Greenlee CMI-100 User manual

999 3269.5 © 1999 Greenlee Textron IM 1413 8/99
CMI-100
CLAMP-ON METER
AMPERÍMETRO
CON PINZA
COMPTEUR
A PINCES
INSTRUCTION MANUAL
MANUAL DE INSTRUCCIONES
MANUEL D’INSTRUCTIONS
Read and understand all of the instructions and safety
information in this manual before operating or servicing this tool.
Lea y entienda todas las instrucciones y la información sobre
seguridad que aparecen en este manual, antes de manejar estas
herramientas o darles mantenimiento.
Lire attentivement et bien comprendre toutes les instructions et
les informations sur la sécurité de ce manuel avant d’utiliser ou de
procéder à l’entretien de cet outil.

2
Description
The Greenlee CMI-100 Clamp-on Meter is a hand-held testing device with the following
measurement capabilities: AC and DC voltage, AC and DC current, frequency and resistance.
The unit is also intended to check diodes and verify continuity.
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
This instruction manual is intended to familiarize all personnel with the safe operation and
maintenance procedures for the Greenlee CMI-100 Clamp-on Meter.
Keep this manual available to all personnel.
Replacement manuals are available upon request at no charge.
and are registered trademarks of Greenlee Textron.
KEEP THIS MANUAL

CMI-100
3
Important Safety Information
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.
SAFETY ALERT SYMBOL
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 can result in an accident causing serious injury or death.
Electric shock hazard:
Contact with live circuits can result in severe injury or death.

4
Important Safety Information
Electric shock hazard:
• Do not use the unit if it is wet or damaged.
• Use test leads or accessories that are appropriate for the application. See the
category and voltage rating of the test lead or accessory.
• Inspect the test leads or accessory before use. The item(s) must be clean and dry,
and the insulation must be in good condition.
Failure to observe these warnings can result in severe injury or death.
Electric shock hazard:
• 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 can result in severe injury or death.
• 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 can result in severe injury or death.

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Important Safety Information
Do not change the measurement function while the test leads are connected to a
component or circuit.
Failure to observe this precaution can result in injury and can damage the instrument.
• 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.
See Specifications.
Failure to observe these precautions can result in injury and can damage the unit.
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.
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.

6
Identification
1. Display
2. Lever
3. Jaw
4. Selector
5. HOLD Button
6. MAX/MIN Button
3
1
6
7
2
4
8
5
11
9 10
7. RANGE Button
8. ∆ZERO Button
9. COM Terminal
10. + Terminal
11. Polarity Indicator for DC
Current Measurements

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Display Icons
11. Manual Ranging is enabled.
12. – Polarity Indicator for
Digital Display
13. AUTO Automatic Ranging is enabled.
14. Low Battery
15. DC measurement is selected.
16. AC measurement is selected.
17. ∆Relative mode is enabled.
18. Hold function is enabled.
19. MAX MAX Hold function is enabled.
20. MIN MIN Hold function is enabled.
21. M Mega (106)
Symbols on the Unit
Read the instruction manual.
Double Insulation
Battery
22. K Kilo (103)
23. ΩOhms
24. Hz Hertz
25. Continuity
26. Diode
27. m Milli (10-3)
28. V Volts
29. A Amps
30. 4 Overload for Digital Display
31. Overload for Bar Graph
32. Bar Graph Element
33. – Polarity Indicator for Bar Graph
25
26
27–29
21–24
16 17 18 19 20
11
12
13
14
15
3230 3133

8
*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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AC Measurement
AC measurements are usually displayed as RMS (root mean squared) values. Two types of AC
measurement method 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 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 wave, half wave or signal with harmonics. The ability to read
true RMS provides much more measurement versatility. The Greenlee CMI-100 is a true RMS
meter.
The Waveforms and Crest Factors table shows some typical AC signals and their RMS values.
Waveforms and Crest Factors

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Using the Features
•RANGE Press once to enter the manual ranging mode. The AUTO icon will disappear
from the display. Press repeatedly to step through the ranges. Press and hold to return to
the automatic ranging mode.
Note: The autoranging feature is not available in the MAX/MIN and ∆ modes.
•MAX/MIN (PEAK) Holds the minimum or maximum value on the display. Since this feature
only operates with manual ranging, press the RANGE button first to select the
appropriate range, as described above. Press once to hold the minimum value; press again
to hold the maximum value (or peak value, if measuring an AC signal). Press again to exit
this mode.
•∆ZERO Finds the difference between two measurements. While taking a measurement,
press ∆to set the display to zero. The ∆icon will appear on the display. Take the second
measurement. The value on the display will be the difference between the two measure-
ments. Press and hold to exit this mode.
•HOLD Press momentarily to hold the present value on the display. Press again to exit
this mode.

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Operation
Electric shock hazard:
Contact with live circuits can result in severe injury or death.
1. Set the selector according to the Settings Table and connect the test leads to the unit.
Start with the highest measurement range.
Settings Table
To measure set the selector this icon will appear connect the and connect the
this value … to this symbol … on the display … red lead to … black lead to …
Continuity** and Ω+ COM
Current (AC) Aand A N/A N/A
Current (DC) Aand press and A N/A N/A
∆ZERO
Diode and press and V + COM
the RANGE button
Frequency* Hz and press Hz + COM
the RANGE button
Resistance Ω+ COM
Voltage (AC) Vand V + COM
Voltage (DC) Vand V + COM
*Frequency can also be measured with the jaw. Current flow must be at least 5 amps for an
accurate frequency reading.
**Tone indicates circuit resistance is less than 40 Ω.
2. See Typical Measurements for illustrations of typical uses.
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.
4. Take the reading from the circuit to be tested.