FLIR CM94 User manual

USER MANUAL
True RMS AC/DC
2000A Utility
Clamp Meter
Model CM94

USER MANUAL
True RMS AC/DC 2000A
Utility Clamp Meter
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Table of contents
1 Advisories ..........................................................................1
1.1 Copyright..................................................................1
1.2 Quality Assurance ...................................................... 1
1.3 Documentation ..........................................................1
1.4 Disposal of Electronic Waste.........................................1
2 Introduction........................................................................2
3 Safety ................................................................................3
3.1 General Safety Information ........................................... 3
3.2 Safety Terms Used In This Manual ................................. 3
3.3 Warning and Caution Statements ................................... 3
3.4 International Electrical Symbols ..................................... 5
3.5 CENELEC Directives................................................... 5
4 Descriptions .......................................................................6
4.1 Product Description.....................................................6
4.2 Control Button Descriptions ..........................................7
4.3 Rotary Switch Positions................................................ 7
4.4 Display Description ..................................................... 8
5 Meter Operation ..................................................................9
5.1 Powering the Meter ..................................................... 9
5.2 Auto Power OFF (APO)................................................ 9
5.3 Automatic and Manual Ranges ...................................... 9
5.4 Out-of-Range Alert.................................................... 10
5.5 Display Hold Function................................................ 10
5.6 Display Backlight ..................................................... 10
5.7 AC and DC Voltage Measurements............................... 10
5.8 LoZ Voltage Measurements ........................................ 12
5.9 Low Pass Filter (VFD) AC Voltage Measurements ............ 12
5.10 Current Clamp Measurements..................................... 13
5.11 Resistance Measurements ......................................... 14
5.12 Continuity Measurements ........................................... 15
5.13 Diode Measurements ................................................ 16
5.14 Capacitance Measurements ....................................... 18
5.15 Type-K Thermocouple Measurements ........................... 19
5.16 Non-Contact AC Voltage Detector ................................ 20
6 Maintenance..................................................................... 22
6.1 Cleaning................................................................. 22
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Table of contents
6.2 Battery Replacement................................................. 22
6.3 Meter Storage.......................................................... 22
7 Specifications................................................................... 23
7.1 General Specifications............................................... 23
7.2 DC Voltage Specifications .......................................... 24
7.3 LoZ (DC Voltage) Specifications................................... 24
7.4 AC Voltage Specifications........................................... 24
7.5 LoZ (AC Voltage) Specifications................................... 25
7.6 VFD (low pass filter) AC Voltage Specifications ............... 25
7.7 PEAK HOLD Capture Mode Specifications..................... 25
7.8 Resistance Specifications........................................... 25
7.9 Continuity Specifications ............................................ 25
7.10 Capacitance Specifications......................................... 26
7.11 Diode Specifications ................................................. 26
7.12 DC Current Specifications (Clamp) ............................... 26
7.13 AC Current Specifications (Clamp) ............................... 26
7.14 Hz Line Level Frequency Specifications......................... 27
7.15 Temperature Specifications......................................... 27
7.16 Non-Contact AC Voltage Detector (NCV) ....................... 28
7.17 Input Specifications................................................... 28
7.18 Safety Specifications ................................................. 28
8 Three-Year Warranty .......................................................... 29
9 Customer Support............................................................. 30
9.1 Corporate Headquarters ............................................ 30
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Advisories
1
1.1 Copyright
©2019, FLIR Systems, Inc. All rights reserved worldwide. No parts of the
software including source code may be reproduced, transmitted, transcribed
or translated into any language or computer language in any form or by any
means, electronic, magnetic, optical, manual or otherwise, without the prior
written permission of FLIR Systems.
The documentation must not, in whole or part, be copied, photocopied, repro-
duced, translated or transmitted to any electronic medium or machine-read-
able form without prior consent, in writing, from FLIR Systems. Names and
marks appearing on the products herein are either registered trademarks or
trademarks of FLIR Systems and/or its subsidiaries. All other trademarks,
trade names or company names referenced herein are used for identification
only and are the property of their respective owners.
1.2 Quality Assurance
The Quality Management System under which these products are developed
and manufactured has been certified in accordance with the ISO 9001
standard.
FLIR Systems is committed to a policy of continuous development; therefore,
we reserve the right to make changes and improvements on any of the prod-
ucts without prior notice.
1.3 Documentation
To access the latest manuals and notifications, go to the Download tab at:
https://support.flir.com. It only takes a few minutes to register online. In the
download area you will also find the latest releases of manuals for our other
products, as well as manuals for our historical and obsolete products.
1.4 Disposal of Electronic Waste
As with most electronic products, this equipment must be disposed
of in an environmentally friendly way, and in accordance with existing
regulations for electronic waste. Please contact your FLIR Systems
representative for more details.
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Introduction
2
The CM94 is a high accuracy, rugged measurement instrument intended for
the electrical utility and industrial maintenance professional for inspecting and
troubleshooting high voltage/current electrical infrastructure systems and
equipment. The low input impedance mode (LoZ) helps determine whether a
measured voltage is ‘real’ or induced by load carrying cables running adjacent
and parallel to the measurement target (ghost voltage).
Visit https://www.support.flir.com/prodreg to register your CM94 and to read
the three-year warranty text.
Features
• Primary 6000 count and secondary 1999 count dual backlit displays
• Dual display of ACA + Hz and ACV + Hz
• Rated CAT IV 1000V / 2000A
• True RMS sensing
•VFD-V and VFD-Hz for use with variable speed drives
• Non-contact voltage detection (NCV)
• PEAK mode captures Peak Min and Peak Max current/voltage in 5 millisec-
ond window
• Data Hold and Relative/Zero modes
• Auto Power OFF (APO) in 34 minutes
•LoZ mode to help detect ‘ghost’ voltages
• Type-K thermocouple temperature measurements
• Large jaws accommodate 2.2 in. (55 mm) cables
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Safety
3
3.1 General Safety Information
This user manual contains information and warnings that must be followed for
operating the instrument safely and maintaining the instrument in a safe oper-
ating condition. If the instrument is used in a manner not specified by the man-
ufacturer, the protection provided by the instrument may be impaired.
The meter protection rating, against the users, is double insulation per UL/
IEC/EN61010-1 Ed. 3.0, IEC/EN61010-2-033 Ed. 1.0, CAN/CSA C22.2 No.
61010-1 Ed. 3.0, IEC/EN61010-2-032 Ed. 3.0 & IEC/EN61010-031 Ed. 1.1:
Measurement Category IV 1000V AC & DC.
Per IEC61010–1 OVERVOLTAGE CATEGORY
OVERVOLTAGE CATEGORY II (CAT II) is for equipment intended to be sup-
plied from the building wiring. It applies both to plug-connected equipment
and to PERMANENTLY CONNECTED EQUIPMENT.
OVERVOLTAGE CATEGORY III (CAT III) is for equipment intended to form
part of a building wiring installation. Such equipment includes socket outlets,
fuse panels, and some MAINS installation control equipment.
OVERVOLTAGE CATEGORY IV (CAT IV) is for equipment installed at or near
the origin of the electrical supply to a building, between the building entrance
and the main distribution board. Such equipment may include electricity tariff
meters and primary over-current protection devices.
3.2 Safety Terms Used In This Manual
WARNING: Identifies conditions and actions that could result in serious injury
or even death to the user.
CAUTION: Identifies conditions and actions that could cause damage or mal-
function in the instrument.
3.3 Warning and Caution Statements
WARNING
To reduce the risk of fire or electric shock, do not expose this product to rain or moisture.
The meter is intended only for indoor use.
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Safety
3
WARNING
To avoid electrical shock hazard, observe the proper safety precautions when working with
voltages above 60 VDC or 30 VAC rms. These voltage levels pose a potential shock haz-
ard to the user. Before and after hazardous voltage measurements, test the voltage func-
tion on a known source such as line voltage to determine proper meter functioning.
WARNING
Keep hands/fingers behind the hand/finger barriers (of the meter and the test leads) during
measurement. Inspect test leads, connectors, and probes for damaged insulation or ex-
posed metal before using the instrument. If any defects are found, replace them immedi-
ately. Use only the test leads provided with the equipment (or UL Listed probe assemblies
rated CAT IV 1000V or better).
WARNING
The accompanied test probe assembly meets UL/IEC/EN61010-031 Ed. 1.1 to the same
meter ratings or better. IEC 61010-031 requires exposed conductive test probe tips to be
≤ 4mm for CAT III & CAT IV ratings. Refer to the category markings on your probe assem-
blies as well as on the add-on accessories (detachable Caps or Alligator Clips, etc.), if any,
for applicable rating changes.
WARNING
This Clamp meter is designed for clamping around or removing from non-insulated, haz-
ardous live conductors. Nonetheless, individual protective equipment must be used when
hazardous live parts in the installation, where the measurement is to be made, could be
accessible.
WARNING
Remove test leads from the meter before taking clamp measurements.
CAUTION
Disconnect the test leads from the test points before changing meter functions.
CAUTION
Do not use the device for a procedure that it is not intended for. This can cause damage to
the protection built into the instrument.
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Safety
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3.4 International Electrical Symbols
Caution! Refer to the explanation in the user manual.
Caution! Risk of electrical shock.
Earth ground.
Double/reinforced insulation.
Fuse.
AC (alternating current).
DC (direct current).
Application around, and removal from, hazardous live conductors is
permitted.
3.5 CENELEC Directives
This instrument conforms to CENELEC Low-voltage directive 2014/35/EC,
Electromagnetic compatibility directive 2014/30/EU and RoHS directive 2011/
65/EU.
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Descriptions
4
4.1 Product Description
Figure 4.1 Product Description
1. Non-Contact Voltage Detector (NCV) antenna
2. Clamp jaws
3. Conductor alignment icon
4. Hand/finger barrier
5. Jaw opening trigger
6. Display
7. RANGE button
8. MODE /Display backlight button
9. Negative (COM) input terminal
10. Positive input terminal
11. Non-Contact Voltage detector button
12. ZERO /Relative mode button
13. Battery compartment
14. HOLD /PEAK button
15. Rotary selector switch
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Descriptions
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4.2 Control Button Descriptions
Short press to toggle AC/DC where necessary, to select an option at a mul-
ti-option rotary switch position, and to toggle ℃and ℉units in temperature
measurement mode.
Long press to toggle the display backlight ON/OFF.
Short press to change to Manual range mode, subsequent presses will step
through available ranges. Long press to return to the Auto range mode.
Short press to engage the Relative mode where subsequent measure-
ments are displayed relative to the measurement on the display at the time
of the button press (the delta relative icon appears when the Relative mode
is engaged). Long press to zero the display before taking a DC
measurement.
Short press to engage/disengage the Non-Contact Voltage Detection mode.
Short press to freeze/unfreeze displayed readings.
Long press to engage the PEAK mode. Short press to toggle between MAX
(up arrow icon appears) and MIN (down arrow icon appears). Long press to
exit the PEAK mode.
4.3 Rotary Switch Positions
Meter power is switched OFF.
Low Impedance mode.
AC Voltage mode with VFD (low pass filter).
AC Voltage mode.
DC Voltage mode.
Current mode (AC/DC).
Continuity mode.
Resistance mode.
Diode mode.
Capacitance mode.
Thermocouple temperature measurement mode.
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Descriptions
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4.4 Display Description
Figure 4.2 Display Description
1. Auto Range
2. Data hold
3. Diode mode
4. 1999 count secondary display
5. Battery status
6. Units of measure
7. 6000 count primary display
8. Relative mode
9. Low impedance mode
10. AC and DC measurement symbols
11. Continuity function
12. Low pass filter mode (VFD)
13. Peak MAX (up arrow) and Peak MIN (down arrow)
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Meter Operation
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NOTE
Before operating the device, you must read, understand, and follow all instructions, dangers,
warnings, cautions, and notes.
NOTE
When the meter is not in use, the function switch should be set to the OFF position.
NOTE
When connecting the probe leads to the device under test, connect the negative lead before
connecting the positive lead. When removing the probe leads, remove the positive lead be-
fore removing the negative lead.
NOTE
Before and after hazardous voltage measurements, test the voltage function on a known
source (such as line voltage) to determine proper meter functionality.
5.1 Powering the Meter
Set the function switch to any position to power the meter ON.
If the low battery voltage warning is displayed, or if the meter does not power
ON, replace the batteries. See Section 6, Maintenance, for battery replace-
ment details.
5.2 Auto Power OFF (APO)
The APO feature switches the meter OFF after approximately 34 minutes of
inactivity. The meter will beep to alert you when it is about to power OFF, press
the MODE button to extend the APO time. If the meter powers OFF, turn the
rotary switch to the OFF position first and then to an operational position to
switch back ON.
5.3 Automatic and Manual Ranges
The meter uses automatic ranging by default. To manually select a measure-
ment range, short press the RANGE button to exit the Auto mode. Subse-
quent, short presses will step through the available ranges. Long press the
RANGE button to return to the Auto Range mode. When the Auto Range
mode is active, the Auto Range symbol is displayed.
Figure 5.1 Auto Range Display Icon
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Meter Operation
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5.4 Out-of-Range Alert
If the input is out-of-range, OL is displayed. Please do not attempt to make
measurements beyond the specified ranges of the meter.
5.5 Display Hold Function
After taking a measurement, short press the HOLD button to freeze a reading.
Press the HOLD button again to return to normal operation. The Hicon will
appear when the display hold function is engaged.
5.6 Display Backlight
Long press the backlight button to turn ON the display backlighting. Long
press again to switch the backlight OFF. The backlight switches OFF auto-
matically after approximately 25 seconds to conserve battery energy.
5.7 AC and DC Voltage Measurements
CAUTION
Use caution when the measured voltage is greater than 30V DC or AC rms.
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Meter Operation
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Figure 5.2 AC Voltage (left) and DC Voltage (right) Measurement Setups
1. Set the function switch to the AC Voltage or DC Voltage position.
2. Insert the black test lead into the negative (COM) terminal and the red test
lead into the positive terminal.
3. Place the probe ends of the test leads in parallel to the part under test.
4. Read the Auto Range voltage measurement on the display.
5. To switch to Manual Range mode, short press the RANGE button. Subse-
quent short presses of the RANGE button will step through the available
ranges. Long press the RANGE button to return to Auto Range mode.
6. Read the frequency (Hz) of an AC signal on the upper secondary display.
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Meter Operation
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5.8 LoZ Voltage Measurements
WARNING
In LoZ mode, the input impedance increases quickly from the initial 2.5kΩ to a few hun-
dred kΩ’s on high voltage signals. Peak initial load current, while testing 1000 V AC for ex-
ample, can be as high as 566 mA (1000 V x 1.414 / 2.5kΩ), decreasing to roughly 3.37
mA (1000 V x 1.414 / 420kΩ) within a fraction of a second. Do not use LoZ mode on cir-
cuits that could be damaged by such low input impedance. Use the standard high input im-
pedance voltage modes to minimize loading on such circuits.
CAUTION
Use caution when the measured voltage is greater than 30V DC or AC rms.
LoZ Voltage measurements eliminate the affects of ‘ghost’ voltages. The pro-
cedure for taking LoZ Voltage measurements is essentially the same as for
taking standard Voltage measurements, the only difference is that for LoZ
Voltage measurements you select the LoZ rotary switch position and you must
take into consideration the effect low impedance will have on circuitry that you
test (read Warning statement above). Refer to the previous section for other
Voltage measurement details.
When you turn the rotary dial to the LoZ position, the display will show ‘auto’
indicating that the CM94 will automatically detect the measured signal as AC
or DC.
5.9 Low Pass Filter (VFD) AC Voltage Measurements
CAUTION
Use caution when the measured voltage is greater than 30V DC or AC rms.
Select the VFD mode using the rotary selector switch.
The VFD feature eliminates high frequency noise in AC voltage measure-
ments by means of a low pass filter. The VFD mode is designed for variable
frequency drive measurements. The VFD icon will appear on the display in
this mode. The procedure for taking VFD Voltage measurements is identical
to the procedure for taking standard Voltage measurements. Refer to the pre-
vious sections for Voltage measurement details.
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Meter Operation
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5.10 Current Clamp Measurements
WARNING
Do not measure current on a circuit if the voltage increases to more than 1000 V. This can
cause damage to the instrument and can cause injury to persons.
WARNING
Do not use the meter to measure current above the rated frequency. This may cause the
magnetic circuits in the jaws to reach hazardous temperatures.
WARNING
Disconnect the test leads from the meter before taking Clamp measurements.
Clamp Measurement Considerations
• Press the jaw trigger to open the jaws and then clamp around the conduc-
tor(s) of only one pole of a circuit.
• Ensure that the jaws are completely closed. Enclosing conductor(s) of
more than one pole of a circuit may result in differential current
measurements.
• Align the conductor(s) to the jaws using the conductor align icons on the
clamp jaws.
• Adjacent current-carrying devices such as transformers, motors and con-
ductor wires may affect measurement accuracy.
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Meter Operation
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Figure 5.3 AC Current (left) and DC Current (right) Measurement Setups
Taking AC or DC Current Clamp Measurements
1. Set the function switch to the Ampere position .
2. Short press the MODE button to select AC or DC current mode.
3. For DC current mode, with no conductor in the clamp, long press the
ZERO button to zero the display.
4. Press the trigger to open the clamp jaws and clamp around the conductor
under test.
5. Read the Auto Range current measurement on the display.
6. To switch to Manual Range mode, short press the RANGE button. Subse-
quent short presses of the RANGE button will step through the available
ranges. Long press the RANGE button to return to Auto Range mode.
7. Read the frequency (Hz) of an AC signal on the upper secondary display.
5.11 Resistance Measurements
WARNING
Do not perform resistance tests before removing the power to resistors and other devices
under test. Injury to persons can occur.
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