Instruction Manual

PROFESSIONAL
Digital Hardness Tester for Metals (Rebound Type)

Model No.

LEEB HARDNESS TESTER

LHT-400

Thank you for purchasing the Niigata Seiki Leeb-Type Hardness Tester.
This digital instrument measures the hardness of (non-magnetized) metals: steel, cast steel, tool steel, stainless steel, heat
resistant steel, standard (gray) cast iron, ductile (nodular cast) iron, cast aluminum alloys, brass, bronze, and copper. Hardness ismeasured by impacting the surface of the sample with a test probe and measuring the rebound velocity.
●For safe and proper use of this product, please read this
instruction manual before use and follow the procedures
described. Please keep manual where it is accessible to user
for future reference.
●Keep this manual with the instrument if transferred or leased toa third party.
●For inquiries about this product, please contact dealer orNiigata Seiki at the address listed on the following page.

SAFETY NOTIFICATIONSIn this manual,
indicates RISK OF PERSONAL INJURY
OR PROPERTY DAMAGE if not followed. The
symbolindicates something which is PROHIBITED, and thesymbol indicates REQUIRED step or necessary condition.

■ PART IDENTIFICATION & FUNCTION[Main Unit]⑤ Cover⑥ Measure Button④ ＵＳＢ Port⑦ Handle③ LCD Display② Measuring
Ring⑩ Up Button⑨ Down Button① Probe⑧ Power Button[Accessories]⑪ USB Cable ·················· Connects for charging Main
Unit and transferring data.
⑫ Cleaning Brush ··········· For cleaning inside of MainUnit.
⑬ Measuring Ring (sml.) ··· Replaceable tip for use intight places.
⑭ ＡＣ Adapter⑭ AC Adapter ················· Charges Main Unit via the
USB Cable.
⑮ Calibration Block ········ Test Block of specified hardness
for checking, and calibrating
unit before each test.
● Storage Case ·············· Storage case for Main Unit
and accessories.
⑮ Calibration● Instruction Manual ······ This user guide.
Block⑪ ＵＳＢ Cable⑫ Cleaning
Brush⑬ Measuring Ring (sml.)● Case● Manual[Measurement Screen]Ⓛ ⒷⓀ

AUTO HLH HLD:
MAX: 419
M I N: 411
AVG: 414

Ⓐ
Ⓜ

Ⓒ

: 3 3
D ST&CAST
ST■Standard
Display

Ⓙ

0000
075%

Ⓘ Ⓗ

① Probe ·························· Impactor which strikes surface
during measurement.
② Measuring Ring ·········· Pressed to surface during
measurement.
③ LCD Display ··············· For display of measurements
and settings.
④ USB Port ···················· Connects to included USB cablefor charging and data output.
⑤ Cover ·························· Cover for USB Port. Pleasekeep closed when not in use.
⑥ Measure Button ··········· Press to release Probe andtrigger a measurement.
⑦ Handle ························· Move down to position Probefor measurement.
⑧ Power Button ·············· Power ON/OFF, and menu
select button.
⑨ Up Button ···················· Button to select a setting, andto control display size.
⑩ Down Button ················ Button to select a setting, andto delete last measurement.

Ⓓ
Ⓔ
Ⓕ
Ⓖ

ⒷⓀ Ⓒ

419

AUTO HLⒶ

H HLD:■Large Readout
DisplayⒶ Scaled t / AverageⒷ Scale UnitsⒸ MeasurementⒹ MaximumⒺ MinimumⒻ AverageⒼ Record NumberⒽ Battery Charge LevelⒾ No Measurements / TotalⒿ Material SettingⓀ High・Low Limit Exceeded（Ｈ） （Ｌ）Ⓛ Memory Auto / OffⓂ Probe Type

Press the Up Button
to toggle
between Standard and Large readout

SAFETY PRECAUTIONS

Please Observe

Always follow the procedures specified below in order to prevent harm to yourself or others, and to prevent damage to property.
■ Content marked as follows indicates risk of injury or
damage if not followed.

risk of personal injury or
WA R NING Indicatesproperty damage if not followed.

■ These symbols mark content that must be observed.
Denotes a prohibition– You MUST NOT do

Denotes a requirement –You MUST do

C AUT I ON
Read the manual and follow all instructions.

・Use of product other than as described in the manual may
cause accident.

Use only for measuring hardness.

・Use for any purpose other than measuring may damage orwear the instrument. Improper use may also cause accident.

Use in an environment which meets the following
conditions:● Keep away from direct sunlight● Keep in dry location protected from rain and water.
● Protected from use by children and unauthorized people.
・Use in location contrary to the above may cause poor accuracy,
damage to the product, or may result in accident or injury.

Handle With Care.

・Do not drop or subject to shock, do not place under heavy
objects. Damage may cause failure or poor accuracy.

Not for use on on materials which are easily fractured, or
which will be damaged by the dents created during tests.

・This instrument measures hardness by impacting a probe, witha hardness of HLD 1600, against the test surface. Please note:
after testing, some small dents will remain on workpiece.

Do not use on magnetized material or in presence ofmagnetic fields.

・Hardness is measured based on rebound speed of the Impact
Probe. If magnetic field is present, the rebound speed may beaffected and a precise measurement is not possible.

Do not dry­fire instrument.

・If test is performed without test surface under probe, theinstrument may be damaged and affect accuracy.

Do not Modify or disassemble beyond theprocedures described in this manual.

・It may damage product or affect accuracy. For service,please contact distributor or place of purchase.

Preparation of Test Surface

Accuracy Confirmation ・ Calibration

The workpiece and measured surface must meet the following
conditions.
① Mass: 5 kg or more

Instrument accuracy will be affected by shock or Probe wear.
Please check accuracy and calibrate before each use using
the supplied Calibration Block.

※For workpiece weighing between 2 and 5 kg, or for thin and easily
deformed parts, place on a surface plate or stable surface of morethan 5kg.
※For workpiece weighing less than 2kg, secure it to a surface plateof more than 5kg using a coupling agent, such as petroleum jelly,with a tight fit to stabilize.

① Confirm the hardness written on Calibration Block

The hardness of the calibration master is marked on the block
surface.

② Surface Roughness: Ra 2μm or less※If surface is rougher than Ra 2μm, please polish to meet
specification.

③ Radius of Curvature: greater than 30mm
④ Surface Temperature: 80°
C or less⑤ For testing surface hardness, a hardened surface thickness:
0.8mm or greater⑥ Not Magnetized※Be sure to demagnetize if there is any residual magnetism.

⑦ Bare (unpainted) Surface※ If sample is painted, remove any paint or coating before test.

⑧ Not easily fractured, or damaged by the surface indents
resulting from the test

※This instrument measures hardness by impacting a probe, with ahardness of HLD 1600, against the test surface. Please note: after
testing, some small dents will remain on workpiece.

Charging① Connect with the provided USB Cable

Connect to the AC Adapter using the included USB cable.

② Plug in the AC adapter

Plug the AC adapter into the power mains (100V AC).

⑮ Calibration Block

Block hardness② Measure the Calibration Block hardness

Use the "Hardness Test Procedure" on the following page to test
the hardness.
● Material = Steel● Unit = HL ● No. of Measurements = 5※Make sure the Calibration Block surface is clean before measurements.
※Take the measurements in a spot free of marks from previous
measurements.

③ Error Correction※If the measured hardness from step ② is within ±17HL of thehardness from step ①, then the accuracy is confirmed within theguaranteed range and the instrument is ready to use.

※If the measured hardness from step ② is NOT within ±17HL of thehardness from step ①, then the calibration must be adjusted. Enterthe measurement error In the "Setup Menu" → "6. Calibration" asshown in the following page.

④ USB Port

⑭ AC Adapter

Connect

The Main Unit contains a rechargeable battery. Whenpower level drops below 20%, please charge as follows.

779HLD

Main Unit
⑪ USB
Cable

C

t

ec

n
on

USB PortPower ON／OFF
The power will turn on and the Measurement Screen will display on the LCD.
● Power ON ··········· Press the Power Button.
● Power OFF ········ From the Measurement Screen, press and hold the Power Button
for 3 seconds. Power and LCD will turn off.

Hardness Test Procedure※Because workpiece hardness my not be uniform, measurements should betaken from multiple locations on the surface of the workpiece for averaging.

③Press the Measuring Ring against the surface.

Make sure the workpiece and test spot meet the conditions listed in the section"Preparation of Test Surface", and press the Measuring Ring onto the surface.
※ Make sure there are no scratches or marks from previous measurements.

⑦ Handle④ Push down on the Handle, and then pull it back up. (Figure 1)

Workpiece

Push down on the Handle to charge the internal probe for the test,
then lift the Handle to bring it into position for the test.
※Make sure you hold the Handle secure while bringing it up to thetop. If the Handle slips, it may return with a shock and cause
damage.

⑤Press the Measure Button. (Figure 2)

With the Measuring Ring held firm to the surface, press the Measure
Button. The Probe will release and impact the surface. Hardness will
be calculated from the rebound velocity.
※Be careful not to push down on the Handle when pressing the
Measure Button, it will cause inaccurate readings.

⑥ Repeat the measurement in steps ④~⑤ .

Average
Value

Maximum

HLD:
MAX: 419
M I N: 411
AVG: 414: 3 3
D ST&CAST
ST

0000
075%

Minimum
Average（Fig.３）【Automatic Angle Compensation】 Workpiecere

The instrument automaticallysenses the measurement angle
and applies a correction factor to
the reading. Measurement canbe made freely over 360° range.
Please
make
sure
the
Measuring Ring is always
pressed firm against the surface
when taking a measurement.

su

The average value, maximum reading, and minimum reading aredisplayed on the LCD display.

AUTO HL（Fig.２）ea⑦ The measurements are displayed. (Figure 3)（Fig.１）

M

Repeat the required number of times specified in the "Setup
Menu"→ "2. Average" for calculating an averaged reading.

⑥ Measure
ButtonReturn to top

Specify the workpiece material and desired scale units in the "Setup Menu"→ "3. Material & Scale" After entering the settings, select "1.
Measurement" to return to the Measurement Screen.

Push down② Set the material and measurement units.

Press

to turn on the power.

２

Press the Power Button

１①Turn the power ON.

３

Follow the steps below for a basic hardness test.

② Measuring
Ring

Setup Menu
When power is ON, pressing the Power Button
will display the Setup Menu screen. Within the Setup Menu, the Up and Down
buttons
are used to select items and to change values, and the power button
is used to enter the selection.

1. Measurement ····· Return to the Measurement Screen.
2.

Average ······· Change the number of measurements averaged for each reading. You can select 2-8 measurements.

3. Material & Scale ··· Specify the workpiece material, and set the measurement units. Back Page: Meas. Range Listing for Each Material, Units
When specifying the material and units, options are shown, so select as required.

4. Tolerance ········ To set up tolerance function. Press Up Button

to change the value, and Down Button"H" or "L" will appear on the display for readings above or below the set limits.

to move to next digit.

5. Memory ········· Control the storage of measured data.

1. Memory on/off ······ ON - Measurements saved sequentially up to number specified below.
OFF - Measurement data is not saved
2. File Setting ··········· Specify the storage destination for the group of measurements.
Ten groups, A to J, can be stored with 200 Measurement averages each.
3. Delete Single ······· Delete data from the specified group.
4. Delete All ············· Clear the Main Unit stored measurement data.

6. Calibration ······· Correct the measurement by entering the error value determined in the accuracy check from the "Calibration" section
on the previous page.

7. Auto Shutdown ···· Automatic power shut off can be selected for 1, 2, 5 minutes; or disabled.
8. Contrast ········· Adjust the contrast of the display.
9. Impact Type ······ Set parameters to match the type of probe Back Page: Installing DL-Type Probe (sold separately)
10. Language ······· Select from Japanese / English.
11. Default ········· Restore all settings to factory default.

Measurement Data Output① Connect the Main Unit to the computer

Computer USB Port

Please connect the USB Port of the Main Unit to the computer's USB Port using the
USB Cable and turn on the power. The Display will show "Connected between
instrument and PC"and the computer will show a CD drive icon.

Co② Open the CD drive icon on the computer.

File Number
Probe type: D/DL
The material type set in the "Material & Scale" setting
The scale set in the "Material & Scale" setting
Average of Measurements
Measurement data. The number will correspond to the "ectConnect

The data is stored as text (.txt) files labeled A∼J, and you can open the desired file toview.
The file contents are listed below
Num
ImpactMaterial
Scale
AVG­DATADATA1～8⑪ USB Cablenn④ USB Port

Main
Unit
Connected between
instrument and PC

Average" setting※ Files can not be deleted or created through the computer, you must delete at the Main Unit.

Changing The Measuring Ring, Cleaning※ Before cleaning, or replacing the Measuring Ring,
make sure the power is turned OFF.

The Measuring Ring can be exchanged with a small one if required to fit in tight locations.
Also, the ring can be removed to for periodic cleaning inside of the mechanism.

Loosen① Press the Measure Button.

Release the probe from charged position.

② Turn the Measuring Ring to remove it from the Main Unit (Figure 4) and take out the Probe.

② Measuring
Ring③ Cleaning.

Using the supplied brush, clean the inside of the main unit as well as the Probe toremove any dust or dirt.

④ Replace the Probe and reattach the Measuring Ring to the Main Unit.

② Measuring Ring

Insert the Probe in the direction shown in the drawing. (Figure 5)Screw the Measuring
Ring back on to the main body.

Installing DL-Type Probe (sold separately)
Measurement can be made in narrow spaces, such as the bottom groove of a large
gear, by replacing the Probe with the DL-type Probe available for the Hardness Tester.

Threads

Tighten（Fig.４）（Fig.５）① Press the Measure Button.

Insert① ProbeMeasurement guide

Release the Probe from charged position.

② Turn the Measuring Ring to remove it from the Main Unit (Figure 4)
and take out the (D­type) Probe.
③ Insert the DL­type Probe as shown in the drawing and attach themeasurement guide. (Figure 6)（Fig.６）④ Change "Setup Menu → "9. Impact Type" from "D" to "DL".

DL-Type Probe

InsertMeasurement Range Listing by Material, Units / Specifications

Unit Scale
Material
1. ST& CAST ST.
2. CWT STEEL
3. STAINLESS ST.
4. G CAST IRON
5. N CAST IRON
6. CAST ALUM
7. BRASS
8. BRONZES
9. COPPER

HL

300 〜 900
300 〜 640
300 〜 800
360 〜 650
400 〜 660
174 〜 560
200 〜 550
300 〜 700
200 〜 690

● Accuracy: within ±17HL● Operating Temperature: 0∼+40°C

HRC

20.0 〜 68.0
20.4 〜 67.1
19.6 〜 62.4
−
−
−
−
−
−

HRB

38.4 〜 99.5−
46.5 〜 100.7−−−
13.5 〜 95.3−−

HB

80 〜 647−
85 〜 656
90 〜 334
131 〜 367
20 〜 190
40 〜 173
60 〜 290
45 〜 315● Weight: Main unit… 97g● Data Storage Capacity: Max. 2,000 avg. readings

HS80 〜 940
80 〜 898
85 〜 802
−
−
−
−
−
−

σb

373 〜 2008
−
−
−
−
−
−
−
−

● Auto Power Off: 1, 2, 5 minutes, or disabled● Charge time: approx. 3 hours

Maintenance and Storage
Remove any dust or grime with a dry cloth.

Any contamination entering inside the Main Unit will prevent smooth operation of the Probe.

Store in a cool, dry, and dark location in the provided case.

HV

32.5 〜 99.5
−
−
−
−
−
−
−
−

Keep out of direct sunlight and moisture, and please keep secure from unauthorized personnel.

Niigata
Co.,Ltd.
Ltd.
Niigata seiki
Seiki Co.,
5-3-14, Tsukanome, Sanjo, Niigata, Japan, 955-0055

6­15­22,
Sanjo, Niigata,955­0055
Tel.Tsukanome,: +81-256-33-5522
Fax. : Japan+81-256-33-5518
TEL:
+81­
256­31­5670 FAX: +81­256­39­7730
MAIL
intl.sales@niigataseiki.co.jp

MA I LURL: i n t l http://www.niigataseiki.co.jp. s a l e s@n i i ga t a s e i k i . c o . j p
URL http://www.niigataseiki.co.jp

I336-K

1812