Hioki 3256-50, 3256-51, 3257-50, 3257-51 Instruction Manual

INSTRUCTION MANUAL

3256-50
3256-51

DIGITAL HiTESTER

i

Contents

Introduction .............................................................1

Inspection ............................................................... 1

Safety Notes ...........................................................2

Usage Notes........................................................... 6

Chapter 1 Overview 9

1.1 Product Overv iew ........................... ...... ..9

1.2 Features ..................................................9

1.3 Parts Names and Functions .................10

Chapter 2 Measurement Procedures 15

2.1 Voltage Meas urem en t........................... 16

2.2 Frequency Measurement...................... 18

2.3 Current Measurement........................... 19

2.4 Resistance Measurement..................... 22

2.5 Continuity Chec k............. ...... ...... .......... 23

2.6 Diode Check......................................... 24

Chapter 3 Additional Functions 25

3.1 HOLD AUTO Function ..........................25

3.2 HOLD Function .............. ...... .................26

3.3 Overflow Warning Function ..................27

3.4 Relative Display Function .....................28

3.5 Auto Power Save Function ................... 30

3.6 Voltage Detecti ng Func ti on ...................31

3.7 Dynamic Recording Function ................32

3.8 Memory Function ..................................33

ii

Chapter 4 Specificatio ns 35

4.1 General Specifications ..........................35

4.2 Accuracy ................................................39

Chapter 5 Maintena ce and Service 43

5.1 Replacing the Batteries and Fuses ........43

5.2 Cleaning ................................................45

5.3 Service ..................................................45

1

Introduction

Thank you for purchasing the HIOKI "3256-50/51
DIGITAL HiTESTER". To obtain maximum perfor­mance from the product, please read th is manual
first, and keep it handy for future reference.

Inspection

• When you receive the product, inspect it carefully
to ensure that no damage occurred during ship­ping. In particular, check the accessories, panel
switches, and connectors. If damage is evident, or
if it fails to operate according to the specifications,
contact your dealer or Hioki representative.

• Before using the product the first time, verify that it
operates normally to ensure that the no damage
occurred during storage or shipping. If you find any
damage, contact your dealer or Hioki representa­tive.

• Before using the product, make sure that the insu­lation on the test leads is undamaged and that no
bare conductors are improperly exposed. Using
the product under such conditions could result in
electrocution. Replace the test leads and probes
with the specified Hioki Model 9207-10.

2

Accessories

3256-50

*1

3256-51

Safety Notes

This manual contains information and warnings
essential for safe operation of the product and for
maintaining it in safe operating condition. Before
using the product, be sure to carefully read the fol­lowing safety notes.

9207-10 TEST LEAD .................. 1

*2

Instruction Manual....................... 1

R03 Manganese battery..............2

(Supplied with this product, for
monitor)

9378 CARRYING CASE
(3256-50 only)

Protective holster

*2

(3256-51only)

*1

This product is designed to conform to IEC
61010 Safety Standards, and has been thor­oughly tested for safety prior to shipment.
However, mishandling during use could
result in injury or death, as well as damage to
the product. Be certain that you understand
the instructions and precautions in the man­ual before use. We disclaim any responsibil­ity for accidents or injuries not resulting
directly from product defects.

3

Safety Symbols

In the manual, the symbol indicates particu­larly important information that the user should
read before using the product.

The symbol printed on the product indicates
that the user should refer to a corresponding topic
in the manual (marked with the symbol) before
using the relevant function.

Indicates that dangerous voltage may be present
at this terminal.

Indicates a double-insulated device.

Indicates a grounding terminal.

Indicates DC (Direct Current).
Indicates AC (Alternating Current).

Indicates DC (Direct Current) or AC (Alternating
Current).

4

The following symbols in this manual indicate the
relative importance of cautions and warnings.

Indicates that incorrect operation presents an ex­treme hazard that could result in serious injury or
death to the user.

Indicates that incorrect operation presents a sig­nificant hazard that could result in serious injury or
death to the user.

Indicates that incorrect operation presents a pos­sibility of injury to t he user or damage to the prod­uct.

Advisory items related to performance or correct
operation of the product.

Other Symbols

❖

Accuracy

f.s.

rdg.

Indicates the quick guide for operations

Indicates the prohibited action

Indicates the reference

We define measurement tolerances in terms of f.s.
(full scale), rdg. (reading) and dgt. (digit) values,
with the following meanings:

(maximum display value or scale length)
The maximum displayable value or the full length
of the scale. This is usually the maximum value of
the currently selected range.

(reading or displayed value)
The value currently being measured and indicated
on the measuring product.

(resolution)

dgt.

The smallest displayable unit on a digital measur­ing product, i.e., the input value that causes the
digital display to show a "1".

5

Measurement categories (Overvoltage categories)

This product complies with CATIII (600 V), CATII (1000 V) safety
requirements.
To ensure safe operation of measurement products, IEC 61010
establishes safety standards for various electrical environments,
categorized as CAT I to CAT IV, and called measurement cate­gories. These are defined as follows.

CAT I

Secondary electrical circuits connected to an AC elec­trical outlet through a transformer or similar device.

Primary electrical circuits in equipment connected to

CAT II

an AC electrical outlet by a power cord (portable tools,
household appliances, etc.)

Primary electrical circuits of heavy equipment (fixed

CAT III

installations) connected directly to the distribution
panel, and feeders from the distribution panel to out­lets.

The circuit from the service drop to the service en-

CAT IV

trance, and to the power meter and primary overcur­rent protection device (distribution panel).

Higher-numbered categories correspond to electrical environ­ments with greater momentary energy. So a measurement
device designed for CAT III environments can endure greater
momentary energy than a device designed for CAT II.
Using a measurement product in an environment designated
with a higher-numbered category than that for which the product
is rated could result in a sev ere accident, and mus t be carefully
avoided.
Never use a CAT I measuring product in CAT II, III, or IV envi­ronments.
The measurement categories comply with the Overvoltage Cate­gories of the IEC60664 Standards.

6

Usage Notes

Follow these precautions to ensure safe operation
and to obtain the full benefits of the various func­tions.

• To avoid electric shock, do not allow the
product to get wet, and do not use it when
your hands are wet.

• Do not use the product where it may be
exposed to corrosive or combustible
gases. The product may be damaged or
cause an explosion.

7

Direct

-

st

-

n

n

sunlight

High temper
ature, high
humidity, du

Observe the following to avoid damage to the
product.

• Installation and Operating Environment
Between 0°C and 40°C; 80% RH or less;
indoors only. Howev er, it can be safely operated
at as low as -10°C.

• Do not store or use the product where it could
be exposed to direct sunlight, high tem perature
or humidity, or condensation. Under suc h condi­tions, the product may be damaged and insula­tion may deteriorate so that it no longer meets
specifications.

• This product is not designed to be entirely
water- or dust-proof. To avoid damage, do not
use it in a wet or dusty environment.

• Do not use the product near a device that gener­ates a strong electromagnetic field or electro-

Electromag

etic radiatio

static charge, as these may cause erroneous
measurements.

• To avoid damage to the product, protect it from
vibration or shock during transport and handling,
and be especially careful to avoid dropping.

• Adjustments and repairs should be made only

Impact,

dropping

by technically qualified personnel.

• If the protective functions of the product are
damaged, either remove it from service or mark
it clearly so that others do not use it inadvert­ently.

• To avoid corrosion from battery leakage, remove
the batteries from the product if it is to be st ored
for a long time.

8

• Accurate measurement may be impossible in the
presence of strong magnetic fields, such as near
transformers and high-current conductors, or in
the presence of strong electromagnetic fields
such as near radio transmitters.

• To avoid battery depletion, turn the function
selector OFF after use (the Auto Power Save
feature consumes a small amount of current).

• The indicator appears when battery voltage
becomes low. Replace the batteries as soon as
possible.

9

1.1 Product Ov e r view

Overview Chapter 1

1.1 Product Overview

This measurement product is a multi-functional
digital multimeter capable of measuring DC and
AC voltages, DC and AC currents, and the resis­tance, checking the diode and continuity, and
detecting voltage.

1.2 Features

Compliance with CE marking requirements

The measurement product is designed to comply
with the international safety standard (IEC61010-

1) and EMC standards.

Safety-designed handy digital multimeter

The measurement product is equipped with test­lead misinsertion preventive shutters and fast -act­ing fuses at the current measurement terminals.

Multi-functional and voltage detecting

• Live conductors can be examined safely and easily.

• The Hold Auto function allows measur ed v alue s to
be maintained by simply disconnecting the test
leads.

• The Hold function maintains the displayed value.

• The Memory function saves the held value dis­played.

• The Recording function displays the maximum,
minimum, average, and currently measured values
selectively.

• The Relative function displays any discrepancy
from the reference.

1.3 Parts Names and Functions

10

1.3 Parts Names and Functions

*: for details, see
the following
pages

REC•MEMO

Button

(Press this button
to change to the
function indi ca t­ed in blue.)

For other func­tions, see the fol­lowing pages.

LCD display *

H.AUTO/REL

Button *

RANGE

Button *

V.Ω terminal

Terminal used to
measure volta g­es and resis­tances

(red test lead)

COM terminal

Terminal com mon to
all functions

(black test lead)

The terminal shutter works together with the
function selector to prevent incorrect operation.
Note that if the function selector is toggled with
the test leads connected, the measurement
product may be damaged.

Function
Selector

(Selects functions
and turns the
power on/off)

A terminal

Terminal used to
measure currents
in 10-A mode

μA.mA terminal

Terminal used to 
measure currents in

μA/mA mode

11

1.3 Parts Names and Functions

LCD(Display)

n
n

r

d

s

k

­s

-

)

­)

-

Indicates HOLD AUTO/

HOLD function

Indicates Relative functio n
Indicates Autorang ing

function
Indicates DC

voltage/cur­rent function

Indicates AC
voltage/cur­rent function

Indicates low
battery volt­age

Lights up when the voltage
drops below the battery
accuracy guarantee voltage
(2.2±0.1 V)

REC•MEMO

Decimal point

Indicates Recording function

Indicates Continuity Check functio

Indicates Diode Check functio

Indicates Auto Powe

Save is enabl e

Frequency unit
Resistance and

continuity chec
units

Voltage and di
ode check unit

Current unit s
Indicates the

memory data

number
Bar-graph scale (42 dots)
Bar graph (with polarity indicator)

H.AUTO/REL RANGE

Changes to the func­tion indicated in blue

Toggles between AC
and DC modes(Cur­rent measurement)

(page 19)

Recording function
(Displays MAX/MIN/
AVG)*1

(page 32)

Voltage Detecting

(page 31)

Memory Function

(page 33)

Cancels the Auto
Power Save function
*2

(page 30)

HOLD AUTO function
(Holds the measured
value)

(page 25)

Turns the HOLD
function on/off

Turns the Relative
function (displaying
the relative value) on/
off*1

*1: Press the button for at least 1 second (REC

and REL require the button to be pressed
for a longer time).

*2: Turn on the power while pressing the but-

ton, and hold the button down until a beep
ing sound is generated (power-on option).

*2

(page 26)

(page 28)

Changes the manual
range and selects
range
Changes the auto
range from the manu
al range*1

Changes the input
level
(Frequency fun cti on )

Calls data from mem
ory*2

(page 18

(page 34

1.3 Parts Names and Functions

12

t

Function Selector

n

theses.

t

nt

( )

t

( )

t

( )

nt

10A

( )

nt

nt

(

)

nt

( )

nt

(Diode Check function)

Continuity function

Resistance function

DC voltage function

(Voltage detecting)

(Frequency

function)

AC voltage

function

Power OFF

Quick Reference

Indicates the function selector position

V

Indicates the terminal to which the red
test lead should be connected
Indicates the terminal to which the
black test lead should be conn ecte d

Press

REC•MEMO

when the
function in parentheses is being
used.

μA DC/AC current

40

function

μA DC/AC current

function

mA DC/AC curren

function
10A DC/AC

current function

Example

Switches betwee

REC•MEMO

( )

measurement to
display in paren-

Measurements Operations (page)

AC voltage
DC voltage

DC/AC Current
(40 μA)

DC/AC Current
(400/4000 μA)

DC/AC Current
(40/400 mA)

DC/AC Current
(10A)

Resistance
Continuity

V

V

40μA

μ

A

mA

Ω

REC•MEMO

REC•MEMO

REC•MEMO

REC•MEMO

REC•MEMO

Measuremen

Measureme

Measuremen

Measuremen

Measureme

Measureme

Measureme

Measureme

16
16

20

20

21

21
22
23

Diode

REC•MEMO

Measureme

24

13

1.3 Parts Names and Functions

V

e-

V

Bring test leads
c

r

line.

).

Example

V/ V/Ω/
4
10A

V/ V/Hz/Ω/

A/mA/10A

L

/

A/mA/10A

4
1

D
r

Frequency

Voltage
detecting

REC•MEMO

"Hz"

lights up

REC•MEMO

"1"

lights up

RANGE

( 1 - 4 )

×

2

RANGE

( 1 - 4 )

Measur
ment

lose to the powe

18

31

Quick Reference (application)

REC•MEMO

:Button

<1 second:
Press the button for at least 1 second.

Hold the measured value. (HOLD AUTO function)

This function is used when the displayed value cannot be checked during
measurement (such as when necessary to measure the conductor in a
dark place or using both hands.

REC•MEMO

: Turn on the power while pressing

the button (hold the button down
until a beeping sound is generated

0μA/μA/mA/

H.AUTO/REL

"HOLD"
Blinking

Move th e test lead s away from
the measurement object.

(Intermittent

sound)

25

Hold the measured value. (HOLD function)

//40μA/

H.AUTO/REL

Measure-

ment

H.AUTO/RE

26

μ

"O.F" is displayed to provide a warning

(Overflow Warning function)

V/ V/40μA

μ

When the measured value exceeds the maxi­mum value, "O.F" is displayed.

27

Use this function to check any disc repancy f rom t he r eference,
or to control the resistance for the purpose of zero adjustment

(Relative function)

V/ V/Ω/
0μA/μA/mA/
0A

isplay the

eference.

Cancellation: H.AUTO/REL (press again)

H.AUTO/REL

(<1 second)

("REL"

lights up)

28