Sealey TA320 User manual

User's Guide
True RMS Industrial Multimeter

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Introduction
This meter measures AC/DC Voltage, AC/DC Current, Resistance,
Capacitance, Frequency (electrical & electronic), Duty Cycle, Diode
Test,Insulation Test, and Continuity plus Thermocouple Temperature.
It can store and recall data. It features a waterproof, rugged design for
heavy duty use. Proper use and care of this meter will provide many
years of reliable service.
Safety
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 WARNING symbol indicates a potentially
hazardous situation, which if not avoided, could
result in death or serious injury.
This CAUTION symbol indicates a potentially haza
rdous situation, which if not avoided, may result da
mage to the product.
This symbol advises the user that the terminal(s)
so marked must not be connected to a circuit point
at which the voltage with respect to earth ground
exceeds (in this case) 1000 VAC or VDC.
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.
This symbol indicates that a device is protected
throughout by double insulation or reinforced
insulation.
WARNING
CAUTION
MAX
1000V

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PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY I
Equipment of OVERVOLTAGE CATEGORY I is equipment for
connection to circuits in which measures are taken to limit the
transient overvoltages to an appropriate low level.
Note – Examples include protected electronic circuits.
OVERVOLTAGE CATEGORY II
Equipment of OVERVOLTAGE CATEGORY II is energy-consuming
equipment to be supplied from the fixed installation.
Note – Examples include household, office, and laboratory appliances.
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

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SAFETY INSTRUCTIONS
This meter has been designed for safe use, but must be operated with
caution. The rules listed below must be carefully followed for safe
operation.
1. NEVER apply voltage or current to the meter that exceeds the
specified maximum:
Input Protection Limits
Function
Maximum Input
V DC or V AC
1000VDC/AC rms
mA AC/DC
500mA 1000V fast acting fuse
A AC/DC
10A 1000V fast acting fuse (20A
for 30 seconds max every 15
minutes)
Frequency, Resistance,
Capacitance, Duty Cycle,
Diode Test, Continuity
1000VDC/AC rms
Temperature
1000VDC/AC rms
Surge Protection: 8kV peak per IEC 61010
2. USE EXTREME CAUTION when working with high voltages.
3. DO NOT measure voltage if the voltage on the "COM" input jack
exceeds 1000V above earth ground.
4. NEVER connect the meter leads across a voltage source while
the function switch is in the current, resistance, or diode mode.
Doing so can damage the meter.
5. ALWAYS discharge filter capacitors in power supplies and
disconnect the power when making resistance or diode tests.

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6. ALWAYS turn off the power and disconnect the test leads before
opening the covers to replace the fuse or batteries.
7. NEVER operate the meter unless the back cover and the battery
and fuse covers are in place and fastened securely.
If the equipment is used in a manner not specified by the
manufacturer, the protection provided by the equipment may be
impaired.
Controls and Jacks
1. 40,000 count LCD display
2. MAX/MIN (-)button
3. STORE(<RECALL) button
4. RANGE(SETUP) button
5. INSULATION TEST button
6. MODE button
7. Function switch
8. mA, µA and 10A input jacks
9. REL(+) button
10. HOLD(PEAKHOLD>) button
11. EXIT(AC+DC) button
12. Backlight button
13. Positive input jack
14. COM input jack
Note: Tilt stand and battery compartment are on rear of unit.
Ω
10A
mA
A
1
2
3
4
5
6
7
8
9
10
11
12
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Symbols and Annunciators
•))) Continuity
Diode test
Battery status
n nano (10-9) (capacitance)
µmicro (10-6) (amps, cap)
m milli (10-3) (volts, amps)
A Amps
k kilo (103) (ohms)
F Farads (capacitance)
M mega (106) (ohms)
ΩOhms PEAK Peak Hold
Hz Hertz (frequency) V Volts
% Percent (duty ratio) REL Relative
AC Alternating current AUTO Autoranging
DC Direct current HOLD Display hold
ºF Degrees Fahrenheit ºC Degrees Centigrade
MAX Maximum MIN Minimum
N0. Serial number
S second
left auxiliary display
right auxiliary display
SET Set up parameter
AC +DC Alternating current + Direct current
TRMS Ture RMS
STO Store
RCL Recall
AUTO Auto Range
Timing symbol
Backlight
bargraph

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Operating Instructions
WARNING: Risk of electrocution. High-voltage circuits, both AC and
DC, are very dangerous and should be measured with great care.
1. ALWAYS turn the function switch to the OFF position when the
meter is not in use.
2. If “OL” appears in the display during a measurement, the value
exceeds the range you have selected. Change to a higher range.
DC VOLTAGE MEASUREMENTS
CAUTION: Do not measure DC voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green VDC
position.
2. Insert the black test lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive Vjack.
3. Touch the black test probe tip to the negative
side of the circuit.
Touch the red test probe tip to the positive
side of the circuit.
4. Read the voltage in the display.

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AC VOLTAGE (FREQUENCY, DUTY CYCLE) MEASUREMENTS
WARNING: Risk of Electrocution. The probe tips may not be long
enough to contact the live parts inside some 240V outlets for
appliances because the contacts are recessed deep in the outlets.
As a result, the reading may show 0 volts when the outlet actually
has voltage on it. Make sure the probe tips are touching the metal
contacts inside the outlet before assuming that no voltage is
present.
CAUTION: Do not measure AC voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green
VAC/Hz/% position.
2. Insert the black test lead banana plug
into the negative COM jack.
Insert red test lead banana plug into the
positive Vjack.
3. 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.
4. Read the voltage in the main display and
the frequency in the right auxiliary display
5. Press and hold the MODE button 2
second to indicate “Hz”.
6. Read the frequency in the main display.
7. Press the MODE button to indicate “%”.
8. Read the % of duty cycle in the main display.
9. Press EXIT for 2 seconds into the function of AC+DC. Test DC
and AC TURE Rms.

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MV VOLTAGE MEASUREMENTS
CAUTION: Do not measure mV voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green mV position.
2. Press the MODE button to indicate “DC”.or
““AC ”, or in AC range press EXIT for two
seconds and chose ”AC+DC”
3. Insert the black test lead banana plug into
the
negative COM jack.
Insert the red test lead banana plug into the
positive Vjack.
4. Touch the black test probe tip to the
negative side of the circuit.
Touch the red test probe tip to the positive
side of the circuit.
5. Read the mV voltage in the display.

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DC CURRENT MEASUREMENTS
CAUTION: Do not make 20A current measurements 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 banana plug into
the negative COM jack.
2. For current measurements up to 4000µA DC,
set the function switch to the yellow µA
position and insert the red test lead banana
plug into the µA/mA jack.
3. For current measurements up to 400mA DC,
set the function switch to the yellow mA
position and insert the red test lead banana
plug into the µA/mA jack.
4. For current measurements up to 20A DC,
set the function switch to the yellow
10A/HZ/% position and insert the red test
lead banana plug into the 10A jack.
5. Press the MODE button to indicate “DC” on
the 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 negative side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
8. Apply power to the circuit.
9. Read the current in the display.

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AC CURRENT (FREQUENCY, DUTY CYCLE) MEASUREMENTS
CAUTION: Do not make 20A current measurements 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 banana plug
into the negative COM jack.
2. For current measurements up to
4000µA AC, set the function switch to
the yellow µAposition and insert the
red test lead banana plug into the
µA/mA jack.
3. For current measurements up to
400mA AC, set the function switch to
the yellow mA position and insert the
red test lead banana plug into the
µA/mA jack.
4. For current measurements up to 20A
AC, set the function switch to the yellow
10A/HZ/% position and insert the red
test lead banana plug into the 10A jack.
5. Press the MODE button to indicate
“AC” on the 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.
9. Read the current in the display. In the 10AAC range, right
auxiliary display frequency.
10. Press and hold the MODE button to indicate “Hz”.
11. Read the frequency in the display.
12. Momentarily press the MODE button again to indicate “%”.
13. Read the % duty cycle in the display.

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14. Press and hold the MODE button to return to current
measurement.
15. Press EXIT for 2 seconds into the function of AC+DC. Test DC
and AC TURE Rms.
RESISTANCE MEASUREMENTS
WARNING: To avoid electric shock, disconnect power to the unit
under test and discharge all capacitors before taking any
resistance measurements. Remove the batteries and unplug the
line cords.
1. Set the function switch to the green
ΩCAP position.
2. Insert the black test lead banana plug
into the negative COM jack.
Insert the red test lead banana plug into
the positive Ωjack.
3. Press the MODE button to indicate
“Ω”on the display.
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. Read the resistance in the display.

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CONTINUITY CHECK
WARNING: To avoid electric shock, never measure continuity on
circuits or wires that have voltage on them.
1. Set the function switch to the green
ΩCAP position.
2. Insert the black lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive Ωjack.
3. Press the MODE button to indicate“ " and
“Ω”on the display
4. Touch the test probe tips to the circuit or wire
you wish to check.
5. If the resistance is less than approximately
35Ω, the audible signal will sound. If the
circuit is open, the display will indicate “OL”.
DIODE TEST
1. Set the function switch to the green ΩCAP
position.
2. Insert the black test lead banana plug into the
negative COM jack and the red test lead
banana plug into the positive Vjack.
3. Press the MODE button to indicate“ “ and
“V” on the display.
4. Touch the test probes to the diode under test.
Forward voltage will typically indicate 0.400 to
0.700V. Reverse voltage will indicate “OL”.
Shorted devices will indicate near 0V and an
open device will indicate “OL” in both
polarities.

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CAPACITANCE MEASUREMENTS
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 green
ΩCAP position.
2. Insert the black test lead banana plug into
the negative COM jack.
3. Insert the red test lead banana plug into the
positive Vjack.
4. Press the MODE button to indicate “F”
5. Touch the test leads to the capacitor to be
tested.
Read the capacitance value in the
Display
TEMPERATURE MEASUREMENTS
1. Set the function switch to the green
Temp position.
2. Insert the Temperature Probe into the
input jacks, making sure to observe the
correct polarity.
3. Press the MODE button to indicate “ºF”
or “ºC”
4. Touch the Temperature Probe head to
the part whose temperature you wish to
measure. Keep the probe touching the
part under test until the reading
stabilizes (about 30 seconds).
5. Read the temperature in the display.
Note: The temperature probe is fitted with a type K mini connector.
A mini connector to banana connector adaptor is supplied for
connection to the input banana jacks.

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FREQUENCY (DUTY CYCLE) MEASUREMENTS (ELECTRONIC)
1. Set the rotary function switch to the green Hz/% position.
2. Insert the black lead banana plug into the
negative COM jack and the red test lead
banana
plug into the positive Hz jack.
3. Touch the test probe tips to the circuit under
test.
4. Read the frequency on the display.
5. Press the MODE button to indicate “%”.
6. Read the % duty cycle in the display.
% 4 – 20mA MEASUREMENTS
1. Set up and connect as described for DC mA measurements.
2. Set the rotary function switch to the 4-20mA% position.
3. The meter will display loop current as a % with 0mA=-25%,
4mA=0%, 20mA=100%, and 24mA=125%.
INSULATION RESISTANCE MEASUREMENTS
a) Set the rotary function switch to the INSULATION position ,
and Press the RANGE button to chose one of the voltage which
display on the top left corner.
b)Connect two testing lines to the tested；
c)Push down and hold the “TEST” button /or press the “ LOCK”
keystoke first and then the “TEST” button, if the tested is
electriferous and its voltage ( AC/DC) is over 30V, it will refuse work
and no high-voltage testing occurs, simultaneity, it shows “>30V” on
the LCD, the symbol “ ” flashes, and the buzzer warns frequently.
if the tested is diselectriferous or its voltage is lower than 30V, it will
enter into the formal testing process and brings the high-voltage. on
the primary display, the insulation resistance in MΩis indicated in-

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phase with analog bar; on the top right corner display, the tested
insulation voltage in V (DC) is indicated, the symbol “ ” flashes
and the buzzer warns frequently
d)Being free from the “TEST” button or pushing down the “TEST”
button in the “LOCK “ status can exit from the “LOCK” status and
shutoff the high-voltage，synchronously, the resistance values is
indicated in the primary display will be held, and the top right corner
display still be in the status of monitoring the insulation voltage for
the tested .
e)Subsequently, discharge the balance insulation voltage of the tested
through the inner switch of the meter.
Turning the function switch or press the EXIT button
can exit automatically from testing status during the process。
POWER TOOLS AND AMALL APPLIANCES
This test would also apply to other similar equipment that has a line
cord. For double insulated power tools, the megohmmeter lead shown
connected to the housing would be connected to some metal part lf
the tool(e..g chuck,blade).
Note:The switch of the device must be in the “ON”position and the
main power should be disconnected.
MOTORS
AC-Disconnect the motor from the line by disconnecting the wires at
the motor terminals or by opening the main switch. If the main switch
is used and the motor also has a starter then the starter must be held,
by some means, in the “ON” position. In the latter case, the measured
resistance will include the resistance of the motor, wire and all other
components between the motor and the main switch. If a weakness is
in dicated, the motor and other components should be checked

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individually. If the motor is disconnected at the motor terminals,
connect one megohmmeter lead to the grounded motor housing and
the other lead to One of the motor leads. DC-Disconnect the motor
from the line. To test the brush rigging,field coils and armature
connect one megohmmeter lead to the grounded motor housing and
the other lead to the brush on the commutator. If the resistance
measurement indicates a weakness,raise the brushes off the
commutator and separately test the armature, field coils and brush
rigging by connecting one megohmmeter lead to each of them
individually, leaving the other connected to the grounded motor
housing. The above also applies to DC Gemerators.

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CABLES
Disconnect the cable from the line. Also disconnect opposite end to
avoid errors due to leakage from other equipment. Check each
conductor to ground and /or lead sheath by connecting one
megohmmeter lead to a ground and /or lead sheather and the other
megohmmeter lead to each of the conductors in turn. Check insulation
resistance between conductors by connecting megohmmeter leads to
conductors in pairs.

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AUTORANGING/MANUAL RANGE SELECTION
When the meter is first turned on, it automatically goes into
AutoRanging. 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 key. The “AUTO” display indicator will turn off.
2. Press the RANGE key to step through the available ranges until
you select the range you want.
3. To exit the Manual Ranging mode and return to Autoranging,
press EXIT
Note:Manual ranging does not apply for the Temperature functions.
MAX/MIN
1. Press the MAX/MIN key to activate the MAX/MIN recording mode.
The display icon "MAX" will appear. The meterleft auxiliary
displaywill display and hold the maximum reading and will update
only when a new “max” occurs.The display icon "MIN" will appear.
The right auxiliary displaymeter will display and hold the minimum
reading and will update only when a new “min” occurs.
2.To exit MAX/MIN mode press EXIT
RELATIVE MODE
The relative measurement feature allows you to make
measurements relative to a stored reference value. A reference
voltage, current, etc. can be stored and measurements made in
comparison to that value. The displayed value is the difference
between the reference value and the measured value. Note:
Relative mode does not operate in the 4-20mA function.
1. Perform the measurement as described in the operating
instructions.
2. Press the REL button to store the reading in the display and the
"REL" indicator will appear on the display.