Hioki 3280-10F User manual

AC CLAMP METER
Instruction Manual
Nov. 2015 Edition 1
Printed in Japan
3280H961-00 15-11H
3280-10F
3280-20F
EN
Device may be connected to or disconnected from a live conductor
Flexible sensors can be connected to or disconnected from
live conductors when using appropriate protective insulation.
Other sensors can only be connected to or disconnected from
insulated conductors suited to the voltage of the conductor
under measurement.
Grounding
terminal DC (direct current) AC (alternating current)
Measurement categories
This instrument’s current measurement part conforms to the safety
requirements for CAT III 600 Vand the voltage measurement part
conforms to the safety requirements for CAT II 600 VCAT III 300 V
measuring instruments.
Service entrance
Distribution panel
Service drop Internal wiring
Power meter
Fixed Installation
Outlet
CAT IV CAT III CAT II
DANGER
Measuring a location with a higher category number
than the measurement category indicated on this
device may result in a serious accident such as
electric shock.
To avoid electric shockdo not touch the portion
beyond the protective barrier during use.
Never apply voltage to the test leads when the
resistance and continuity functions are selected.
Doing so may damage the instrument and result in
bodily injury. To avoid electrical accidentsremove
power from the circuit before measuring.
WARNING
•To avoid electric shockshort circuits and damage
to the instrumentdisconnect the test leads from the
measurement object before switching the rotary switch.
•To prevent electric shockwhen measuring the voltage
of a power line use a test lead that satisfies the
following criteria:
• Conforms to safety standards IEC61010 or EN61010
• Of measurement category III or IV
• Its rated voltage is higher than the voltage to be measured
• The optional test leads for this instrument conform to the
safety standard EN61010. Use a test lead in accordance
with its defined measurement category and rated voltage.
• Installing the instrument in inappropriate locations may
cause a malfunction of instrument or may give rise to
an accident. Avoid the following locations:
•Exposed to direct sunlight or high temperature
•Exposed to corrosive or combustible gases
•Exposed to a strong electromagnetic field or
electrostatic charge
• Near induction heating systems (such as high-frequency
induction heating systems and IH cooking equipment)
• Susceptible to vibration
•Exposed to wateroilchemicalsor solvents
•Exposed to high humidity or condensation
•Exposed to high quantities of dust particles
WARNING
•Since there is a risk of electric shockcheck that the
insulation on the test lead and flexible sensor (optional) are
neither ripped nor tornand no metal conductor inside the
wire are exposed before using the instrument. If damaged
replace them with those specified by our company.
• To prevent a short circuit accidentbe sure to use the
test leads with the sleeves attached when performing
measurements in the CAT III measurement category.
• If the sleeves are inadvertently removed during
measurementstop the measurement.
• With regard to the electricity supplythere are risks of
electric shockheat generationfireand arc flash due
to short circuits. If persons unfamiliar with electricity
measuring instrument are to use the instrumentanother
person familiar with such instruments must supervise
operations.
•This instrument is measured on a live line. To prevent
electric shockuse appropriate protective insulation and
adhere to applicable laws and regulations.
•Handle and dispose of batteries in accordance with
local regulations.
CAUTION
Do not place foreign objects between the jaw tips (or
flexible loop couplings) or insert foreign objects into the
gaps of the jaws (or flexible loop couplings). Doing so
may worsen the performances of the sensor or interfere
with clamping action.
Poor performance or damage from battery leakage
could result. Observe the cautions listed below:
• Do not use batteries after their recommended expiry date.
• Do not allow weak batteries to remain in the instrument.
• Replace batteries only with the specified type.
• Remove the batteries from the instrument if it is to be
stored for a long time.
•The indicator lights up when the remaining battery
capacity is low. In this casethe instrument's reliability is
not guaranteed. Replace the battery immediately.
•To avoid battery depletionturn the rotary switch OFF
after use (the auto power save feature consumes a small
amount of current).
Inspection Before Measurement
•Verify that the instrument operates normally to ensure that no
damage occurred during storage or shipping. If you find any
damagecontact your authorized Hioki distributor or reseller.
•If damage is suspectedcheck the section below before contacting
your authorized Hioki distributor or reseller.
(1) Check that the test lead is not broken.
Replace with the specified L9208 Test Lead.
(2) Check that the resistance measurement and continuity test
operates normally.
Have the instrument repaired by the your authorized Hioki distributor
or reseller. The instrument may have been subject to a voltage of
greater than 600 V during resistance measurement or continuity
testing.
(3) Check that the battery voltage is not low.
Replace the batteries.
Maintenance/Inspection
Cleaning
• Measurements are degraded by dirt on the mating surfaces of the
jaw (or flexible loop coupling)so keep the surfaces clean by gently
wiping with a softdry cloth.
•To clean the devicewipe it gently with a soft cloth moistened with
water or mild detergent.
•Wipe the LCD display gently with a softdry cloth.
Insert/Replace Batteries
Necessary tool: Phillips screwdriver and CR2032 Coin-shaped lithium battery
NO
OK
12
34
Do not turn the adjustment screw inside the battery case. Doing
so will cause the instrument to report abnormal measured values.
Functions
Display will automatically turn off if the instrument is not used
for 30 min. (Auto power-saving function)
To resume instrument operation in the previous stateselect the
“OFF” position with the rotary switch and then move the switch to
the desired function.
To cancel auto power-saving function
1. Select the desired function with the rotary switch while holding
down key.
2. The LCD display will change from [APS] to [OFF]and the auto
power-saving function will be disabled.
3. Setting the rotary switch to “OFF” and then reselecting the
desired function will enable the auto power-saving function.
Automatically sets the measurement range to the most appropriate
range (Auto-range function)
Displays [AUTO]
To set the measurement range arbitrarily (Manual-range function)
1. Select the desired function with the rotary switch while holding
down key.
2. Press key to switch the range.
(Can set the range as desiredexcept during continuity testing.)
Indication when input exceeds the measurement range (Overflow indication)
Displays [OF] or [-OF]
Parts Names
RearFront
Jaw
Barrier
Operation grip
LCD Display
Rotary switch
key
HOLD key
(Press to hold the
display value.)
y
ch
Test lead or flexible sensors plug
Example: 3280-10F
Measurement
terminal Battery cover
Warranty
Warranty malfunctions occurring under conditions of normal use in
conformity with the Instruction Manual and Product Precautionary
Markings will be repaired free of charge. This warranty is valid for a
period of three (3) years from the date of purchase. Please contact
the distributor from which you purchased the product for further
information on warranty provisions.
Introduction
Thank you for purchasing the Hioki 3280-10F3280-20F AC Clamp
Meter. To obtain maximum performance from the instrumentplease
read this manual firstand keep it handy for future reference.
3280-10F Average value measurement RMS conversion model
3280-20F True RMS measurement model
Safety Notes
This instrument is designed to conform to IEC 61010 Safety
Standardsand has been thoroughly tested for safety prior to
shipment. Howeverusing the instrument in a way not described in
this manual may negate the provided safety features. Before using
the instrumentbe certain to carefully read the following safety notes.
Notation
In this documentthe risk seriousness and the hazard levels are
classified as follows.
DANGER Imminent risk of operator death or serious injury
WARNING Potential for operator death or serious injury
CAUTION Potential for minor operator injury or device
damage or malfunction
Risk of electric shock
Prohibited actions
Actions that must be performed
Symbols affixed to the device
Precaution or hazard (See corresponding topic.)
Risk of electric shock
Protected throughout by double insulation or reinforced insulation

AC CLAMP METER
Instruction Manual
Nov. 2015 Edition 1
Printed in Japan
3280H961-00 15-11H
3280-10F
3280-20F
EN
Device may be connected to or disconnected from a live conductor
Flexible sensors can be connected to or disconnected from
live conductors when using appropriate protective insulation.
Other sensors can only be connected to or disconnected from
insulated conductors suited to the voltage of the conductor
under measurement.
Grounding
terminal DC (direct current) AC (alternating current)
Measurement categories
This instrument’s current measurement part conforms to the safety
requirements for CAT III 600 Vand the voltage measurement part
conforms to the safety requirements for CAT II 600 VCAT III 300 V
measuring instruments.
Service entrance
Distribution panel
Service drop Internal wiring
Power meter
Fixed Installation
Outlet
CAT IV CAT III CAT II
DANGER
Measuring a location with a higher category number
than the measurement category indicated on this
device may result in a serious accident such as
electric shock.
To avoid electric shockdo not touch the portion
beyond the protective barrier during use.
Never apply voltage to the test leads when the
resistance and continuity functions are selected.
Doing so may damage the instrument and result in
bodily injury. To avoid electrical accidentsremove
power from the circuit before measuring.
WARNING
•To avoid electric shockshort circuits and damage
to the instrumentdisconnect the test leads from the
measurement object before switching the rotary switch.
•To prevent electric shockwhen measuring the voltage
of a power line use a test lead that satisfies the
following criteria:
• Conforms to safety standards IEC61010 or EN61010
• Of measurement category III or IV
• Its rated voltage is higher than the voltage to be measured
• The optional test leads for this instrument conform to the
safety standard EN61010. Use a test lead in accordance
with its defined measurement category and rated voltage.
• Installing the instrument in inappropriate locations may
cause a malfunction of instrument or may give rise to
an accident. Avoid the following locations:
•Exposed to direct sunlight or high temperature
•Exposed to corrosive or combustible gases
•Exposed to a strong electromagnetic field or
electrostatic charge
• Near induction heating systems (such as high-frequency
induction heating systems and IH cooking equipment)
• Susceptible to vibration
•Exposed to wateroilchemicalsor solvents
•Exposed to high humidity or condensation
•Exposed to high quantities of dust particles
WARNING
•Since there is a risk of electric shockcheck that the
insulation on the test lead and flexible sensor (optional) are
neither ripped nor tornand no metal conductor inside the
wire are exposed before using the instrument. If damaged
replace them with those specified by our company.
• To prevent a short circuit accidentbe sure to use the
test leads with the sleeves attached when performing
measurements in the CAT III measurement category.
• If the sleeves are inadvertently removed during
measurementstop the measurement.
• With regard to the electricity supplythere are risks of
electric shockheat generationfireand arc flash due
to short circuits. If persons unfamiliar with electricity
measuring instrument are to use the instrumentanother
person familiar with such instruments must supervise
operations.
•This instrument is measured on a live line. To prevent
electric shockuse appropriate protective insulation and
adhere to applicable laws and regulations.
•Handle and dispose of batteries in accordance with
local regulations.
CAUTION
Do not place foreign objects between the jaw tips (or
flexible loop couplings) or insert foreign objects into the
gaps of the jaws (or flexible loop couplings). Doing so
may worsen the performances of the sensor or interfere
with clamping action.
Poor performance or damage from battery leakage
could result. Observe the cautions listed below:
• Do not use batteries after their recommended expiry date.
• Do not allow weak batteries to remain in the instrument.
• Replace batteries only with the specified type.
• Remove the batteries from the instrument if it is to be
stored for a long time.
•The indicator lights up when the remaining battery
capacity is low. In this casethe instrument's reliability is
not guaranteed. Replace the battery immediately.
•To avoid battery depletionturn the rotary switch OFF
after use (the auto power save feature consumes a small
amount of current).
Inspection Before Measurement
•Verify that the instrument operates normally to ensure that no
damage occurred during storage or shipping. If you find any
damagecontact your authorized Hioki distributor or reseller.
•If damage is suspectedcheck the section below before contacting
your authorized Hioki distributor or reseller.
(1) Check that the test lead is not broken.
Replace with the specified L9208 Test Lead.
(2) Check that the resistance measurement and continuity test
operates normally.
Have the instrument repaired by the your authorized Hioki distributor
or reseller. The instrument may have been subject to a voltage of
greater than 600 V during resistance measurement or continuity
testing.
(3) Check that the battery voltage is not low.
Replace the batteries.
Maintenance/Inspection
Cleaning
• Measurements are degraded by dirt on the mating surfaces of the
jaw (or flexible loop coupling)so keep the surfaces clean by gently
wiping with a softdry cloth.
•To clean the devicewipe it gently with a soft cloth moistened with
water or mild detergent.
•Wipe the LCD display gently with a softdry cloth.
Insert/Replace Batteries
Necessary tool: Phillips screwdriver and CR2032 Coin-shaped lithium battery
NO
OK
12
34
Do not turn the adjustment screw inside the battery case. Doing
so will cause the instrument to report abnormal measured values.
Functions
Display will automatically turn off if the instrument is not used
for 30 min. (Auto power-saving function)
To resume instrument operation in the previous stateselect the
“OFF” position with the rotary switch and then move the switch to
the desired function.
To cancel auto power-saving function
1. Select the desired function with the rotary switch while holding
down key.
2. The LCD display will change from [APS] to [OFF]and the auto
power-saving function will be disabled.
3. Setting the rotary switch to “OFF” and then reselecting the
desired function will enable the auto power-saving function.
Automatically sets the measurement range to the most appropriate
range (Auto-range function)
Displays [AUTO]
To set the measurement range arbitrarily (Manual-range function)
1. Select the desired function with the rotary switch while holding
down key.
2. Press key to switch the range.
(Can set the range as desiredexcept during continuity testing.)
Indication when input exceeds the measurement range (Overflow indication)
Displays [OF] or [-OF]
Parts Names
RearFront
Jaw
Barrier
Operation grip
LCD Display
Rotary switch
key
HOLD key
(Press to hold the
display value.)
y
ch
Test lead or flexible sensors plug
Example: 3280-10F
Measurement
terminal Battery cover
Warranty
Warranty malfunctions occurring under conditions of normal use in
conformity with the Instruction Manual and Product Precautionary
Markings will be repaired free of charge. This warranty is valid for a
period of three (3) years from the date of purchase. Please contact
the distributor from which you purchased the product for further
information on warranty provisions.
Introduction
Thank you for purchasing the Hioki 3280-10F3280-20F AC Clamp
Meter. To obtain maximum performance from the instrumentplease
read this manual firstand keep it handy for future reference.
3280-10F Average value measurement RMS conversion model
3280-20F True RMS measurement model
Safety Notes
This instrument is designed to conform to IEC 61010 Safety
Standardsand has been thoroughly tested for safety prior to
shipment. Howeverusing the instrument in a way not described in
this manual may negate the provided safety features. Before using
the instrumentbe certain to carefully read the following safety notes.
Notation
In this documentthe risk seriousness and the hazard levels are
classified as follows.
DANGER Imminent risk of operator death or serious injury
WARNING Potential for operator death or serious injury
CAUTION Potential for minor operator injury or device
damage or malfunction
Risk of electric shock
Prohibited actions
Actions that must be performed
Symbols affixed to the device
Precaution or hazard (See corresponding topic.)
Risk of electric shock
Protected throughout by double insulation or reinforced insulation

AC CLAMP METER
Instruction Manual
Nov. 2015 Edition 1
Printed in Japan
3280H961-00 15-11H
3280-10F
3280-20F
EN
Device may be connected to or disconnected from a live conductor
Flexible sensors can be connected to or disconnected from
live conductors when using appropriate protective insulation.
Other sensors can only be connected to or disconnected from
insulated conductors suited to the voltage of the conductor
under measurement.
Grounding
terminal DC (direct current) AC (alternating current)
Measurement categories
This instrument’s current measurement part conforms to the safety
requirements for CAT III 600 Vand the voltage measurement part
conforms to the safety requirements for CAT II 600 VCAT III 300 V
measuring instruments.
Service entrance
Distribution panel
Service drop Internal wiring
Power meter
Fixed Installation
Outlet
CAT IV CAT III CAT II
DANGER
Measuring a location with a higher category number
than the measurement category indicated on this
device may result in a serious accident such as
electric shock.
To avoid electric shockdo not touch the portion
beyond the protective barrier during use.
Never apply voltage to the test leads when the
resistance and continuity functions are selected.
Doing so may damage the instrument and result in
bodily injury. To avoid electrical accidentsremove
power from the circuit before measuring.
WARNING
•To avoid electric shockshort circuits and damage
to the instrumentdisconnect the test leads from the
measurement object before switching the rotary switch.
•To prevent electric shockwhen measuring the voltage
of a power line use a test lead that satisfies the
following criteria:
• Conforms to safety standards IEC61010 or EN61010
• Of measurement category III or IV
• Its rated voltage is higher than the voltage to be measured
• The optional test leads for this instrument conform to the
safety standard EN61010. Use a test lead in accordance
with its defined measurement category and rated voltage.
• Installing the instrument in inappropriate locations may
cause a malfunction of instrument or may give rise to
an accident. Avoid the following locations:
•Exposed to direct sunlight or high temperature
•Exposed to corrosive or combustible gases
•Exposed to a strong electromagnetic field or
electrostatic charge
• Near induction heating systems (such as high-frequency
induction heating systems and IH cooking equipment)
• Susceptible to vibration
•Exposed to wateroilchemicalsor solvents
•Exposed to high humidity or condensation
•Exposed to high quantities of dust particles
WARNING
•Since there is a risk of electric shockcheck that the
insulation on the test lead and flexible sensor (optional) are
neither ripped nor tornand no metal conductor inside the
wire are exposed before using the instrument. If damaged
replace them with those specified by our company.
• To prevent a short circuit accidentbe sure to use the
test leads with the sleeves attached when performing
measurements in the CAT III measurement category.
• If the sleeves are inadvertently removed during
measurementstop the measurement.
• With regard to the electricity supplythere are risks of
electric shockheat generationfireand arc flash due
to short circuits. If persons unfamiliar with electricity
measuring instrument are to use the instrumentanother
person familiar with such instruments must supervise
operations.
•This instrument is measured on a live line. To prevent
electric shockuse appropriate protective insulation and
adhere to applicable laws and regulations.
•Handle and dispose of batteries in accordance with
local regulations.
CAUTION
Do not place foreign objects between the jaw tips (or
flexible loop couplings) or insert foreign objects into the
gaps of the jaws (or flexible loop couplings). Doing so
may worsen the performances of the sensor or interfere
with clamping action.
Poor performance or damage from battery leakage
could result. Observe the cautions listed below:
• Do not use batteries after their recommended expiry date.
• Do not allow weak batteries to remain in the instrument.
• Replace batteries only with the specified type.
• Remove the batteries from the instrument if it is to be
stored for a long time.
•The indicator lights up when the remaining battery
capacity is low. In this casethe instrument's reliability is
not guaranteed. Replace the battery immediately.
•To avoid battery depletionturn the rotary switch OFF
after use (the auto power save feature consumes a small
amount of current).
Inspection Before Measurement
•Verify that the instrument operates normally to ensure that no
damage occurred during storage or shipping. If you find any
damagecontact your authorized Hioki distributor or reseller.
•If damage is suspectedcheck the section below before contacting
your authorized Hioki distributor or reseller.
(1) Check that the test lead is not broken.
Replace with the specified L9208 Test Lead.
(2) Check that the resistance measurement and continuity test
operates normally.
Have the instrument repaired by the your authorized Hioki distributor
or reseller. The instrument may have been subject to a voltage of
greater than 600 V during resistance measurement or continuity
testing.
(3) Check that the battery voltage is not low.
Replace the batteries.
Maintenance/Inspection
Cleaning
• Measurements are degraded by dirt on the mating surfaces of the
jaw (or flexible loop coupling)so keep the surfaces clean by gently
wiping with a softdry cloth.
•To clean the devicewipe it gently with a soft cloth moistened with
water or mild detergent.
•Wipe the LCD display gently with a softdry cloth.
Insert/Replace Batteries
Necessary tool: Phillips screwdriver and CR2032 Coin-shaped lithium battery
NO
OK
12
34
Do not turn the adjustment screw inside the battery case. Doing
so will cause the instrument to report abnormal measured values.
Functions
Display will automatically turn off if the instrument is not used
for 30 min. (Auto power-saving function)
To resume instrument operation in the previous stateselect the
“OFF” position with the rotary switch and then move the switch to
the desired function.
To cancel auto power-saving function
1. Select the desired function with the rotary switch while holding
down key.
2. The LCD display will change from [APS] to [OFF]and the auto
power-saving function will be disabled.
3. Setting the rotary switch to “OFF” and then reselecting the
desired function will enable the auto power-saving function.
Automatically sets the measurement range to the most appropriate
range (Auto-range function)
Displays [AUTO]
To set the measurement range arbitrarily (Manual-range function)
1. Select the desired function with the rotary switch while holding
down key.
2. Press key to switch the range.
(Can set the range as desiredexcept during continuity testing.)
Indication when input exceeds the measurement range (Overflow indication)
Displays [OF] or [-OF]
Parts Names
RearFront
Jaw
Barrier
Operation grip
LCD Display
Rotary switch
key
HOLD key
(Press to hold the
display value.)
y
ch
Test lead or flexible sensors plug
Example: 3280-10F
Measurement
terminal Battery cover
Warranty
Warranty malfunctions occurring under conditions of normal use in
conformity with the Instruction Manual and Product Precautionary
Markings will be repaired free of charge. This warranty is valid for a
period of three (3) years from the date of purchase. Please contact
the distributor from which you purchased the product for further
information on warranty provisions.
Introduction
Thank you for purchasing the Hioki 3280-10F3280-20F AC Clamp
Meter. To obtain maximum performance from the instrumentplease
read this manual firstand keep it handy for future reference.
3280-10F Average value measurement RMS conversion model
3280-20F True RMS measurement model
Safety Notes
This instrument is designed to conform to IEC 61010 Safety
Standardsand has been thoroughly tested for safety prior to
shipment. Howeverusing the instrument in a way not described in
this manual may negate the provided safety features. Before using
the instrumentbe certain to carefully read the following safety notes.
Notation
In this documentthe risk seriousness and the hazard levels are
classified as follows.
DANGER Imminent risk of operator death or serious injury
WARNING Potential for operator death or serious injury
CAUTION Potential for minor operator injury or device
damage or malfunction
Risk of electric shock
Prohibited actions
Actions that must be performed
Symbols affixed to the device
Precaution or hazard (See corresponding topic.)
Risk of electric shock
Protected throughout by double insulation or reinforced insulation

AC CLAMP METER
Instruction Manual
Nov. 2015 Edition 1
Printed in Japan
3280H961-00 15-11H
3280-10F
3280-20F
EN
Device may be connected to or disconnected from a live conductor
Flexible sensors can be connected to or disconnected from
live conductors when using appropriate protective insulation.
Other sensors can only be connected to or disconnected from
insulated conductors suited to the voltage of the conductor
under measurement.
Grounding
terminal DC (direct current) AC (alternating current)
Measurement categories
This instrument’s current measurement part conforms to the safety
requirements for CAT III 600 Vand the voltage measurement part
conforms to the safety requirements for CAT II 600 VCAT III 300 V
measuring instruments.
Service entrance
Distribution panel
Service drop Internal wiring
Power meter
Fixed Installation
Outlet
CAT IV CAT III CAT II
DANGER
Measuring a location with a higher category number
than the measurement category indicated on this
device may result in a serious accident such as
electric shock.
To avoid electric shockdo not touch the portion
beyond the protective barrier during use.
Never apply voltage to the test leads when the
resistance and continuity functions are selected.
Doing so may damage the instrument and result in
bodily injury. To avoid electrical accidentsremove
power from the circuit before measuring.
WARNING
•To avoid electric shockshort circuits and damage
to the instrumentdisconnect the test leads from the
measurement object before switching the rotary switch.
•To prevent electric shockwhen measuring the voltage
of a power line use a test lead that satisfies the
following criteria:
• Conforms to safety standards IEC61010 or EN61010
• Of measurement category III or IV
• Its rated voltage is higher than the voltage to be measured
• The optional test leads for this instrument conform to the
safety standard EN61010. Use a test lead in accordance
with its defined measurement category and rated voltage.
• Installing the instrument in inappropriate locations may
cause a malfunction of instrument or may give rise to
an accident. Avoid the following locations:
•Exposed to direct sunlight or high temperature
•Exposed to corrosive or combustible gases
•Exposed to a strong electromagnetic field or
electrostatic charge
• Near induction heating systems (such as high-frequency
induction heating systems and IH cooking equipment)
• Susceptible to vibration
•Exposed to wateroilchemicalsor solvents
•Exposed to high humidity or condensation
•Exposed to high quantities of dust particles
WARNING
•Since there is a risk of electric shockcheck that the
insulation on the test lead and flexible sensor (optional) are
neither ripped nor tornand no metal conductor inside the
wire are exposed before using the instrument. If damaged
replace them with those specified by our company.
• To prevent a short circuit accidentbe sure to use the
test leads with the sleeves attached when performing
measurements in the CAT III measurement category.
• If the sleeves are inadvertently removed during
measurementstop the measurement.
• With regard to the electricity supplythere are risks of
electric shockheat generationfireand arc flash due
to short circuits. If persons unfamiliar with electricity
measuring instrument are to use the instrumentanother
person familiar with such instruments must supervise
operations.
•This instrument is measured on a live line. To prevent
electric shockuse appropriate protective insulation and
adhere to applicable laws and regulations.
•Handle and dispose of batteries in accordance with
local regulations.
CAUTION
Do not place foreign objects between the jaw tips (or
flexible loop couplings) or insert foreign objects into the
gaps of the jaws (or flexible loop couplings). Doing so
may worsen the performances of the sensor or interfere
with clamping action.
Poor performance or damage from battery leakage
could result. Observe the cautions listed below:
• Do not use batteries after their recommended expiry date.
• Do not allow weak batteries to remain in the instrument.
• Replace batteries only with the specified type.
• Remove the batteries from the instrument if it is to be
stored for a long time.
•The indicator lights up when the remaining battery
capacity is low. In this casethe instrument's reliability is
not guaranteed. Replace the battery immediately.
•To avoid battery depletionturn the rotary switch OFF
after use (the auto power save feature consumes a small
amount of current).
Inspection Before Measurement
•Verify that the instrument operates normally to ensure that no
damage occurred during storage or shipping. If you find any
damagecontact your authorized Hioki distributor or reseller.
•If damage is suspectedcheck the section below before contacting
your authorized Hioki distributor or reseller.
(1) Check that the test lead is not broken.
Replace with the specified L9208 Test Lead.
(2) Check that the resistance measurement and continuity test
operates normally.
Have the instrument repaired by the your authorized Hioki distributor
or reseller. The instrument may have been subject to a voltage of
greater than 600 V during resistance measurement or continuity
testing.
(3) Check that the battery voltage is not low.
Replace the batteries.
Maintenance/Inspection
Cleaning
• Measurements are degraded by dirt on the mating surfaces of the
jaw (or flexible loop coupling)so keep the surfaces clean by gently
wiping with a softdry cloth.
•To clean the devicewipe it gently with a soft cloth moistened with
water or mild detergent.
•Wipe the LCD display gently with a softdry cloth.
Insert/Replace Batteries
Necessary tool: Phillips screwdriver and CR2032 Coin-shaped lithium battery
NO
OK
12
34
Do not turn the adjustment screw inside the battery case. Doing
so will cause the instrument to report abnormal measured values.
Functions
Display will automatically turn off if the instrument is not used
for 30 min. (Auto power-saving function)
To resume instrument operation in the previous stateselect the
“OFF” position with the rotary switch and then move the switch to
the desired function.
To cancel auto power-saving function
1. Select the desired function with the rotary switch while holding
down key.
2. The LCD display will change from [APS] to [OFF]and the auto
power-saving function will be disabled.
3. Setting the rotary switch to “OFF” and then reselecting the
desired function will enable the auto power-saving function.
Automatically sets the measurement range to the most appropriate
range (Auto-range function)
Displays [AUTO]
To set the measurement range arbitrarily (Manual-range function)
1. Select the desired function with the rotary switch while holding
down key.
2. Press key to switch the range.
(Can set the range as desiredexcept during continuity testing.)
Indication when input exceeds the measurement range (Overflow indication)
Displays [OF] or [-OF]
Parts Names
RearFront
Jaw
Barrier
Operation grip
LCD Display
Rotary switch
key
HOLD key
(Press to hold the
display value.)
y
ch
Test lead or flexible sensors plug
Example: 3280-10F
Measurement
terminal Battery cover
Warranty
Warranty malfunctions occurring under conditions of normal use in
conformity with the Instruction Manual and Product Precautionary
Markings will be repaired free of charge. This warranty is valid for a
period of three (3) years from the date of purchase. Please contact
the distributor from which you purchased the product for further
information on warranty provisions.
Introduction
Thank you for purchasing the Hioki 3280-10F3280-20F AC Clamp
Meter. To obtain maximum performance from the instrumentplease
read this manual firstand keep it handy for future reference.
3280-10F Average value measurement RMS conversion model
3280-20F True RMS measurement model
Safety Notes
This instrument is designed to conform to IEC 61010 Safety
Standardsand has been thoroughly tested for safety prior to
shipment. Howeverusing the instrument in a way not described in
this manual may negate the provided safety features. Before using
the instrumentbe certain to carefully read the following safety notes.
Notation
In this documentthe risk seriousness and the hazard levels are
classified as follows.
DANGER Imminent risk of operator death or serious injury
WARNING Potential for operator death or serious injury
CAUTION Potential for minor operator injury or device
damage or malfunction
Risk of electric shock
Prohibited actions
Actions that must be performed
Symbols affixed to the device
Precaution or hazard (See corresponding topic.)
Risk of electric shock
Protected throughout by double insulation or reinforced insulation

Sleeves
(Red)
(Black)
Test leads AC Flexible Current Sensor *
Cap
(Approx.
7mm)
Cap
Flexible loop
Instruction
plate
*Optional
Measurement Methods
AC Current Measurement [ ]
Measuring with the instrument
1 2
OK NO
3
Measuring with Model CT6280 AC Flexible Current
Sensor (optional)
12 34
Do not pull with excessive force.
Wire band
Do not force the flexible
loop into a bent position.
Do not store while bent.
OK
NO
NO N
NO
NO
Voltage Measurement
AC Voltage Measurement [ ]
123
DC Voltage Measurement [ ]
NO
OK
123
Black(−)Red (+)
Red (+) Black(−)
Resistance Measurement [ ]
21 34
Continuity check [ ]
2134
Specifications
Accuracy
We define measurement tolerances in terms of rdg. (reading) and
dgt. (digit) valueswith the following meanings:
rdg.
(reading or
displayed value)
The value currently being measured and
indicated on the measuring instrument.
dgt.
(resolution)
The smallest displayable unit on a digital
measuring instrumenti.e.the input value
that causes the digital display to show a “1”
as the least-significant digit.
Basic Specifications
Maximum input
current • Jaw (3280-10F3280-20F)
2000 AAC continuous (45 Hz to 66 Hz)
• Flexible loop
(3280-10F+CT6280 or 3280-20F+CT6280)
4200 AAC continuous (50 Hz to 60 Hz)
Maximum input
voltage
600 V AC/DC and 3×106V·Hz or less (ACV/DCV)
Overload
protection 600 V AC/DC (ACV/DCV/Ω/continuity)
Maximum
rated voltage
to earth
• JawCT6280
600 V AC (Measurement category III)
300 V AC (Measurement category IV)
(Anticipated transient overvoltage: 6000 V)
• Voltage measurement terminal
600 V AC (Measurement category II)
300 V AC (Measurement category III)
(Anticipated transient overvoltage: 4000 V)
AC
measurement
method
3280-10F Average value measurement RMS method
3280-20F True RMS measurement method
Display update
rate 400 ms±25 ms
Noise rejection
characteristics NMRR DCV −40 dB or more (50 Hz/60 Hz)
CMRR DCV −100 dB or more
(−50 Hz/60 Hz1 kΩunbalance)
ACV −60 dB or more
(50 Hz/60 Hz1 kΩunbalance)
But−45 dB or more for 600 V range.
Crest factor
(3280-20F only) For 2500 counts or less2.5
Reduces linearly to 1.5 or less at 4200 counts
Zero-display
range 5 counts (AC Currentjaw - flexible loop)
Effects of
conductor
position
• 3280-10F3280-20F: within ±5.0%
• CT6280: within ±5.0%
(At all positions around the sensor’s centerpoint reference)
Maximum
measurable
conductor
diameter
• 3280-10F3280-20F: 33 mm or less
• CT6280: 130 mm or less
General Specifications
Operating
environment Indoorspollution degree 2
altitude up to 2000 m (6562 ft.)
Operating
temperature
and humidity
• Temperature;
−25°C to 65°C (−13.0°F to 149.0°F)
(40 MΩrange: up to 40°C)
• Humidity (no condensation);
Less than 40°C (104.0°F): 80% RH or less
At least 40°C (104.0°F) but less than 45°C (113.0°F):
60% RH or less
At least 45°C (113.0°F) but less than 50°C (122.0°F):
50% RH or less
At least 50°C (122.0°F) but less than 55°C (131.0°F):
40% RH or less
At least 55°C (131.0°F) but less than 60°C (140.0°F):
30% RH or less
At least 60°C (140.0°F) but less than 65°C (149.0°F):
25% RH or less
Storage
temperature
and humidity
−25°C to 65°C (−13°F to 149°F)
80% RH or less (no condensation)
Dustproof and
waterproof IP40 (EN60529)
Drop-proof
distance 1 m on concrete
Standards Safety: EN61010
EMC: EN61326
Power supply CR2032 Coin-shaped lithium battery ×1 (3 V DC)
Maximum rated power: 15 mVA
Continuous
operating time • 3280-10F: Approx. 120 hours
• 3280-20F: Approx. 70 hours
(AC current measurement modecontinuousunloaded)
Dimensions
• 3280-10F3280-20F: Approx. 57W×175H×16D mm
(2.24″W × 6.89″H × 0.63″D)
• CT6280: Approx. 42W×65H×18D mm
(1.65″W × 2.56″H × 0.71″D)
(excluding the flexible loop and output cable)
Mass • 3280-10F3280-20F: Approx. 100 g (3.5 oz.)
(including battery)
• CT6280: Approx. 71 g (2.5 oz.)
Product
warranty period
3280-10F3280-20FCT6280: 3 years
Accessories • 9398 Carrying Case
(C0205 Carrying Case when CT6280 is attached)
• L9208 Test lead
• CR2032 Coin-shaped lithium battery
• Instruction Manual
Options • CT6280 AC Flexible Current Sensor
(Attachment is included)
• 9209 Test Leads Holder
• L4933 Contact Pin Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
• L4934 Small Alligator Clip Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
CALIFORNIAUSA ONLY
This product contains a CR Coin Lithium Battery which
contains Perchlorate Material - special handling may apply.
See www.dtsc.ca.gov/hazardouswaste/perchlorate
Function Specifications
Display Maximum count: 4199 counts
Battery indicator
warning voltage mark lights up at 2.3 V±0.15 V or less
Accuracy Specifications
Conditions of
guaranteed
accuracy
• Guaranteed accuracy period: 1 year (Number of jaw
and flexible loop open/close cycles: 10000 or less)
• Guaranteed accuracy period after adjustment
made by Hioki: 1 year
• Temperature and humidity for guaranteed accuracy:
23°C±5°C (73.0°F±9.0°F)80% RH or less
• Temperature characteristic: Measurement
accuracy × 0.1/°C is added (excluding 23°C±5°C)
AC Current - Jaw (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
42.00 A 4.00 A to 41.99 A ±1.5% rdg.±5 dgt.420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
AC Current - Jaw (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
45 Hz 45 Hz ≤f ≤ 66 Hz 66 Hz < f ≤ 1 kHz
42.00 A 4.00 A to 41.99 A ±2.0% rdg.
±5 dgt. ±1.5% rdg. ±5 dgt. ±2.0% rdg. ±5 dgt.
420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
Accuracy is not defined for currents of 5×105A·Hz or more.
AC Current - Flexible loop (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
420.0 A 40.0 A to 419.9 A ±3.0% rdg.±5 dgt.
(includes accuracy of CT6280 AC
Flexible Current Sensor: ±1.0% rdg.)
4200 A 400 A to 4199 A
AC Current - Flexible loop (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
50 Hz 50 Hz ≤f ≤ 60 Hz 60 Hz < f ≤ 1 kHz
420.0 A 40.0 A to 419.9 A ±3.5% rdg.
±5 dgt.*1*2±3.0% rdg.
±5 dgt.*1±3.5% rdg. ±5 dgt.*1*2
4200 A 400 A to 4199 A
*1: Includes accuracy of CT6280 AC Flexible Current Sensor: ±1.0%
rdg.
*2: Accuracy is not defined for currents of 1000 A or more or
currents of 5×105A·Hz or more.
AC Voltage
Range Accuracy range Accuracy Input
impedance
45 Hz ≤f ≤66
Hz 66 Hz < f ≤ 500 Hz
4.200 V 0.400 V to 4.199 V ±1.8% rdg.
±7 dgt. ±2.3% rdg. ±8 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
DC Voltage
Range Accuracy range Accuracy Input impedance
420.0 mV 40.0 mV to 419.9 mV ±2.5% rdg.
±5 dgt. 100 MΩor more
4.200 V 0.400 V to 4.199 V ±1.0% rdg.
±3 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
Resistance
Range Accuracy range Accuracy
Open circuit
voltage
420.0 Ω40.0 Ωto 419.9 Ω
±2.0% rdg.±4 dgt. 3.4 V or
less
4.200 kΩ0.400 kΩto 4.199 kΩ
42.00 kΩ4.00 kΩto 41.99 kΩ
420.0 kΩ40.0 kΩto 419.9 kΩ
4.200 MΩ0.400 MΩto 4.199 MΩ±5.0% rdg.±4 dgt.
42.00 MΩ4.00 MΩto 41.99 MΩ±10.0% rdg.±4 dgt.
Continuity Check
Range Accuracy Threshold of
buzzer sound Open circuit voltage
420.0 Ω±2.0% rdg.±4 dgt. 50 Ω±40 Ωor
less 3.4 V or less

Sleeves
(Red)
(Black)
Test leads AC Flexible Current Sensor *
Cap
(Approx.
7mm)
Cap
Flexible loop
Instruction
plate
*Optional
Measurement Methods
AC Current Measurement [ ]
Measuring with the instrument
1 2
OK NO
3
Measuring with Model CT6280 AC Flexible Current
Sensor (optional)
12 34
Do not pull with excessive force.
Wire band
Do not force the flexible
loop into a bent position.
Do not store while bent.
OK
NO
NO N
NO
NO
Voltage Measurement
AC Voltage Measurement [ ]
123
DC Voltage Measurement [ ]
NO
OK
123
Black(−)Red (+)
Red (+) Black(−)
Resistance Measurement [ ]
21 34
Continuity check [ ]
2134
Specifications
Accuracy
We define measurement tolerances in terms of rdg. (reading) and
dgt. (digit) valueswith the following meanings:
rdg.
(reading or
displayed value)
The value currently being measured and
indicated on the measuring instrument.
dgt.
(resolution)
The smallest displayable unit on a digital
measuring instrumenti.e.the input value
that causes the digital display to show a “1”
as the least-significant digit.
Basic Specifications
Maximum input
current • Jaw (3280-10F3280-20F)
2000 AAC continuous (45 Hz to 66 Hz)
• Flexible loop
(3280-10F+CT6280 or 3280-20F+CT6280)
4200 AAC continuous (50 Hz to 60 Hz)
Maximum input
voltage
600 V AC/DC and 3×106V·Hz or less (ACV/DCV)
Overload
protection 600 V AC/DC (ACV/DCV/Ω/continuity)
Maximum
rated voltage
to earth
• JawCT6280
600 V AC (Measurement category III)
300 V AC (Measurement category IV)
(Anticipated transient overvoltage: 6000 V)
• Voltage measurement terminal
600 V AC (Measurement category II)
300 V AC (Measurement category III)
(Anticipated transient overvoltage: 4000 V)
AC
measurement
method
3280-10F Average value measurement RMS method
3280-20F True RMS measurement method
Display update
rate 400 ms±25 ms
Noise rejection
characteristics NMRR DCV −40 dB or more (50 Hz/60 Hz)
CMRR DCV −100 dB or more
(−50 Hz/60 Hz1 kΩunbalance)
ACV −60 dB or more
(50 Hz/60 Hz1 kΩunbalance)
But−45 dB or more for 600 V range.
Crest factor
(3280-20F only) For 2500 counts or less2.5
Reduces linearly to 1.5 or less at 4200 counts
Zero-display
range 5 counts (AC Currentjaw - flexible loop)
Effects of
conductor
position
• 3280-10F3280-20F: within ±5.0%
• CT6280: within ±5.0%
(At all positions around the sensor’s centerpoint reference)
Maximum
measurable
conductor
diameter
• 3280-10F3280-20F: 33 mm or less
• CT6280: 130 mm or less
General Specifications
Operating
environment Indoorspollution degree 2
altitude up to 2000 m (6562 ft.)
Operating
temperature
and humidity
• Temperature;
−25°C to 65°C (−13.0°F to 149.0°F)
(40 MΩrange: up to 40°C)
• Humidity (no condensation);
Less than 40°C (104.0°F): 80% RH or less
At least 40°C (104.0°F) but less than 45°C (113.0°F):
60% RH or less
At least 45°C (113.0°F) but less than 50°C (122.0°F):
50% RH or less
At least 50°C (122.0°F) but less than 55°C (131.0°F):
40% RH or less
At least 55°C (131.0°F) but less than 60°C (140.0°F):
30% RH or less
At least 60°C (140.0°F) but less than 65°C (149.0°F):
25% RH or less
Storage
temperature
and humidity
−25°C to 65°C (−13°F to 149°F)
80% RH or less (no condensation)
Dustproof and
waterproof IP40 (EN60529)
Drop-proof
distance 1 m on concrete
Standards Safety: EN61010
EMC: EN61326
Power supply CR2032 Coin-shaped lithium battery ×1 (3 V DC)
Maximum rated power: 15 mVA
Continuous
operating time • 3280-10F: Approx. 120 hours
• 3280-20F: Approx. 70 hours
(AC current measurement modecontinuousunloaded)
Dimensions
• 3280-10F3280-20F: Approx. 57W×175H×16D mm
(2.24″W × 6.89″H × 0.63″D)
• CT6280: Approx. 42W×65H×18D mm
(1.65″W × 2.56″H × 0.71″D)
(excluding the flexible loop and output cable)
Mass • 3280-10F3280-20F: Approx. 100 g (3.5 oz.)
(including battery)
• CT6280: Approx. 71 g (2.5 oz.)
Product
warranty period
3280-10F3280-20FCT6280: 3 years
Accessories • 9398 Carrying Case
(C0205 Carrying Case when CT6280 is attached)
• L9208 Test lead
• CR2032 Coin-shaped lithium battery
• Instruction Manual
Options • CT6280 AC Flexible Current Sensor
(Attachment is included)
• 9209 Test Leads Holder
• L4933 Contact Pin Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
• L4934 Small Alligator Clip Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
CALIFORNIAUSA ONLY
This product contains a CR Coin Lithium Battery which
contains Perchlorate Material - special handling may apply.
See www.dtsc.ca.gov/hazardouswaste/perchlorate
Function Specifications
Display Maximum count: 4199 counts
Battery indicator
warning voltage mark lights up at 2.3 V±0.15 V or less
Accuracy Specifications
Conditions of
guaranteed
accuracy
• Guaranteed accuracy period: 1 year (Number of jaw
and flexible loop open/close cycles: 10000 or less)
• Guaranteed accuracy period after adjustment
made by Hioki: 1 year
• Temperature and humidity for guaranteed accuracy:
23°C±5°C (73.0°F±9.0°F)80% RH or less
• Temperature characteristic: Measurement
accuracy × 0.1/°C is added (excluding 23°C±5°C)
AC Current - Jaw (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
42.00 A 4.00 A to 41.99 A ±1.5% rdg.±5 dgt.420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
AC Current - Jaw (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
45 Hz 45 Hz ≤f ≤ 66 Hz 66 Hz < f ≤ 1 kHz
42.00 A 4.00 A to 41.99 A ±2.0% rdg.
±5 dgt. ±1.5% rdg. ±5 dgt. ±2.0% rdg. ±5 dgt.
420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
Accuracy is not defined for currents of 5×105A·Hz or more.
AC Current - Flexible loop (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
420.0 A 40.0 A to 419.9 A ±3.0% rdg.±5 dgt.
(includes accuracy of CT6280 AC
Flexible Current Sensor: ±1.0% rdg.)
4200 A 400 A to 4199 A
AC Current - Flexible loop (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
50 Hz 50 Hz ≤f ≤ 60 Hz 60 Hz < f ≤ 1 kHz
420.0 A 40.0 A to 419.9 A ±3.5% rdg.
±5 dgt.*1*2±3.0% rdg.
±5 dgt.*1±3.5% rdg. ±5 dgt.*1*2
4200 A 400 A to 4199 A
*1: Includes accuracy of CT6280 AC Flexible Current Sensor: ±1.0%
rdg.
*2: Accuracy is not defined for currents of 1000 A or more or
currents of 5×105A·Hz or more.
AC Voltage
Range Accuracy range Accuracy Input
impedance
45 Hz ≤f ≤66
Hz 66 Hz < f ≤ 500 Hz
4.200 V 0.400 V to 4.199 V ±1.8% rdg.
±7 dgt. ±2.3% rdg. ±8 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
DC Voltage
Range Accuracy range Accuracy Input impedance
420.0 mV 40.0 mV to 419.9 mV ±2.5% rdg.
±5 dgt. 100 MΩor more
4.200 V 0.400 V to 4.199 V ±1.0% rdg.
±3 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
Resistance
Range Accuracy range Accuracy
Open circuit
voltage
420.0 Ω40.0 Ωto 419.9 Ω
±2.0% rdg.±4 dgt. 3.4 V or
less
4.200 kΩ0.400 kΩto 4.199 kΩ
42.00 kΩ4.00 kΩto 41.99 kΩ
420.0 kΩ40.0 kΩto 419.9 kΩ
4.200 MΩ0.400 MΩto 4.199 MΩ±5.0% rdg.±4 dgt.
42.00 MΩ4.00 MΩto 41.99 MΩ±10.0% rdg.±4 dgt.
Continuity Check
Range Accuracy Threshold of
buzzer sound Open circuit voltage
420.0 Ω±2.0% rdg.±4 dgt. 50 Ω±40 Ωor
less 3.4 V or less

Sleeves
(Red)
(Black)
Test leads AC Flexible Current Sensor *
Cap
(Approx.
7mm)
Cap
Flexible loop
Instruction
plate
*Optional
Measurement Methods
AC Current Measurement [ ]
Measuring with the instrument
1 2
OK NO
3
Measuring with Model CT6280 AC Flexible Current
Sensor (optional)
12 34
Do not pull with excessive force.
Wire band
Do not force the flexible
loop into a bent position.
Do not store while bent.
OK
NO
NO N
NO
NO
Voltage Measurement
AC Voltage Measurement [ ]
123
DC Voltage Measurement [ ]
NO
OK
123
Black(−)Red (+)
Red (+) Black(−)
Resistance Measurement [ ]
21 34
Continuity check [ ]
2134
Specifications
Accuracy
We define measurement tolerances in terms of rdg. (reading) and
dgt. (digit) valueswith the following meanings:
rdg.
(reading or
displayed value)
The value currently being measured and
indicated on the measuring instrument.
dgt.
(resolution)
The smallest displayable unit on a digital
measuring instrumenti.e.the input value
that causes the digital display to show a “1”
as the least-significant digit.
Basic Specifications
Maximum input
current • Jaw (3280-10F3280-20F)
2000 AAC continuous (45 Hz to 66 Hz)
• Flexible loop
(3280-10F+CT6280 or 3280-20F+CT6280)
4200 AAC continuous (50 Hz to 60 Hz)
Maximum input
voltage
600 V AC/DC and 3×106V·Hz or less (ACV/DCV)
Overload
protection 600 V AC/DC (ACV/DCV/Ω/continuity)
Maximum
rated voltage
to earth
• JawCT6280
600 V AC (Measurement category III)
300 V AC (Measurement category IV)
(Anticipated transient overvoltage: 6000 V)
• Voltage measurement terminal
600 V AC (Measurement category II)
300 V AC (Measurement category III)
(Anticipated transient overvoltage: 4000 V)
AC
measurement
method
3280-10F Average value measurement RMS method
3280-20F True RMS measurement method
Display update
rate 400 ms±25 ms
Noise rejection
characteristics NMRR DCV −40 dB or more (50 Hz/60 Hz)
CMRR DCV −100 dB or more
(−50 Hz/60 Hz1 kΩunbalance)
ACV −60 dB or more
(50 Hz/60 Hz1 kΩunbalance)
But−45 dB or more for 600 V range.
Crest factor
(3280-20F only) For 2500 counts or less2.5
Reduces linearly to 1.5 or less at 4200 counts
Zero-display
range 5 counts (AC Currentjaw - flexible loop)
Effects of
conductor
position
• 3280-10F3280-20F: within ±5.0%
• CT6280: within ±5.0%
(At all positions around the sensor’s centerpoint reference)
Maximum
measurable
conductor
diameter
• 3280-10F3280-20F: 33 mm or less
• CT6280: 130 mm or less
General Specifications
Operating
environment Indoorspollution degree 2
altitude up to 2000 m (6562 ft.)
Operating
temperature
and humidity
• Temperature;
−25°C to 65°C (−13.0°F to 149.0°F)
(40 MΩrange: up to 40°C)
• Humidity (no condensation);
Less than 40°C (104.0°F): 80% RH or less
At least 40°C (104.0°F) but less than 45°C (113.0°F):
60% RH or less
At least 45°C (113.0°F) but less than 50°C (122.0°F):
50% RH or less
At least 50°C (122.0°F) but less than 55°C (131.0°F):
40% RH or less
At least 55°C (131.0°F) but less than 60°C (140.0°F):
30% RH or less
At least 60°C (140.0°F) but less than 65°C (149.0°F):
25% RH or less
Storage
temperature
and humidity
−25°C to 65°C (−13°F to 149°F)
80% RH or less (no condensation)
Dustproof and
waterproof IP40 (EN60529)
Drop-proof
distance 1 m on concrete
Standards Safety: EN61010
EMC: EN61326
Power supply CR2032 Coin-shaped lithium battery ×1 (3 V DC)
Maximum rated power: 15 mVA
Continuous
operating time • 3280-10F: Approx. 120 hours
• 3280-20F: Approx. 70 hours
(AC current measurement modecontinuousunloaded)
Dimensions
• 3280-10F3280-20F: Approx. 57W×175H×16D mm
(2.24″W × 6.89″H × 0.63″D)
• CT6280: Approx. 42W×65H×18D mm
(1.65″W × 2.56″H × 0.71″D)
(excluding the flexible loop and output cable)
Mass • 3280-10F3280-20F: Approx. 100 g (3.5 oz.)
(including battery)
• CT6280: Approx. 71 g (2.5 oz.)
Product
warranty period
3280-10F3280-20FCT6280: 3 years
Accessories • 9398 Carrying Case
(C0205 Carrying Case when CT6280 is attached)
• L9208 Test lead
• CR2032 Coin-shaped lithium battery
• Instruction Manual
Options • CT6280 AC Flexible Current Sensor
(Attachment is included)
• 9209 Test Leads Holder
• L4933 Contact Pin Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
• L4934 Small Alligator Clip Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
CALIFORNIAUSA ONLY
This product contains a CR Coin Lithium Battery which
contains Perchlorate Material - special handling may apply.
See www.dtsc.ca.gov/hazardouswaste/perchlorate
Function Specifications
Display Maximum count: 4199 counts
Battery indicator
warning voltage mark lights up at 2.3 V±0.15 V or less
Accuracy Specifications
Conditions of
guaranteed
accuracy
• Guaranteed accuracy period: 1 year (Number of jaw
and flexible loop open/close cycles: 10000 or less)
• Guaranteed accuracy period after adjustment
made by Hioki: 1 year
• Temperature and humidity for guaranteed accuracy:
23°C±5°C (73.0°F±9.0°F)80% RH or less
• Temperature characteristic: Measurement
accuracy × 0.1/°C is added (excluding 23°C±5°C)
AC Current - Jaw (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
42.00 A 4.00 A to 41.99 A ±1.5% rdg.±5 dgt.420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
AC Current - Jaw (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
45 Hz 45 Hz ≤f ≤ 66 Hz 66 Hz < f ≤ 1 kHz
42.00 A 4.00 A to 41.99 A ±2.0% rdg.
±5 dgt. ±1.5% rdg. ±5 dgt. ±2.0% rdg. ±5 dgt.
420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
Accuracy is not defined for currents of 5×105A·Hz or more.
AC Current - Flexible loop (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
420.0 A 40.0 A to 419.9 A ±3.0% rdg.±5 dgt.
(includes accuracy of CT6280 AC
Flexible Current Sensor: ±1.0% rdg.)
4200 A 400 A to 4199 A
AC Current - Flexible loop (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
50 Hz 50 Hz ≤f ≤ 60 Hz 60 Hz < f ≤ 1 kHz
420.0 A 40.0 A to 419.9 A ±3.5% rdg.
±5 dgt.*1*2±3.0% rdg.
±5 dgt.*1±3.5% rdg. ±5 dgt.*1*2
4200 A 400 A to 4199 A
*1: Includes accuracy of CT6280 AC Flexible Current Sensor: ±1.0%
rdg.
*2: Accuracy is not defined for currents of 1000 A or more or
currents of 5×105A·Hz or more.
AC Voltage
Range Accuracy range Accuracy Input
impedance
45 Hz ≤f ≤66
Hz 66 Hz < f ≤ 500 Hz
4.200 V 0.400 V to 4.199 V ±1.8% rdg.
±7 dgt. ±2.3% rdg. ±8 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
DC Voltage
Range Accuracy range Accuracy Input impedance
420.0 mV 40.0 mV to 419.9 mV ±2.5% rdg.
±5 dgt. 100 MΩor more
4.200 V 0.400 V to 4.199 V ±1.0% rdg.
±3 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
Resistance
Range Accuracy range Accuracy
Open circuit
voltage
420.0 Ω40.0 Ωto 419.9 Ω
±2.0% rdg.±4 dgt. 3.4 V or
less
4.200 kΩ0.400 kΩto 4.199 kΩ
42.00 kΩ4.00 kΩto 41.99 kΩ
420.0 kΩ40.0 kΩto 419.9 kΩ
4.200 MΩ0.400 MΩto 4.199 MΩ±5.0% rdg.±4 dgt.
42.00 MΩ4.00 MΩto 41.99 MΩ±10.0% rdg.±4 dgt.
Continuity Check
Range Accuracy Threshold of
buzzer sound Open circuit voltage
420.0 Ω±2.0% rdg.±4 dgt. 50 Ω±40 Ωor
less 3.4 V or less

Sleeves
(Red)
(Black)
Test leads AC Flexible Current Sensor *
Cap
(Approx.
7mm)
Cap
Flexible loop
Instruction
plate
*Optional
Measurement Methods
AC Current Measurement [ ]
Measuring with the instrument
1 2
OK NO
3
Measuring with Model CT6280 AC Flexible Current
Sensor (optional)
12 34
Do not pull with excessive force.
Wire band
Do not force the flexible
loop into a bent position.
Do not store while bent.
OK
NO
NO N
NO
NO
Voltage Measurement
AC Voltage Measurement [ ]
123
DC Voltage Measurement [ ]
NO
OK
123
Black(−)Red (+)
Red (+) Black(−)
Resistance Measurement [ ]
21 34
Continuity check [ ]
2134
Specifications
Accuracy
We define measurement tolerances in terms of rdg. (reading) and
dgt. (digit) valueswith the following meanings:
rdg.
(reading or
displayed value)
The value currently being measured and
indicated on the measuring instrument.
dgt.
(resolution)
The smallest displayable unit on a digital
measuring instrumenti.e.the input value
that causes the digital display to show a “1”
as the least-significant digit.
Basic Specifications
Maximum input
current • Jaw (3280-10F3280-20F)
2000 AAC continuous (45 Hz to 66 Hz)
• Flexible loop
(3280-10F+CT6280 or 3280-20F+CT6280)
4200 AAC continuous (50 Hz to 60 Hz)
Maximum input
voltage
600 V AC/DC and 3×106V·Hz or less (ACV/DCV)
Overload
protection 600 V AC/DC (ACV/DCV/Ω/continuity)
Maximum
rated voltage
to earth
• JawCT6280
600 V AC (Measurement category III)
300 V AC (Measurement category IV)
(Anticipated transient overvoltage: 6000 V)
• Voltage measurement terminal
600 V AC (Measurement category II)
300 V AC (Measurement category III)
(Anticipated transient overvoltage: 4000 V)
AC
measurement
method
3280-10F Average value measurement RMS method
3280-20F True RMS measurement method
Display update
rate 400 ms±25 ms
Noise rejection
characteristics NMRR DCV −40 dB or more (50 Hz/60 Hz)
CMRR DCV −100 dB or more
(−50 Hz/60 Hz1 kΩunbalance)
ACV −60 dB or more
(50 Hz/60 Hz1 kΩunbalance)
But−45 dB or more for 600 V range.
Crest factor
(3280-20F only) For 2500 counts or less2.5
Reduces linearly to 1.5 or less at 4200 counts
Zero-display
range 5 counts (AC Currentjaw - flexible loop)
Effects of
conductor
position
• 3280-10F3280-20F: within ±5.0%
• CT6280: within ±5.0%
(At all positions around the sensor’s centerpoint reference)
Maximum
measurable
conductor
diameter
• 3280-10F3280-20F: 33 mm or less
• CT6280: 130 mm or less
General Specifications
Operating
environment Indoorspollution degree 2
altitude up to 2000 m (6562 ft.)
Operating
temperature
and humidity
• Temperature;
−25°C to 65°C (−13.0°F to 149.0°F)
(40 MΩrange: up to 40°C)
• Humidity (no condensation);
Less than 40°C (104.0°F): 80% RH or less
At least 40°C (104.0°F) but less than 45°C (113.0°F):
60% RH or less
At least 45°C (113.0°F) but less than 50°C (122.0°F):
50% RH or less
At least 50°C (122.0°F) but less than 55°C (131.0°F):
40% RH or less
At least 55°C (131.0°F) but less than 60°C (140.0°F):
30% RH or less
At least 60°C (140.0°F) but less than 65°C (149.0°F):
25% RH or less
Storage
temperature
and humidity
−25°C to 65°C (−13°F to 149°F)
80% RH or less (no condensation)
Dustproof and
waterproof IP40 (EN60529)
Drop-proof
distance 1 m on concrete
Standards Safety: EN61010
EMC: EN61326
Power supply CR2032 Coin-shaped lithium battery ×1 (3 V DC)
Maximum rated power: 15 mVA
Continuous
operating time • 3280-10F: Approx. 120 hours
• 3280-20F: Approx. 70 hours
(AC current measurement modecontinuousunloaded)
Dimensions
• 3280-10F3280-20F: Approx. 57W×175H×16D mm
(2.24″W × 6.89″H × 0.63″D)
• CT6280: Approx. 42W×65H×18D mm
(1.65″W × 2.56″H × 0.71″D)
(excluding the flexible loop and output cable)
Mass • 3280-10F3280-20F: Approx. 100 g (3.5 oz.)
(including battery)
• CT6280: Approx. 71 g (2.5 oz.)
Product
warranty period
3280-10F3280-20FCT6280: 3 years
Accessories • 9398 Carrying Case
(C0205 Carrying Case when CT6280 is attached)
• L9208 Test lead
• CR2032 Coin-shaped lithium battery
• Instruction Manual
Options • CT6280 AC Flexible Current Sensor
(Attachment is included)
• 9209 Test Leads Holder
• L4933 Contact Pin Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
• L4934 Small Alligator Clip Set
(Can be connected to the tip of the L9208which
comes with the instrument.)
CALIFORNIAUSA ONLY
This product contains a CR Coin Lithium Battery which
contains Perchlorate Material - special handling may apply.
See www.dtsc.ca.gov/hazardouswaste/perchlorate
Function Specifications
Display Maximum count: 4199 counts
Battery indicator
warning voltage mark lights up at 2.3 V±0.15 V or less
Accuracy Specifications
Conditions of
guaranteed
accuracy
• Guaranteed accuracy period: 1 year (Number of jaw
and flexible loop open/close cycles: 10000 or less)
• Guaranteed accuracy period after adjustment
made by Hioki: 1 year
• Temperature and humidity for guaranteed accuracy:
23°C±5°C (73.0°F±9.0°F)80% RH or less
• Temperature characteristic: Measurement
accuracy × 0.1/°C is added (excluding 23°C±5°C)
AC Current - Jaw (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
42.00 A 4.00 A to 41.99 A ±1.5% rdg.±5 dgt.420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
AC Current - Jaw (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
45 Hz 45 Hz ≤f ≤ 66 Hz 66 Hz < f ≤ 1 kHz
42.00 A 4.00 A to 41.99 A ±2.0% rdg.
±5 dgt. ±1.5% rdg. ±5 dgt. ±2.0% rdg. ±5 dgt.
420.0 A 40.0 A to 419.9 A
1000 A 100 A to 1000 A
Accuracy is not defined for currents of 5×105A·Hz or more.
AC Current - Flexible loop (3280-10F)
Range Accuracy range Accuracy
50 Hz ≤f ≤60 Hz
420.0 A 40.0 A to 419.9 A ±3.0% rdg.±5 dgt.
(includes accuracy of CT6280 AC
Flexible Current Sensor: ±1.0% rdg.)
4200 A 400 A to 4199 A
AC Current - Flexible loop (3280-20F)
Range Accuracy range Accuracy
40 Hz ≤f <
50 Hz 50 Hz ≤f ≤ 60 Hz 60 Hz < f ≤ 1 kHz
420.0 A 40.0 A to 419.9 A ±3.5% rdg.
±5 dgt.*1*2±3.0% rdg.
±5 dgt.*1±3.5% rdg. ±5 dgt.*1*2
4200 A 400 A to 4199 A
*1: Includes accuracy of CT6280 AC Flexible Current Sensor: ±1.0%
rdg.
*2: Accuracy is not defined for currents of 1000 A or more or
currents of 5×105A·Hz or more.
AC Voltage
Range Accuracy range Accuracy Input
impedance
45 Hz ≤f ≤66
Hz 66 Hz < f ≤ 500 Hz
4.200 V 0.400 V to 4.199 V ±1.8% rdg.
±7 dgt. ±2.3% rdg. ±8 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
DC Voltage
Range Accuracy range Accuracy Input impedance
420.0 mV 40.0 mV to 419.9 mV ±2.5% rdg.
±5 dgt. 100 MΩor more
4.200 V 0.400 V to 4.199 V ±1.0% rdg.
±3 dgt.
11 MΩ±5%
42.00 V 4.00 V to 41.99 V 10 MΩ±5%
420.0 V 40.0 V to 419.9 V 10 MΩ±5%
600 V 400 V to 600 V 10 MΩ±5%
Resistance
Range Accuracy range Accuracy
Open circuit
voltage
420.0 Ω40.0 Ωto 419.9 Ω
±2.0% rdg.±4 dgt. 3.4 V or
less
4.200 kΩ0.400 kΩto 4.199 kΩ
42.00 kΩ4.00 kΩto 41.99 kΩ
420.0 kΩ40.0 kΩto 419.9 kΩ
4.200 MΩ0.400 MΩto 4.199 MΩ±5.0% rdg.±4 dgt.
42.00 MΩ4.00 MΩto 41.99 MΩ±10.0% rdg.±4 dgt.
Continuity Check
Range Accuracy Threshold of
buzzer sound Open circuit voltage
420.0 Ω±2.0% rdg.±4 dgt. 50 Ω±40 Ωor
less 3.4 V or less