mV/A Sensitivity (MR526)
Bandwidth -3dB: DC to 30kHz
Frequency 50Hz 400Hz 1kHz 10kHz
Insertion impedance <0.01mΩ0.05mΩ0.14mΩ3.4mΩ
Typical amplitude error versus frequency curve at 100A
Typical phase versus frequency error curve at 100A
Phase shift (°)
Current (A)
Error (%)
Frequency
(Hz)

18 Current Probe Models MR525/526
3.3 Operating Limits
In DC: 3000A permanent
In AC: 1000A permanent up to 1kHz
from 1kHz, IMAX = 1000/f (kHz)
Conductor temperature: ≤ 194°F (90°C), 230°F (110°C) peak
Temperature of the jaws: ≤ 176°F (80°C)
Curve of derating versus frequency
Phase shift (°)
Frequency
(Hz)
Current (A)
Frequency
(kHz)

Current Probe Models MR525/526 19
3.4 Variations in the Range of Use
Quantity of influence Range of influence
Error in % of reading
Typical Maximum
Temperature 14 to 131°F
(‑10 to + 55°C) 0.3%
Relative humidity 10 to 85% RH 0.5%
Frequency
10 to 400Hz
400Hz to 7kHz
7 to 30kHz
1%
3.5%
see curves
Position of the conductor
0.79” (20mm) in diameter 0.5%
Adjacent conductor
carrying a 50Hz AC current
Conductor 0.91” (23mm)
from the clamp 10mA/A
External 400A/m field
at 50Hz Cable centered 1.3A
Common mode rejection 600V between the jacket
and the secondary 65dB A/V at 50Hz
Remanence
100ADC: 2.8A
200ADC: 3.5A
400ADC: 5A
800ADC: 5.3A
1200ADC: 5.7A
1400ADC: 5.8A
3.5 Power Supply
The instrument is powered by a 9V battery (type 6LR61, 6LF22, or NEDA 1604).
The average battery life is 50 hours with an alkaline battery.
The instrument can also be powered by an external supply (5VDC, 100mA) via the
type B micro‑USB connector.

20 Current Probe Models MR525/526
3.6 Environmental Conditions
The instrument must be used in the following environmental conditions.
1 = Range of reference
2 = Operating range
3 = Storage range
Indoor use
Degree of pollution: 2
Altitude: < 6500’ (2000m)
Transport altitude: ≤ 40,000’ (12,000m)
%RH
°C