Greenlee CM-600 User manual

INSTRUCTION MANUAL
Read and understand all of the instructions and safety information in this
manual before operating or servicing this tool.
CM-600 • CM-650
Clamp-on Meters
99945550 © 2008 Greenlee Textron Inc. IM 1520 REV 2 10/08

2
Description
The Greenlee CM-600 and CM-650 Clamp-on Meters are versatile clamp-on meters intended to
measure AC current, AC voltage, resistance and to verify continuity. These units also have data hold
capability. In addition, the CM-650 is a true RMS reading meter.
Safety
Safety is essential in the use and maintenance of Greenlee tools and equipment. This instruction
manual and any markings on the tool provide information for avoiding hazards and unsafe practices
related to the use of this tool. Observe all of the safety information provided.
Purpose of This Manual
This instruction manual is intended to familiarize all personnel with the safe operation and maintenance
procedures for the Greenlee CM-600 and CM-650 Clamp-on Meters.
Keep this manual available to all personnel.
Replacement manuals are available upon request at no charge at www.greenlee.com.
Do not discard this product or throw away!
For recycling information, go to www.greenlee.com.
All specifications are nominal and may change as design improvements occur. Greenlee Textron Inc. shall not be liable
for damages resulting from misapplication or misuse of its products.
® Registered: The color green for electrical test instruments is a registered trademark of Greenlee Textron Inc.
KEEP THIS MANUAL

CM-600 • CM-650
3
SAFETY ALERT SYMBOL
This symbol is used to call your attention to hazards or unsafe practices which could result in an
injury or property damage. The signal word, defined below, indicates the severity of the hazard.
The message after the signal word provides information for preventing or avoiding the hazard.
Immediate hazards which, if not avoided, WILL result in severe injury or death.
Hazards which, if not avoided, COULD result in severe injury or death.
Hazards or unsafe practices which, if not avoided, MAY result in injury or property damage.
Read and understand this material before operating or servicing this
equipment. Failure to understand how to safely operate this tool could result in
an accident causing serious injury or death.
Important Safety Information

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Important Safety Information
Electric shock hazard:
Contact with live circuits could result in severe injury or death.
Electric shock and fire hazard:
Do not expose this unit to rain or moisture.•
Do not use the unit if it is wet or damaged.•
Use test leads or accessories that are appropriate for the application. Refer to the category and•
voltage rating of the test lead or accessory.
Inspect the test leads or accessory before use. They must be clean and dry, and the insulation•
must be in good condition.
Use this unit for the manufacturer’s intended purpose only, as described in this manual. Any other•
use can impair the protection provided by the unit.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
Verify that the unit is not in hold mode before making a measurement. The unit may be in hold•
mode when turned on. Hold mode is not affected by turning the unit off or by changing the position
of the selector.
Do not apply more than the rated voltage between any two input terminals, or between any input•
terminal and earth ground.
Do not contact the test lead tips or any uninsulated portion of the accessory.•
Failure to observe these warnings could result in severe injury or death.

CM-600 • CM-650
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Important Safety Information
Electric shock hazard:
Do not operate with the case open.•
Before opening the case, remove the test leads (or jaw) from the circuit and shut off the unit.•
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
Unless measuring voltage, current, or frequency, shut off and lock out power. Make sure that all•
capacitors are discharged. Voltage must not be present.
Using this unit near equipment that generates electromagnetic interference can result in unstable•
or inaccurate readings.
Failure to observe these warnings could result in severe injury or death.
Electric shock hazard:
Do not change the measurement function while the test leads are connected to a component or
circuit.
Failure to observe this precaution may result in injury and can damage the unit.
Electric shock hazard:
Do not attempt to repair this unit. It contains no user-serviceable parts.•
Do not expose the unit to extremes in temperature or high humidity. Refer to “Specifications.”•
Failure to observe these precautions may result in injury and can damage the unit.
Set the selector and connect the test leads so that they correspond to the intended measurement.
Incorrect settings or connections can result in a blown fuse.

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Identification
1. Display
2. Selector
3. Lever
4. Jaw
5. Hold button
6. COM terminal
7. V-Ω terminal
8. Battery Cover
9. Battery Cover Screw
Symbols on the Unit
Warning—Read the instruction manual
Double insulation
Battery
5
6
4
2
1
7
3
9
8
Front Back
Display Icons
10. Hold function is enabled.
11. — Polarity Indicator
12. Low Battery
13. l Overload Indication
10
11
12
13

CM-600 • CM-650
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AC Measurement
AC measurements are usually displayed as RMS (root mean squared) values. Two methods of AC
measurement are average-responding RMS calibrated and true RMS-reading.
The average-responding RMS calibrated method takes the average value of the input signal, multiplies
it by 1.11, and displays the result. This method is accurate if the input signal is a pure sine wave. The
Greenlee CM-600 is an average-responding meter.
The true RMS-reading method uses internal circuitry to read the true RMS value. This method is
accurate, within the specified crest factor limitations, whether the input signal is a pure sine wave, a
square wave, sawtooth, half wave or signal with harmonics. The ability to read true RMS provides much
more measurement versatility. The Greenlee CM-650 is a true RMS meter.
The Waveforms and Crest Factors table shows some typical AC signals and their RMS values.
Waveforms and Crest Factors
Waveform
RMS Value 100 100 100 100
Average Value 90 100 87 64
Crest Factor*
(ξ)1.414 1 1.73 2
* The crest factor is the ratio of the peak value to the RMS value; it is represented by the Greek
letter ξ.

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Operation
Electric shock hazard:
Do not contact live circuits.•
Verify that the unit is not in hold mode before making a measurement.•
Failure to observe these warnings could result in severe injury or death.
1. Set the selector according to the Settings Table.
Settings Table
To measure
this value …
set the selector
to this symbol …
connect the
red lead to …
and connect the
black lead to …
AC Voltage V-Ω COM
AC Current
(200 A max.) N/A N/A
AC Current
(200 A to 600 A) N/A N/A
Continuity V-Ω COM
Resistance* V-Ω COM
* Tone indicates circuit resistance is less than 50 Ω.
2. Refer to “Typical Measurements” for specific measurement instructions.
3. Test the unit on a known functioning circuit or component.
If the unit does not function as expected on a known functioning circuit, replace the battery.•
If the unit still does not function as expected, send the unit to Greenlee for repair. Refer to the•
instructions under the Warranty.
4. Verify that the unit is not in hold mode, and then take the reading from the circuit or component to
be tested.
5. Press HOLD to hold the measured value on the display. Press HOLD again to exit hold mode.
Auto Power Off
When the meter is powered on, a timer is activated that will turn the unit off after approximately 30
minutes. To continue making measurements after the unit automatically powers off, switch the selector
to OFF and then back to the desired function.

CM-600 • CM-650
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Typical Measurements
Clamp Around Wire
Notes:
Clamp the jaw around one conductor only.•
Close the jaw completely.•
Center the wire in the jaw for highest accuracy.•
Clamp Around Line Splitter
Notes:
The Greenlee 93-30 Line Splitter is divided.•
One section renders amps; the other
renders amps multiplied by 10.
Close the jaw completely.•
Center the line splitter in the jaw for•
highest accuracy.

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Accuracy
Accuracy is specified as follows: ± (a percentage of the reading + a fixed amount)
at 23 °C ± 5 °C (73.4 °F ± 9 °F), 0% - 75% relative humidity.
Refer to the “Specifications” section for operating conditions.
Value Range Accuracy Frequency
Range
Input
Impedance
AC Voltage 0 to 600 V ± (1.2% + 3 V) 40 to 500 Hz 2 MΩ
2 nF
AC Current
(200 A range) 0 to 199.9 A ± (1.9% + 0.5 A) 50/60 Hz N/A
AC Current
(600 A range)
0 to 400 A ± (1.5% + 5 A) 50/60 Hz N/A
400 to 600 A ± (2.5% + 5 A) 50/60 Hz
Resistance* 0 to 2000 Ω ± (1.5% + 2 Ω) N/A N/A
* Maximum open circuit voltage: 1 V
Continuity
Threshold: Tone sounds if the measured resistance is less than approximately 50 Ω,
and turns off when greater than approximately 300 Ω.
For the CM-600, AC accuracy is specified for sine waves only.
For the CM-650, accuracy specification applies for waveforms with crest factors less than 2.
For crest factors from 2 to 3, add 1.4% to accuracy.•
For crest factors from 3 to 4, add 3% to accuracy.•