Extech Instruments MultiMaster MM560 User manual

User’s Guide
MultiMaster™ Digital MultiMeter Series
With PC Interface
Models:
MM560
MM570

1
WARRANTY
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be
free of defects in parts and workmanship for three years from date of
shipment (a six month limited warranty applies on sensors and cables). If
it should become necessary to return the instrument for service during or
beyond the warranty period, contact the Customer Service Department at
[phone] ext. 210 for authorization. A Return Authorization (RA)
number must be issued before any product is returned to Extech.
The sender is responsible for shipping charges, freight, insurance and
proper packaging to prevent damage in transit. This warranty does not
apply to defects resulting from action of the user such as misuse,
improper wiring, operation outside of specification, improper maintenance
or repair, or unauthorized modification. Extech specifically disclaims any
implied warranties or merchantability or fitness for a specific purpose and
will not be liable for any direct, indirect, incidental or consequential
damages. Extech's total liability is limited to repair or replacement of the
product. The warranty set forth above is inclusive and no other warranty,
whether written or oral, is expressed or implied.
Copyright ©2002 Extech Instruments Corporation. All rights reserved
including the right of reproduction in whole or in part in any form.
MM Series V2.2 9/03
P/N: 7M1C-0271-A000

2
Introduction
Congratulations on your purchase of Extech model MM560 or MM570
digital multimeter. Properly used, this meter will provide many years of
reliable service.
MultiMaster™ Meters provides high resolution, high accuracy, true rms
measurements of AC Voltage and Current, DC Voltage and Current,
AC+DC, Resistance, Frequency, Capacitance, Duty Cycle, dBm, Peak,
%4-20, Diode, and Continuity. The MultiMaster™ also offers RS-232 PC
Interface data acquisition capabilities as an option. Model MM570 offers
dual input Temperature measurements and very wide bandwidth.
Safety
International Safety Symbols
!Caution ! Refer to the explanation in this Manual
Caution ! Risk of electric shock
Earth (Ground)
Double Insulation or Reinforced insulation
Fuse
AC, Alternating Current or Voltage
DC, Direct Current or Voltage
AC+DC, Current or Voltage
Safety Precautions
1. Improper use of this meter can cause damage, shock, injury or death.
Read and understand this users manual before operating the meter.
2. Make sure any covers or battery doors are properly closed and
secured.
3. Always remove the test leads before replacing the battery or fuses.
4. Inspect the condition of the test leads and the meter itself for any
damage before operating the meter. Repair or replace any damage
before use.
5. To reduce the risk of fire or electric shock, do not expose this product
to rain or moisture.
6. Do not exceed the maximum rated input limits.

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7. Use great care when making measurements if the voltages are
greater than 25VAC rms or 35VDC. These voltages are considered a
shock hazard.
8. Always discharge capacitors and remove power from the device
under test before performing Capacitance, Diode, Resistance or
Continuity tests.
9. Remove the battery from the meter if the meter is to be stored for long
periods.
10. To avoid electric shock, do not measure AC current on any circuit
whose voltage exceeds 1000V AC.
11. Voltage checks on electrical outlets can be difficult and misleading
because of the uncertainty of connection to the electrical contacts.
Other means should be used to ensure that the terminals are not
"live".
12. If the equipment is used in a manner not specified by the
manufacturer, the protection provided by the equipment may be
impaired.
13. The product is intended only for indoor use.
PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY III
Equipment of OVERVOLTAGE CATEGORY III is equipment in fixed
installations.
Note – Examples include switches in the fixed installation and some
equipment for industrial use with permanent connection to the fixed
installation.
OVERVOLTAGE CATEGORY IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at the origin of
the installation.
Note – Examples include electricity meters and primary over-current
protection equipment
CENELEC Directives: These instruments conform to CENELEC low-
voltage directive 73/23/EEC and Electromagnetic compatibility directive
89/336/EEC.

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Specifications
DC VOLTAGE
Accuracy
Range MM570 MM560
500.00 mV,
5.0000V,
50.000V
0.02% + 2d 0.03% + 2d
500.00V 0.04% + 2d 0.05% + 2d
1000.0V 0.05% + 2d 0.1% + 2d
NMRR: >60dB @ 50/60Hz, CMRR: >120dB @ DC, 50/60Hz, Rs=1kΩ
Input impedance: 10MΩ, 30pF nominal (80pF nominal for 500mV range)
DC CURRENT
Range Accuracy Burden Voltage
500.00µA 0.15% + 20d 0.15mV/µA
5000.0µA 0.1% + 20d 0.15mV/µA
50.000mA 0.15% + 10d 3.3mV/mA
500.00mA 0.1% + 20d 3.3mV/mA
5.0000A 0.5% + 10d 0.03V/A
10.000A* 0.5% + 20d 0.03V/A
*10A continuous, 20A for 30 seconds max with a 5 minute cool down
interval
RESISTANCE
Accuracy
Range MM570 MM560
500.00Ω0.07% + 10d
5.0000kΩ,
50.000kΩ,
500.00kΩ
0.07% + 2d
0.1% + 6d
5.0000MΩ0.2% + 6d 0.4% + 6d
50.000MΩ2.0% + 6d 2.0% + 6d
Open circuit voltage: <1.3V (<3VDC on the 500Ωrange)

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AC & AC+DC VOLTAGE
Accuracy*
MM570 MM560
Range 20Hz to 45Hz
500.00mV,
5.0000V, 50.000V
1.5% + 40d
500.00V, 1000.0V unspecified
unspecified
45Hz to 300Hz
500.00mV 0.3% + 20d
5.0000V, 50.000V 0.8% + 20d
500.00V, 1000.0V 0.4% + 40d
0.8% + 60d
300Hz to 5kHz 300Hz to 1kHz
500.00mV 0.3% + 10d 0.8% + 40d
5.0000V, 50.000V,
500.00V
0.4% + 40d 2.0% + 60d
1000.0V 0.8% + 40d
(300Hz-1kHz)
1.0% + 40d
5kHz to 20kHz 1kHz to 20kHz
500.00mV 0.5% + 20d 1dB**
5.0000V, 50.000V 0.8% + 20d 2dB**
500.00V 0.5% + 20d 3dB**
1000.0V Unspecified Unspecified
20kHz to 100kHz
500.00mV 2.0% + 40d
5.0000V, 50.000V 4.0% + 40d**
500.00V, 1000.0V Unspecified
Unspecified
*From 5% to 10% of range: accuracy % of reading (or in dB) + 80digits
**From 5% to 10% of range: accuracy % of reading (or in dB) +180digits
**From 10% to 15% of range: accuracy % of reading (or in dB) +100digits
CMRR: >90dB @ DC to 60Hz, Rs=1kΩ
Input Impedance: 10MΩ, 30pF nominal (80pF nominal for 500mV range)
Residual reading less than 50 digits with test leads shorted

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AC & AC+DC CURRENT
Accuracy
MM570 MM560
Range 50Hz to 60Hz Burden Voltage
500.00µA,
5000.0µA
0.15mV/µA
50.000mA,
500.00mA
3.3mV/mA
5.0000A,
10.000A*
0.5% + 50d 1.0% + 40d
0.03V/A
40Hz to 1kHz
500.00µA,
5000.0µA
0.15mV/µA
50.000mA,
500.00mA
3.3mV/mA
5.0000A,
10.000A*
0.7% + 50d 1.0% + 40d
0.03V/A
1kHz to 10kHz
500.00µA,
5000.0µA
0.15mV/µA
50.000mA,
500.00mA
2.0% + 50d
3.3mV/mA
5.0000A,
10.000A*
Unspecified
Unspecified
0.03V/A
*10A continuous, 20A for 30 seconds max with a 5 minute cool down
interval
TEMPERATURE; T1, T2 DUAL (MM570 ONLY)
Range Accuracy*
-50.0°C TO 1000.0°C 0.3% + 1oC
-58.0°F TO 1832.0°F 0.3% + 2oF
*Thermocouple range and accuracy not included

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CAPACITANCE
Range Accuracy*
50.00nF, 500.0nF 0.8% + 3d
5.000µF 1.0% + 3d
50.00µF 2.0% + 3d
500.0µF 3.5% + 5d
9999µF 5.0% + 5d
*Accuracies with film capacitor or better
FREQUENCY, AC LINE LEVEL
Range 5.0000Hz to 200.000kHz
Accuracy 0.002% + 4d
500mV range 0.1V min
5V range 1V min
50V range 10V min
500V range 100V min
Sensitivity
1000V range 900V min
FREQUENCY, LOGIC LEVEL
Range 5.0000Hz to 2.00000MHz
Accuracy 0.002% + 4d
Sensitivity 2.5Vp square wave
% DUTY CYCLE
Range 0.10% to 99.99%
Accuracy 3d/kHz + 2d
Input Frequency 5Hz-500kHz, 5V logic family
dBm
Range -11.76dBm to 54.25dBm (@ 600Ω)
Accuracy 0.25dB + 2d (@40Hz to 20kHz)
Reference Impedance Selectable: 4, 8, 16, 32, 50, 75,93, 110, 125,
135, 150, 200, 250, 300, 500, 600, 800, 900,
1000, 1200Ω
*Input impedance 10MΩ, 30pF nominal

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DC Loop Current %4 to 20mA:
4mA = 0% (zero), 20mA = 100% (span), Resolution: 0.01%, Accuracy:
±25d
Diode Test:
Accuracy: 1%+1d, Current 0.8mA(typical), Open circuit: <3.5VDC
Peak Capture (Instantaneous Peak Hold):
Accuracy: Specified accuracy ±100 digits for changes > 0.8ms in
duration
Audible Continuity:
Measurement threshold: Between 20Ωand 200Ω, response time:
<100µs
Accuracy Notes: Accuracy is ± (% reading + number of digits), or as
otherwise specified, at 23°C ±5°C < 75% R.H. True RMS accuracies
are specified from 5% to 100% of range or as otherwise specified.
Maximum Crest Factor <5:1 at full scale & <10:1 at half scale with
frequency component within the specified frequency bandwidth for non-
sinusoidal waveforms.
Sensing: DC, AC True RMS, AC+DC True RMS
Digital Display: 4-4/5 digits, 50000 count
5-4/5 digits, 500000 count for DCV
6 digits, 999999 count for Hz
Bar Graph Display: 42-segment bargraph
Polarity: Automatic
Update rate: 5 /second for 50,000 count display (fast mode), 1.25
/second for 500,000 count display (stable mode)
60 per second for bar graph display
Low Battery: Below approx. 7V
Operating Temperature: 41°to 104°F (5°to 40°C)
Storage Temperature: -4°to 140°F (-20 to 60oC
Relative Humidity: Max 80% up to 87ºF (31ºC) decreasing linearly
to 50% at 104ºF(40ºC): <80% storage
Operating Altitude: Below 2000 meters
Temp. Coefficient: Nominal 0.1x(specified accuracy)/ oC @(0oC to 18oC
or 28oC to 40oC), or otherwise specified
Power Supply: 9V battery (NEDA1604, JIS006P or IEC6F22)
Power Consumption: 5mA typical

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Auto Power Off: After 17 minutes of inactivity with no input signal.
Power consumption during auto power off; 20µA
Safety: The MultiMaster™ Series meters are intended for indoor
use and are protected, against the users, by double
insulation per EN61010-1 and IEC61010-1 2nd Edition
(2001) to CAT III 1000V & CAT IV 600V. The meter (all
versions) also meets UL3111-1(1994)* and CSA C22.2 No.
1010-1-92* to CAT III 1000V.
MM560 Terminals (to COM) ratings:
V : CATEGORY III 1000 VOLTS AC & DC, AND
CATEGORY IV* 600 VOLTS AC & DC.
A / mAµA : CATEGORY III AND CATEGORY IV* 500
VOLTS AC AND 300 VOLTS DC.
MM570 Terminals (to COM) ratings:
V/A/uAmA: CATAGORY III 1000 Volts and CATAGORY IV*
600V AC & DC
*Category IV safety standard (for DMMs) was first released in
IEC61010-1 2nd Edition in year 2001, and was yet an UL published
standard at the time this manual was written.
E.M.C.: Meets EN61326(1997, 1998/A1), EN61000-4-2(1995) and
EN61000-4-3(1996). Also meets former standards EN55011
(1991) and EN50082-1(1997)
In an RF field of 3V/m: Capacitance function is not specified
Other function ranges: Total Accuracy = Specified Accuracy +
30 digits. Performance above 3V/m is not specified
Overload Protection:
µA/mA:0.63A/500V F, IR 200kA, fuse for MM560
1A/1000V F, IR 10kA (acceptable alternative;
0.44A/1000V IR 10kA) fuse for MM570
A : 12.5A/500V F, IR 20kA, for MM560
15A/1000V F, IR 10kA (acceptable alternative; 11A/1000V
IR 20kA) fuse for MM570
V, Ωother: 600VDC/VAC for MM560
1050V rms, 1450V peak for MM570
Transient Protection 8kV (1.2/50µs surge)
Dimension: 7.32 x 3.43 x 1.4" with holster (186mm x 87mm x 35.5mm)
Weight: 15.17 oz. with holster (430g)

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Meter Description (MM570 Shown)
1. Liquid Crystal display
2. Function push-keys
3. Rotary function switch
4. 10A/-T2 input jack
5. V/Hz/Ω/Cap/+T1 input jack
6. COM input jack/-T1 input
7. mA-uA current/+T2 input jack
NOTE: RS-232 Optical interface is located
on the top rear of the meter.
Considerations & Features
Average sensing RMS calibrated
RMS (Root-Mean-Square) is the term used to describe the effective or
equivalent DC value of an AC signal. Most digital multimeters use
average sensing RMS calibrated technique to measure RMS values of
AC signals. This technique is to obtain the average value by rectifying
and filtering the AC signal. The average value is then scaled upward
(calibrated) to read the RMS value of a sine wave. In measuring pure
sinusoidal waveform, this technique is fast, accurate, and cost effective.
In measuring non-sinusoidal waveforms, however, significant errors can
be introduced because of different scaling factors relating average to
RMS values.
AC True RMS
AC True RMS, normally referred to as True RMS, identifies a DMM
function that is AC coupled, and responds accurately only to the
effective RMS AC component value regardless of the waveforms.
However, DC component plays an important role in the distorted non-
symmetrical waveforms, and will also be of interest sometimes. A full
wave rectified sine waveform is a good example, and the AC true RMS
function will only give the AC component reading which is at 43.6% of
the total effective RMS reading.

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DC+AC True RMS
DC+AC True RMS calculates both of the AC and DC components given
by the expression when making measurement, and
can responds accurately to the total effective RMS value regardless of
the waveform. Distorted waveforms with the presence of DC
components and harmonics may cause:
1) Overheated transformers, generators and motors to burn out faster
than normal
2) Circuit breakers to trip prematurely
3) Fuses to blow
4) Neutrals to overheat due to the triplen harmonics present on the
neutral
5) Bus bars and electrical panels to vibrate
AC Bandwidth
AC bandwidth of a DMM is the range of frequencies over which AC
measurements can be made within the specified accuracy. It is not the
frequency measurement function, and is the frequency response of the
AC functions. A DMM cannot accurately measure the AC value with
frequency spectrums beyond the AC bandwidth of the DMM. Therefore,
wide AC bandwidth plays an important role in a high performance DMM.
In reality, complex waveforms, noise and distorted waveforms contain a
much higher frequency spectrum than its fundamental.
NMRR (Normal Mode Rejection Ratio)
NMRR is the DMM's ability to reject unwanted AC noise effect that can
cause inaccurate DC measurements. NMRR is typically specified in
terms of dB (decibel). This series has a NMRR specification of >60dB at
50 and 60Hz, which means a good ability to reject the effect of AC noise
when making DC measurements.
CMRR (Common Mode Rejection Ratio)
Common mode voltage is voltage present on both the COM and
VOLTAGE input terminals of a DMM, with respect to ground. CMRR is
the DMM's ability to reject common mode voltage effects that can cause
digit rattle or offset in voltage measurements. This series has a CMRR
specifications of >90dB at DC to 60Hz in ACV function; and >120dB at
DC, 50 and 60Hz in DCV function. If neither a NMRR nor a CMRR
specification is specified, a DMM's performance will be uncertain.

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Analog bar-graph
The analog bar graph provides a visual indication of measurement like a
traditional analog meter needle. It is excellent in detecting faulty
contacts, identifying potentiometer clicks, and indicating signal spikes
during adjustments.
Default Functions
The Multimaster™ will set the function last used as the default function.
For example, if dBm is last used in the VAC position, the meter will
display dBm the next time that function is selected.
Backlit display
The MultiMaster™ series multimeters are equipped with a backlight for
viewing the LCD display in poorly lit areas.
Data Hold
The HOLD function freezes the reading on the display for later viewing.
Manual and Automatic Ranging
The MultiMaster™ series multimeters are Autoranging, with manual
override.
Smart Power Auto Power Off (APO)
Smart Power automatically shuts the meter down after approximately 17
minutes of inactivity. APO can be disabled on power up and is also
disabled if a signal is present.
Audible Beeper
The audible beeper confirms a keystroke. It can be disabled.
MAX/MIN mode
MAX/MIN mode stores the minimum and maximum readings in memory
for later viewing.
Relative mode
Relative mode allows the meter to display the difference between the
actual measurement and a stored reference value.
PeakCcapture mode
PeakC captures voltage or current signals that have durations as short
as 0.8ms. This mode is available in DCV, ACV, DCA, & ACA functions.
Sealing
The meter is sealed using an o-ring and gasket to prevent moisture and
dust from entering.
Rubber Holster
The heavy duty rubber holster provides drop resistance, good grip and
can be removed and washed if necessary.

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Operation
Measurement Considerations
NOTICE: Read and understand all warning and caution statements
listed in the safety section of this operation manual prior to using this
meter.
1. Always move the rotary function switch to the OFF position when the
meter is not in use. This meter has Auto Power OFF that
automatically shuts the meter OFF if 17 minutes elapse without
activity.
2. If "OL" appears on the display during a measurement, the
measurement exceeds the range selected. Change to a higher range.
AC, DC or AC+DC Voltage Measurements
1. Insert the black test lead into the negative COM jack and the red test
lead into the positive Vjack.
2. Set the function switch to the "VAC", "VDC" or "mV" position
3. In “VAC” press the SELECT key to toggle between AC and dBm.
4. In “VDC”press the SELECT key to toggle between DC and AC+DC.
5. In “mV” press the SELECT key to toggle between DC, AC and
AC+DC.
6. Read the voltage measurement on the display.
7. Press the 500000 key momentarily to toggle between 50,000 counts
and 500,000 counts in DCV or DC mV.
Note: The setting selected will be stored in non-volatile memory and will
become the default setting.
dBm Measurements
1. Set up and connect as described for ACV measurements.
2. Press the SELECT key momentarily to select dBm.
3. The reference impedance will be displayed for 1 second before the
dBm display appears.
4. Press the RANGE key momentarily to change the reference
impedance.
AC or DC Current Measurements
CAUTION: Do not make current measurements at 20A for longer than
30 seconds. Exceeding 30 seconds may cause damage to the meter
and/or the test leads.
1. Insert the black test lead into the negative COM jack.

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2. For current measurements up to 5000µA, set the function switch to
the "µA" position and insert the red test lead into the mA-µAjack.
3. For current measurements up to 500mA, set the function switch to the
"A/mA" position and insert the red test lead into the mA-µAjack.
4. For current measurements up to 10A, set the function switch to the
"A/mA" position and insert the red test lead into the 10A jack.
5. Press the SELECT key momentarily to toggle between DC, AC and
AC+DC
6. Remove power from the circuit under test and open the circuit at the
point where you wish to measure current.
7. Touch the black test probe tip to the negative side of the circuit and
touch the red test probe tip to the positive side of the circuit.
8. Apply power to the circuit.
9. Read the current on the display
CAUTION: When measuring a 3-phase system, special attention should
be taken to the phase to phase voltage which is significantly higher than
the phase to earth voltage. To avoid accidentally exceeding the voltage
rating of the protection fuse(s), always consider the phase to phase
voltage as the working voltage for the protection fuse(s).
% 4 – 20mA Measurements
1. Set up and connect as described for DC mA measurements.
2. Press and hold the %4-20mA key for 1 second.
3. The meter will display loop current as a % with 4mA = 0% and 20mA
= 100%
Resistance and Continuity Measurements
CAUTION: Using the resistance or continuity function in a live circuit will
produce false readings and may damage the meter. Always remove
power and isolate the component from the circuit to obtain an accurate
reading.
1. Insert the black test lead banana plug into the negative COM jack and
the red test lead banana plug into the Ωjack.
2. Set the function switch to the "Ω" position.
3. Press the SELECT key momentarily to select Continuity.
4. Touch the test probe tips across the circuit or part under test. It is best
to disconnect one side of the part under test so the rest of the circuit
will not interfere with the resistance reading.
5. For Resistance tests, read the resistance on the display.

15
6. For Continuity tests, if the resistance is less than the threshold (20Ω
to 200Ω), an audible tone will sound.

16
Capacitance Measurements
1. Insert the black lead into the negative COM jack and the red test lead
into the positive CAP jack.
2. Set the function switch to the " CAP" position.
3. Press the SELECT key momentarily to select Capacitance
4. Touch the test leads to the capacitor to be tested and read the
measured value.
Line Frequency Measurements
1. Connect and make a voltage or current measurement as described in
the previous paragraphs.
2. Press the Hz key to select the Frequency (Hz) function.
3. Read the frequency on the display
Notes on sensitivity:
The input sensitivity varies automatically with voltage (or current)
range selected. The lower the measuring range, the higher the
sensitivity. It is recommended to first measure the voltage (or current)
level then activate the Hz function in that voltage (or current) range to
automatically get the most appropriate trigger level. When activated
from voltage function, you can also press the RANGE key
momentarily to select another trigger level range manually. The
analog bargraph pointer will point at the selected trigger level range
scale 1, 2, 3, or 4. If the Hz reading is unstable, select lower
sensitivity to avoid electrical noise. If the reading shows zero, select a
higher sensitivity.
Logic Level Frequency Measurements
1. Insert the black lead into the negative COM jack and the red test lead
into the positive Vjack.
2. Set the function switch to the “Hz” position.
3. Press the SELECT key momentarily to select Hz
4. Read the frequency on the display
5. Press the 500000 key momentarily to toggle between 5 full digits and
6 full digits display.
% Duty Cycle
1. Insert the black lead into the negative COM jack and the red test lead
into the positive Vjack.
2. Set the function switch to the “Hz” position.
3. Press the SELECT key momentarily to select %
4. Read the %duty cycle on the display

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Diode Test
1. Insert the black lead into the negative COM jack and the red test lead
into the positive CAP jack
2. Set the function switch to the " CAP" position.
3. Press the SELECT key momentarily to select the diode function
4. Touch the test probe tips to the diode or semiconductor junction you
wish to test. Note the meter reading.
5. Reverse the test lead polarity by reversing the red and black leads.
Note this reading.
6. The diode or junction can be evaluated as follows:
a. If one reading displays a value and the other reading displays "OL",
the diode is good.
b. If both readings display "OL", the device is open.
c. If both readings are very small or 0, the device is shorted.
Temperature Measurements (MM570 only)
1. Insert the T1 Temperature Probe into the COM and TEMP input jacks
observing polarity.
2. Insert the T2 Temperature Probe into the 10A and mA-µAinput jacks
observing polarity
3. Set the function switch to the "TEMP" position.
4. Use the SELECT key to toggle between oC and oF.
5. Use the RANGE key to toggle between T1, T2 and T1-T2.
6. Touch the Temperature Probe tip to the device under test.
7. Wait 30 seconds for the measurement to stabilize and then read the
display.
MAX/MIN
Press the MAX/MIN key momentarily to activate MAX/MIN recording
mode. The LCD anunciators “R” and “MAX MIN” turn on. The meter
beeps when a new maximum or minimum reading is updated. Press the
key momentarily to step through the Maximum (MAX), Minimum (MIN),
and Maximum minus Minimum (MAX - MIN) readings. Press the key for
1 second or more to exit MAX/MIN recording mode. Auto Power Off
feature will be disabled automatically in this mode.

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Relative mode
Relative Zero allows the user to offset the meter by using the displayed
value as the zero reference value. Practically all of the displayed
readings can be set as the relative reference value including the
MAX/MIN recording feature. Press the key momentarily to activate
and to exit Relative Zero mode.
Peak Ccapture mode
Press PEAK key momentarily to activate the mode to capture voltage or
current signal duration as short as 0.8ms. This mode is available in DC,
AC, DC+AC modes of voltage and current functions. The LCD
annunciators “C” & “MAX” turn on. The meter beeps when a new
maximum or minimum reading is updated. Press the key momentarily to
read throughout the Maximum (MAX), Minimum (MIN), and Maximum -
Minimum readings. Press the key for 1 second or more to exit PEAK
capture mode. Auto Power Off feature will be disabled automatically in
this mode.
Smart Power Auto Power Off
Smart Power shuts the meter down automatically after approximately 17
minutes of inactivity. The 17-minute time period is reset any time the
rotary switch is moved or as long as a signal is being fed into the meter
is greater than 10% of the range. This prevents auto powering off during
long-term tests. To wake the meter, press the MAX/MIN key or turn the
meter off and on again.
Disabling Auto Power Off
Press the RANGE key while turning the meter on to disable the Auto
Power Off feature. Auto power off is also disabled in the MAX/MIN and
Peak modes.
Audible Beeper
The audible beeper can be disabled by pressing the Hz key while
turning the meter on.
Backlighted display
Press the SELECT key for 1 second or more to turn on or off the display
backlight function. The backlight will automatically turn off after 30
seconds.
Hold H
The hold function freezes the reading in the display. Press the HOLD H
key momentarily to activate or to exit the hold function

19
RS-232 PC Interface
This instrument is equipped with an optically isolated interface port
(located on the rear of the meter). An optional WindowsTM software and
interface package is available for data acquisition applications. This
optional kit is required to connect the meter to a PC. The software
provides digital, analog, and graphical data displays. Refer to the
README file in the interface kit for further details.
Maintenance
WARNING: To avoid electrical shock, disconnect the meter from any
circuit, remove the test leads from the input jacks and turn OFF the
meter before opening the case. Do not operate with open case. Install
only the same type of fuse or equivalent
Cleaning and Storage
Periodically wipe the case with a damp cloth and mild detergent; do not
use abrasives or solvents. If the meter is not to be used for periods of
longer than 60 days, remove the battery and store it separately
Battery Replacement
Loosen the 2 screws from the battery access door of the case bottom. Lift
the battery access door and thus the battery compartment up. Replace
the battery. Re-fasten the screws.
Battery: Standard 9V Alkaline (NEDA1604, JIS006P, IEC6F22)