DMQ QH5 Series User manual

P/N: QHD501 –ENG –Rev 4 –2020

I
Chapter 1
First steps
1.1
Know the QH5
1
1.1.1
Front panel
2
1.1.2
Connectors
2
1.2
Install or replace batteries
3
1.3
Connecting the impact device
5
1.4
Using the impact device
6
1.4.1
Loading the impact body
6
1.4.2
Release and measure
6
1.5
The “Q” key
7
1.6
Display illumination and contrast
7
1.6.1
Display backlight illumination
7
1.6.2
Display contrast
8
1.7
Locking and unlocking the keypad
8
Chapter 2
Measuring with the QH5
2.1
Numerical measure screen (Normal)
10
2.1.1
Screen mode-1 (Datalogger)
10
2.1.2
Screen mode-2 (Material)
11
2.1.3
Screen mode-3 (Statistics)
11
2.2
Keys in numerical measure modes
12
2.3
Graphic measure screen (Histogram)
14
2.4
Keys in the graphic measure screen mode
15
2.5
Set impact device angle
16
2.6
Select material and hardness unit
17
Chapter 3
Menu system and editing
3.1
Instructions on using the menu system
19
3.1.1
Text editor
20
3.2
Main menu
22
3.2.1
Change hardness unit
22

II
3.2.2
Alarm settings
23
3.2.3
Set histogram range
24
3.2.4
Select language
24
3.2.5
Unit information
25
3.3
General configuration options
25
3.3.1
Set time and date
26
3.3.2
Set time and date format
26
3.3.3
Set keypad sensitivity
26
3.3.4
Set auto-off time
28
3.3.5
Adjust display contrast
28
3.3.6
Beep activation
29
3.3.7
Introduction screen
29
3.3.8
Owner information
29
3.3.9
Lock configuration options
31
3.3.10
Model upgrade licenses
32
3.3.11
Return to factory default settings
33
3.4
Measuring configuration options (Hardness)
34
3.4.1
Set impact device angle
34
3.4.2
Select material
35
3.4.3
The “Plus” key
35
3.4.4
Set group (N) number
36
3.4.5
Select measure mode
37
3.4.6
Create custom or user units
37
3.4.7
Select impact device type
41
3.4.8
Set alarm for impact device tip
42
3.4.9
Return to factory default settings
42

III
Chapter 4
Using the Datalogger
4.1
How data is organized
43
4.2
Memory menu
44
4.3
Creating a file
44
4.4
Actions over single files
45
4.4.1
View data in a single file
46
4.4.2
The “Q”key in a grid
47
4.4.3
The “Q”key in a histogram
48
4.4.2
Send data from a single file
48
4.4.3
Rename a file
49
4.4.4
View file size
49
4.5
Actions over all files
49
4.5.1
Send all files
49
4.5.2
Erase all files
49
4.6
Quick memory menu (Mem key)
50
4.7
Connecting to PC with DataCenter
51
4.8
Datalogger configuration
52
4.8.1
Configure communications
52
4.8.2
Capture modes
54
4.8.3
Advanced configuration
54
Tips on how to measure correctly
Technical specifications
Additional information
Unit maintenance
QH5 accessories
Error messages
Proper disposal
Our website: www.demeq.com
Technical Support

IV
And thank you for purchasing a QH5 rebound hardness tester.
At dmq we develop, manufacture and distribute software and quality
control instruments offering innovation and solutions that come as a
direct result of listening to your needs as a user. We apply some of
the latest technology available in the industry to build instruments
that are robust, precise and easy to operate.
We are convinced that our products would not be complete without
permanent technical and after sales support. So in addition to a great
product we offer:
Quick answers to your inquiries.
Unlimited access to technical information as well as
application notes.
Special offers for registered customers.
Firmware and software upgrades at no charge.
Attention to your inquiries and suggestions.
We hope that the QH5 will meet and exceed your application needs.

Chapter 1 1
The information included in this manual applies to QH5 series
portable hardness testers including models D, G and M.
dmq is a registered trademark of demeq S.R.L and its affiliate
companies.
The information contained in this manual is intended to educate
users on the operation of the QH5 impact hardness testers. Failure to
read and understand this manual can lead to measurement errors.
Decisions based on measurements and or results that are erroneous
can lead to property damage, personal injury or even death. Demeq
S.R.L assumes no responsibility as a result of the improper use of our
instruments.
ASTM A956
Correct use of an impact hardness tester requires that you take all of
the following into consideration:
Select the instrument as well as the impact device that is
best suited for your application.
Know the specific requirements for the test you will be
conducting.
Make sure that the person operating the unit has been
trained on its use.

2 Chapter 1
This manual provides all of the information needed to configure and
operate the QH5 hardness tester. However there are additional
factors that can affect tests done with this instrument. Specific
information on those factors is outside the scope of this manual.
When in doubt you should always seek expert advice or refer to
specific textbooks on portable hardness testing. Additional
information can also be found on the internet and through local
government agencies as well as in technical institutes.
QH5 D, G and M models operate on the Leeb impact rebound
method where the ratio between the impact and rebound velocities
that is released on the test piece is measured to establish a Leeb
hardness value. The step by step process is represented in figure 1 as
follows: 1, the impact body is released and travels inside the impact
device; 2, the impact body tip hits the test piece; 3, the impact
produces a rebound.
Figure 1: Representation of the Leeb rebound method

Chapter 1 3
The measured Leeb value (HL) represents a direct hardness value that
is automatically converted to other hardness units of your choice such
as Brinell, Vickers, Rockwell and Shore. Both the HL value and another
selected hardness unit are displayed on the unit screen
simultaneously.
We offer 6 (six) impact devices being that each one of them is
different and ideal for specific applications. In this section we offer
general information including measuring ranges and recommended
applications for each impact device type.
Please see figure 2 below for a representation of the physical aspect
of each one of the impact devices that we offer.
Figure 2: Available impact device types for QH5 units

4 Chapter 1
Impact device type D
This is a “universal” type impact device because it covers the widest
range of hardness units, hardness ranges and materials available on
QH5 hardness tester which also means that you will cover the widest
range of applications.
Impact device type DC
The only difference between a type DC and a type D impact device is
that the body on a DC impact device is 86mm long or half the length
of a type D impact device making it ideal for measurements in hard
to reach places. Unlike all other impact devices that are spring loaded
type DC impact devices are loaded manually.
Impact device type DL
The long and thin “needle type” tip allows DL impact devices to work
in very narrow areas that cannot be measured with any other impact
device. This impact device is commonly used to measure hardness in
gears.
Impact device type C
Type C impact devices produce the least amount of energy when
compared to all other impact devices (up to 25% less than device
type D) making it the best choice for measuring superficial hardness
and small parts. The lowest impact energy also means the smallest
indentation.
Impact device type G
Type G impact devices use a ball that is 5mm in diameter and it also
releases the highest impact energy at 90 N*mm allowing it to be
used over rough surface finishes such as those found in metal casts.

Chapter 1 5
Impact device type E
While type D impact device measure up to 940HV (Vickers), type E
impact devices use a synthetic diamond ball that allows for
measurements in hardened or template steel up to 1211HV.
The table below shows detailed technical information on each impact
device type.
Parameter (Unit)
Impact device type
D
DC
DL
C
G
E
General characteristics
Length (mm)
147
86
202
141
254
155
Diameter (mm)
20
20
20
20
20
20
Weight (g)
75
50
100
75
250
80
Max Hardness (HV)
940
940
950
1000
650
1200
Impact device tip (ball)
Diameter (mm)
3
3
2.78
3
5
3
Hardness (HV)
1600
5000
Material
Tungsten carbide
Diamond

6 Chapter 1
Impact body
Energy (N*mm)
11
11
11
3
90
11
Mass (g)
5.5
5.5
7.3
3
20
5.5
Surface test piece requirements
Rugosity ISO
N7
N7
N7
N5
N9
N7
Rugos. RT (µm)
10
10
10
2.5
30
10
Rugos. RA (µm)
2
2
2
0.4
7
2
Minimum test piece weight (Kg)
Stand alone
5
5
5
1.5
15
5
With solid support
2
2
2
0.5
5
2
Coupled with
paste
0.1
0.1
0.1
0.02
0.5
0.1
Minimum test piece thickness (mm)
Coupled
3
3
3
1
10
3
Surface thickness
0.8
0.8
0.8
0.2
—
0.8
Test piece impact indentation
On parts up to 300HV
Diameter (mm)
0.54
0.38
1.03
0.54
Depth (µm)
24
12
53
24
On parts up to 600HV
Diameter (mm)
0.45
0.32
0.90
0.45
Depth (µm)
17
8
41
17
On parts up to 900HV
Diameter (mm)
0.35
0.30
—
0.35
Depth (µm)
10
7
—
10

Chapter 1 7
This section provides an overview of basic impact device components.
Figure 3: Impact device components
Figure 3 shows the most important parts that make up an impact
device and the procedure used to remove the impact device body.
Over time and depending on the number of measurements that you
make the impact tip (ball) located on the impact device body will
need to be replaced. In order to remove the impact body turn the
support ring clockwise (see figure 3-1) until the ring is released and
the impact body falls off (figure 3-2). When doing this make sure that
you are working on a table where the impact body can fall and not
get damaged if hitting the floor. Remove and replace the impact tip
(ball) making sure that everything is left clean and repeat the
procedure to put the impact body back in place.

8 Chapter 1
All QH5 series portable hardness testers are for industrial use only
and cannot be used in medical applications. The QH5 operates on
two AA size batteries. We strongly recommend that you use only top
brand name alkaline batteries.
Disposal of your QH5 and its components must be done in
compliance with all applicable regulations.
Because of its complexity level, software is never really completely
error free. For this reason in software controlled instruments always
make sure that the operations required for your application are in
correct working order.
Demeq provides a 3 year limited warranty on electronic units that is
automatically extended to 5 years when you register your unit while a
6 (six) month warranty is offered on impact devices.
Please remember to register your unit at:
http://www.demeq.com
Every instrument undergoes thorough testing during manufacturing
as well as before shipping. In the event warranty service becomes
necessary Demeq and or your local distributor will make every
reasonable effort to get your problem resolved in the earliest possible
time and when available will offer you a loaner unit while your
instrument undergoes repair.

Chapter 1 9
Figure 1.1: Front of the unit
1. Graphic LCD display with LED backlight illumination
2. Move Left key / View partial statistics (Stat)
3. Move Up key / Manually store a value (Store)
4. Move Right key / Switch to graphical measure mode screen
(Graph)
5. Menu key / Enter and exit measure screen / Exit and return
to menus (Home)

10 Chapter 1
6. Move Down key / Quick access to memory menu screen
options (Mem)
7. Change backlight illumination key (On, Off, Auto)
8. Enter key / Edit values on the measure screen (Edit)
9. The key: Power On and Shutdown (touch and hold for 2
seconds) / Make quick and short touches to activate special
features
10. The key: Direct measure screen access from any menu
screens / User selectable functions
11. Horizontal scrolling center point (lock and unlock keypad
on measure screen)
12. Vertical scrolling center point (adjust LCD contrast)
Figure 1.2: Unit connectors
1. Impact device connector type Lemo 0B
2. USB mini connector to connect to PC using a USB cable

Chapter 1 11
The QH5 is powered by 2 (two) AA batteries that are placed in the
battery compartment located in the back of the unit. To gain access
to the battery compartment slide the cover as shown in figure 1.3-1
and gently push the extraction ribbon upward and slightly towards
the right to release the batteries (figure 1.3-2).
When you install new batteries, first insert the positive end of each
battery so that it coincides with the positive pole inside the battery
compartment as you see in figure 1.4-1.
Always leave the extraction ribbon underneath the batteries.
Figure 1.3: Removing batteries

12 Chapter 1
Figure 1.4: Replace / Insert batteries
Notes
Always use new alkaline top brand batteries for
extended battery life.
Do not mix new and old batteries. Always replace both
batteries.
Rechargeable batteries type NiMH can be used but will
result in less time of continuous operation.

Chapter 1 13
Important
Do not remove batteries while the unit is powered as
this may affect the Datalogger (See Appendix:
“Additional information, Error Messages”)
The QH5 uses a type Lemo 0B 3-pin connector located on top of the
unit. All dmq impact devices are provided with Cal-Tag technology
allowing you to easily switch or replace impact devices with no need
to calibrate the unit. Universal non-brand impact devices can also be
used as long as they have the same connector, but dmq does not
guarantee their performance.
To connect the impact device simply
align the red dot on the male
connector with the red dot on the
female connector located on the unit
and press gently until connected (see
figure 1.5)
To release the impact device hold the
knurled section on the male
connector and gently pull out.
Never remove the connector using
the cable.
Figure 1.5: Connecting the impact device

14 Chapter 1
The procedure explained herein is applicable to all impact device
types except for impact device type DC as it does not use a spring
loading mechanism.
Place the impact device over the surface you want to measure and
load by gently pushing the moving body of the impact device in the
same direction as the test piece surface. Push the moving body until
you reach the bottom limit and then bring the body back to its initial
position.
The impact device is now loaded and ready to be used.
Once the impact device has been loaded use one hand to firmly hold
the bottom of the impact device (the part that touches the surface
you want to measure) against the surface and use your other hand to
press the release button located on top of the impact device.
After pressing the button, the impact body will hit the test piece
surface and a hardness value will be displayed within a few seconds.
Repeat this same procedure for each measurement.
Important
The Leeb method for hardness testing has requirements
and limitations that must be considered in order to
obtain reliable and accurate measurements (See
Appendix: “Tips on how to measure correctly”)