RS PRO RS-927A User manual

Instruction Manual
RS-927A
Stock No: 264-7228
True RMS Autoranging Digital Multimeter
EN
Africa
RS Components SA
P.O. Box 12182,
Vorna Valley, 1686
20 Indianapolis Street,
Kyalami Business Park,
Kyalami, Midrand
South Africa
www.rs-components.com
Asia
RS Components Ltd.
Suite 1601, Level 16, Tower 1,
Kowloon Commerce Centre,
51 Kwai Cheong Road,
Kwai Chung, Hong Kong
www.rs-components.com
China
RS Components Ltd.
Unit 501, Building C, The
New Bund World Trade Center
Phase II, Shanghai, China
www.rs-components.com
United Kingdom
RS Components Ltd.
PO Box 99, Corby,
Northants.
NN17 9RS
United Kingdom
www.rs-components.com
Japan
RS Components Ltd.
West Tower (12th Floor),
Yokohama Business Park,
134 Godocho, Hodogaya,
Yokohama, Kanagawa 240-0005
Japan
www.rs-components.com
U.S.A
Allied Electronics
7151 Jack Newell Blvd. S.
Fort Worth,
Texas 76118
U.S.A.
www.alliedelec.com
South America
RS Componentes Limitada
Av. Pdte. Eduardo Frei M. 6001-71
Centro Empresas El Cortijo
Conchali, Santiago, Chile
www.rs-components.com
Europe
RS Components GmbH
Mainzer Landstraße 180
60327 Frankfurt am Main
Germany

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True RMS Autoranging Digital Multimeter / English
1.Introduction
• The meter measures AC/DC Voltage, AC/DC Current , Resistance, Diode Test, Continuity
Capacitance, Frequency and Temperature.
• The meter also offers a Non-Contact AC Voltage detector.
• Proper use and care of this meter will provide many years of reliable service.
2. Safety
2-1. WARNINGS
• Read, understand and follow Safety Rules and Operating lnstructions in this manual before
using this meter.
• The meter's safety features may not protect the user if not used in accordance with the
manufacturer's instructions.
• Keep fingers away from the metal probe tips when taking measurements.
• Before changing functions using the selector switch, always disconnect the test leads from
the circuit under test.
• Comply with all applicable safety codes, Use approved personal protective equipment when
working near live electrical circuits - particularly with regard to arc-flash potential.
• Use caution on live circuits, Voltages above 30V AC rms, 42V AC peak or 60V DC pose a
shock hazard.
• Do not use if the meter or test leads appear damaged.
• Verify operation before using meter by measuring a known live voltage.
• Do not use the meter in wet or damp environments or during electrical storms.
• Do not use the meter or near explosive vapors, dust or gasses.
• Do not use the meter if it operates incorrectly, protection may be compromised.
• Do not operate meter while Low Battery warning is on, replace batteries immediately.
• Do not apply voltage or current that exceeds the meter's maximum rated input limits.
2-2.lnput Limits
Function Maximum Input
Voltage AC or DC 600V AC/DC
Frequency, Resistance, Capacitance,
Continuity, Diode Test, Temperature
250V AC/DC
10A Current AC or DC 10A/600V fast acting Fuse
μA/mA Current AC or DC 500mA/600V fast acting Fuse

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2-3. International Safety Symbols
This symbol adjacent to another symbol, terminal or operating device indicates that
the operator must refer to an explanation in the Operating instructions to avoid
personal injury or damage to the meter.
This symbol adjacent to one or more terminals identifies them as being associated
with ranges that may, in normal use, be subjected to particularly hazardous voltages.
For maximum safety.the meter and its test leads should not be handled when these
terminals are energized.
Double insulation
lndicates the terminal(s) so marked must not be connected to a circuit
where the 600V voltage with respect to earth ground exceeds the
maximum safety rating of the meter.
This WARNING symbol indicates a potentially hazardous situation, which
if not avoided, could result in death or serious injury.
This CAUTION symbol indicates a potentially hazardous situation, which
if not avoided, may result damage to the product.
3. Description
3-1. Meter Description
1. LCD Display
2. Non-Contact Voltage lndicator
3. MODE/RELATIVE Button
4. RANGE Button
5. MAX/MIN Button
6. HOLD/Backlight Button
7. Function Switch
8. 10A Input Jack
9. COM Input Jack
10. Positive Input Jack
11. Non-Contact Voltage Detector
12. Lanyard Hole
13. Test Lead Holders
14. Battery Cover Lock
15. Tilt Stand
16. Battery Cover

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3-2.Symbols Used on LCD Display
1. Auto Power 0ff
2. Auto Ranging
3. Maximum
4. Minimum
5. Display Hold
6. Diode Test
7. Continuity
8. Relative Mode
9. Degree Celsius/Degree Fahrenheit
10. Units of Measure List
11. Measurement Reading
12. Low Battery
13. Minus Sign
14. Direct Current
15. Alternating Current
4. Button Function
4-1. MODE and REL Button
• Press the MODE Button to select AC/DC Voltage, AC/DC Current, Frequency, Ohms, Diode
Test Continuity or Capacitance, Temperature.
• Press the REL Button for >2 second to turn on or off the Relative function .
• The Relative function zeros out the reading on the display and stores it as a reference,
subsequent readings will be displayed as the relative difference between the actual
measurement and the stored reference value.
Note: REL does not work on Frequency, Diode Test, Continuity.
4-2. RANGE Button
• When the meter is first turned on, it automatically goes into Auto Ranging.
• This automatically selects the best range for the measurements being made and is
generally the best mode for most measurements.
• For measurement situations requiring that a range be manually selected, perform the
following:
1.Press the RANGE Button, the "AUTO" display indicator will turn off.
2.Press the RANGE Button to step through the available ranges until you select the range
you want
3.Press and hold the RANGE Button for 2 seconds to exit the Manual Ranging mode and
return to Auto Ranging.
4-3. MAX/MIN Button
1.Momentarily press the MAX/MIN Button to activate the MAX/MIN mode, the "MAX“
indicator will appear on the LCD display, the meter will display and hold the maximum
reading and will update when a higher max occurs.
2.Momentarily press the MAX/MIN Button again to view the lowest reading, the "MIN"
indicator meter will appear on the LCD display, the meter will display and hold the minimum
reading and will update when a lower min” occurs.
3.Press and hold the MAX/MIN Button to end MAX/MIN and return to normal operation.
Note: The meter does not auto range when the MAX/MIN mode is active, the display will
read OL if the range is exceeded. When this occurs, exit MAX/MIN and use the RANGE
button to select a high range. MAX/MIN does not work on Frequency, Duty Cycle, Diode Test,
Continuity and Capacitance.
4-4.HOLD/Backlight Button
• Press the HOLD/Backlight Button to turn on or off the HOLD function .
• Press the HOLD/Backlight Button for >2 second to turn on or off the Backlight function.
4-5.Auto Power 0ff
• The auto off feature will turn the meter off after 15 minutes.
• To disable the auto power off feature, hold down the MODE Button and turn the meter on.
4-6.Low Battery lndication
• The " " icon will appear in the lower left corner of the display when the battery voltage
becomes low.
• Replace the battery when this appears.

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5.Operating Instructions
5-1.AC/DC Voltage (Frequency) Measurement
WARNING: Observe all safety precautions when working on live voltages.
CAUTION: Do not measure voltages if a motor on the circuit is being switched ON or 0FF.
Large voltage surges may occur that can damage the meter.
1. Set the rotatory function switch to the VAC/DC Position.
2. To select AC or DC voltage, press the MODE Button until the AC “ " or DC " " symbol
appears on the LCD display.
3. lnsert the black test lead banana plug into the negative COM lnput Jack; lnsert the red
test leadbanana plug into the Positive lnput Jack.
4. Touch the black test probe tip to the negative side of the circuit; Touch the red test probe
tip tothe positive side of the circuit.
5. Read the voltage on the LCD display.
6. Press the MODE Button to indicate “Hz“.
7. Read the frequency in the display.
5-2.Frequency (Electronic) Measurement
WARNING: Observe all safety precautions when working on live voltages.
1. Set the rotatory function switch to the Hz Position.
2. lnsert the black test lead banana plug into the negative COM lnput Jack; lnsert the red
test lead banana plug into the Positive lnput Jack.
3. Touch the test probe tips to the circuit under test.
4. Read the frequency on the display.

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5-3.AC/DC Current Measurement
WARNING: Observe all safety precautions when working on live circuits. Measurements in
the 10A range should be limited to 30 seconds maximum every 15 minutes.
1. lnsert the black test lead banana plug into the COM Input Jack.
2. For current measurements up to 10A AC/DC, set the rotary function switch to the 10A
Position and lnsert the red test lead into the 10A Input Jack.
3. For current measurements up to 400mA AC/DC, set the rotary function switch to the mA
Position and lnsert the red test lead into the Positive lnput Jack.
4. For current measurements up to 4000pA AC/DC, set the rotary function switch to the μA
Position and lnsert the red test lead into the Positive lnput Jack.
5. Press the MODE Button to select AC or DC current, the AC “ " or DC " " symbol will
be shown on the LCD display.
6. Remove power from the circuit under test, then open up the circuit at the point where you
wish to measure current.
7. Touch the black test probe tip to the neutral side of the circuit: Touch the red test probe
tip to the "hot" side of the circuit.
8. Apply power to the circuit, Read the current on the LCD display.
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5-4. Resistance Measurement
WARNING: Never test resistance on a live circuit
1. Set the rotary function switch to the Ω CAP Position.
2. Press the MODE Button until the “Ω" symbol appears on the LCD display.
3. insert the black test lead banana plug into the negative COM input Jack; lnsert the red
test lead banana plug into the Positive lnput Jack.
4. Touch the test lead probes to the component under test, if the component is installed in a
circuit, it is best to disconnect one side before testing to eliminate interference with other
devices.
5. Read the resistance in on the LCD display.

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5-5.Diode Test
WARNING: Never test diodes in a live circuit.
1. Set the rotary function switch to the Ω CAP Position.
2. Press the MODE Button until the “ " symbol appears on the LCD display.
3. lnsert the black test lead banana plug into the negative COM lnput Jack; lnsert the red
test lead banana plug into the Positive lnput Jack.
4. Touch the test lead probes to the diode under test.
5. Forward voltage will indicate 0.4 to 0.7V on the LCD display: Reverse voltage will indicate
"OL”; Shorted devices will indicate near 0 and an open device will indicate "OL" in both
polarities.
Red
Probe
Forward Test Reverse Test
Red
Probe
Black
Probe
Black
Probe
5-6.Continuity Check
WARNING: Never test continuity on a live circuit.
1. Set the rotary function switch to the Ω CAP Position.
2. Press the MODE Button until the " " symbol appears on the LCD display.
3. lnsert the black test lead banana plug into the negative COM Input Jack; lnsert the red
test lead banana plug into the Positive lnput Jack.
4. Touch the test lead probes to the device or wire under test.
5. A beeper will sound if the resistance is approx. 50 ohms or less and the resistance reading
will be shown on the LCD display.

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5-7.Capacitance Measurement
WARNING: To avoid electric shock, disconnect power to the unit under test and discharge
all capacitors before taking any capacitance measurements. Remove the batteries and unplug
the line cords.
1. Set the rotary function switch to the Ω CAP Position.
2. Press the MODE Button until the "nF” symbol appears on the LCD display.
3. lnsert the black test lead banana plug into the negative COM lnput Jack; lnsert the red
test lead banana plug into the Positive lnput Jack.
4. Touch the test leads to the capacitor to be tested, Wait until the readings settle before
ending the test.
5. Read the capacitance value in the display.
5-8.Temperature Measurement
WARNING: Do not touch the temperature probe to live circuits.
1. Set the function switch to the Temp Position.
2. Press the MODE Button to indicate oCor oF
3. Connect the temperature probe to the banana plug adapter, note the -and +markings on
the adapter.
4. Connect the adapter to the meter, making sure the - side goes into the COM lnput Jack
and the +side goes into the Positive lnput Jack.
5. Touch the tip of the temperature probe to the object being measured.
6. 6.Read the temperature on the LCD display.

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5-9. Non-Contact AC Voltage Detection
WARNING: Risk of Electrocution. Before use, always test the Voltage Detector on a known
live circuit to verify proper operation.
1. Set the rotary function switch to the NCV Position.
2. Hold the detector close to the AC voltage being tested.
3. lf no signal is detected, the LCD will show "EF", NCV indicator light doesn't flashes and
the buzzer is no sound.
4. According to the detected signal strength, LCD displays different horizontal lines.
• When the signal is strongest, LCD displays four horizontal lines, when the signal is
weakest, onlyone line.
• Meanwhile, NCV indicator light flashes, buzzer make different sound.
Note: The sensing level varies with the distance between the sensing part and the measured
ACpower cord.
Note: The detector is designed with high sensitivity. Static electricity or other sources of
energymay randomly trip the sensor. This is normal operation.
6.Maintenance and Cleaning
This Multimeter is designed to provide years of dependable service, if the following care
instructionsare performed:
1. Keep the meter dry, if it gets wet, wipe it off.
2. Use and store the meter in normal temperatures, temperature extremes can shorten the
life ofthe electronic parts and distort or melt plastic parts.
3. Handle the meter gently and carefully, dropping it can damage the electronic parts or the
case
4. Keep the meter clean, wipe the case occasionally with a damp cloth, do not use
chemicals.cleaning solvents, or detergents.
5. Use only fresh batteries of the recommended size and type, remove old or weak batteries
so theydo not leak and damage the unit.
6. lf the meter is to be stored for a long period of time, the batteries should be removed to
preventdamage to the unit.
7.Replacing The Battery
WARNING: To avoid electric shock, disconnect the test leads from any source of voltage
beforeremoving battery cover.
WARNING: To avoid electric shock, do not operate the meter until the battery cover is in
placeand securely fastened.
1. Contrarotate 180 degrees to open the back cover of battery.
2. Replace old batteries with two "AAA1.5V batteries
3. Re-assemble the meter.
8.Replacing The Fuses
WARNING: To avoid electric shock, disconnect the test leads from any source of voltage
beforeremoving the fuse door.
WARNING: To avoid electric shock, do not operate your meter until the fuse cover is in place
andfastened securely.
1. Disconnect the test leads from the meter.
2. Contrarotate 180 degrees to open the back cover of battery for the 500mA/600V fast
and Removethe rear cover for the 10A/600V fast .
3. Gently remove the old fuse and install the new fuse into the holder.
4. Always use a fuse of the proper size and value (500mA/600V fast blow for the pA/mA
range or10A/600V fast blow for the 10A range).
5. Replace and secure the rear cover.

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9. Specications
Function Range Accuracy
DC Voltage
400.0mV 0.1mV
±(0.5%+8 digits)
4.000mV 0.001V
40.00V 0.01V
400.0V 0.1V
600V 1V
AC True RMS
Voltage
4.000V 0.001V ±(1.2%+3 digits)
40.00V 0.01V
±(1.2%+5 digits)400.0V 0.1V
600V 0.1V
All AC voltage ranges are specified from 5% of range to 100% of range.
AC Voltage Bandwidth: 50Hz to 60Hz (All wave); 50Hz to 1kHz (Sine wave)
DC Current
400.0μA 0.1μA
±(1.0%+5 digits)4000μA 1μA
40.00mA 0.01mA
400.0mA 0.1mA ±(1.2%+8 digits)
4.000A 0.001A ±(2.0%+3 digits)
10.00A 0.01A ±(2.0%+5 digits)
AC True RMS
Current
400.0μA 0.1μA
±(1.0%+5 digits)4000μA 1μA
40.00mA 0.01mA
400.0mA 0.1mA ±(1.2%+8 digits)
4.000A 0.001A ±(2.0%+3 digits)
10.00A 0.01A ±(2.0%+5 digits)
All AC voltage ranges are specified from 5% of range to 100% of range.
AC Voltage Bandwidth: 50Hz to 60Hz (All wave); 50Hz to 400Hz (Sine wave)
Temperature -18 to 1000oC 1oC ±(1.5%+5 oC)
0 to 1832oF 1oF ±(1.5%+9 oF)
Function Range Resolution Accuracy
Resistance
400.0Ω 0.1Ω
±(1.2% + 5 digits)
4.000kΩ 0.001kΩ
40.00kΩ 0.01kΩ
400.0kΩ 0.1kΩ
4.000MΩ 0.001MΩ ±(2.5% + 8 digits)
40.00MΩ 0.01MΩ ±(3.0% + 8 digits)
Capacitance
4.000nF 0.001nF ±(3.5% + 60 digits)
40.00nF 0.01nF ±(3.5% + 10 digits)
400.0nF 0.1nF
4.000μF 0.001μF ±(4.0% + 5 digits)
40.00μF 0.01μF
400.0μF 0.1μF ±(3.5% + 5 digits)
4.000mF 0.001mF
Frequency
(Electrical)
4.000Hz 0.001Hz
±(1.2% +5 digits)
40.00Hz 0.01Hz
400.0Hz 0.1Hz
4.000kHz 0.001KHz
10.00kHz 0.01KHz
Sensitivity: >1.5V RMS
Frequency
(Electronic)
2.000Hz~4.000Hz 0.001Hz
±(1.2% + 5 digits)
40.00Hz 0.01Hz
400.0Hz 0.1Hz
4.000kHz 0.001KHz
40.00kHz 0.01kHz
400.0kHz 0.1kHz
4.000MHz 0.001MHz
10.00kHz 0.01KHz
>0.8V RMS while ≤100kHz; 3V RMS while >100kHz
Note: Accuracy is stated at 18 to 28°C (65 to 83°F) and less than 75%RH.
Note: Accuracy specifications consist of two elements:
• (% reading)-This is the accuracy of the measurement circuit.
• (+ digits]-This is the accuracy of the analog to digital converter.