KERN HFD User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Service Manual
Electronic Crane Scales
KERN HFD
Version 1.0
02/2018
GB
HFD-SH-e-1810

HFD-SH-e-1810 2
GB
KERN HFT
Electronic Crane Scales
Version 1.0 03/2018
Service manual
Content
1Basic Information .....................................................................................................4
2Introdution.................................................................................................................4
3General Safety Instructions.....................................................................................5
3.1 Organizational measures................................................................................................................. 5
3.2 Environmental conditions ............................................................................................................... 5
3.3 Proper use......................................................................................................................................... 5
3.4 Improper Use..................................................................................................................................... 6
3.5 Warranty ............................................................................................................................................ 6
3.6 Safe working ..................................................................................................................................... 6
3.7 Monitoring of Test Resources......................................................................................................... 6
3.8 Testing upon acceptance ................................................................................................................ 7
3.9Initial Commissioning ...................................................................................................................... 7
3.10 Shutdown and storage..................................................................................................................... 7
5The crane scales at a glance ...................................................................................8
5.1 Overview............................................................................................................................................ 8
5.2 Operating elements.......................................................................................................................... 9
5.3 Overview of display:......................................................................................................................... 9
5.4 Keyboard overview:.......................................................................................................................... 9
5.5 Radio remote control...................................................................................................................... 10
5.6 Label ................................................................................................................................................ 10
6Commissioning.......................................................................................................11
6.1 Unpacking ....................................................................................................................................... 11
6.2 Checking the original dimensions................................................................................................ 12
6.3 Rechargeable battery operation.................................................................................................... 12
6.4 Suspending the balance ................................................................................................................ 13
6.5 Condition......................................................................................................................................... 13
7Operation.................................................................................................................14
7.1 Safety instructions ......................................................................................................................... 14
7.2 Loading the crane scales............................................................................................................... 15
7.3 Loading the balance....................................................................................................................... 15
8Menu........................................................................................................................18
8.1 Navigation in the menu:................................................................................................................. 18
8.2 Overview:......................................................................................................................................... 19
8.3 Check overload records................................................................................................................. 20
9Adjustment..............................................................................................................21
10 General.................................................................................................................22
10.1 Cleaning........................................................................................................................................... 22
10.2 Determine the Problem .................................................................................................................. 22
10.3 Testing Load cell............................................................................................................................. 23

3 HFD-SH-e-1810
10.4 ElectricalTest:................................................................................................................................. 23
10.5 Testing PCB Voltages ..................................................................................................................... 24
10.6 AC Power......................................................................................................................................... 24
10.7 Adaptor Voltage .............................................................................................................................. 24
10.8 PCB Input Voltage........................................................................................................................... 24
10.9 Check Battery Voltage and Charging Voltage.............................................................................. 24
10.10 Replace Main Board ................................................................................................................... 25
10.11Battery Replacement.................................................................................................................. 26
11 Trouble Shooting.................................................................................................27
12 Error messages...................................................................................................28
13 Drawing................................................................................................................30
14 Circuit Diagram....................................................................................................32
14.1 AD..................................................................................................................................................... 32
14.2 COM.................................................................................................................................................. 32
14.3 DIS.................................................................................................................................................... 33
14.4 MCU.................................................................................................................................................. 34
14.5 POWER ............................................................................................................................................ 34
15 Maintenance, Repair, Cleaning and Disposal...................................................35
15.1 Cleaning and Disposal................................................................................................................... 35
15.2 Regular maintenance and care ..................................................................................................... 35
15.3 Regular maintenance: .................................................................................................................... 37

HFD-SH-e-1810 4
1 Basic Information
The device must be repaired only by trained specialist staff or personnel with professional
formation (such as a repair-specialist accredited by law concerning verification). The service
manual is obligatory for repair work. After repair, original conditions of the device have to be
restored. Only original spare parts should be used.
Instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval. A violation of this
specification will result in a loss of the type approval! After successful repair the balance will have
to be reverified before it can be used again in a statutorily regulated field.
Detailed instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval. A violation of this
specification will result in a loss of the type approval!
After successful repair the balance will have to be reverified before it can be used again in a
statutorily regulated field.
2 Introdution
This service manual covers the HFD series and is edited for the authorized servicing personnel.
Note all rights are reserved. Copying any part of this manual is prohibited without our permission.
In this lineup it is an eco product, Therefore, it is not intended to represent the repair manual in
detail, since the construction of the balance is very simple. It is therefore only referring to the list
of related to disposal spare parts.

5 HFD-SH-e-1810
3 General Safety Instructions
Duties of the owner-operator
Follow national accident prevention regulations and all operator health and safety at work and
operating regulations.
Observe all safety regulations of the crane manufacturer.
The balance may only be used for the proposed purpose.Any type of use which is not
specified in these operating instructions, will be considered as improper use.The customer is
solely responsible for material damage and injury of persons resulting from an improper use,
Messrs. KERN & Sohn will not be liable under any circumstance.
Messrs . KERN & Sohn cannot be held liable, if the crane scales are modified or used
improperly and if damage is resulting from such use.
Inspect and service crane balance, crane and load suspension devices regularly (see chap.
10.3 in the HFD user manual).
Log the test result and keep it in the logbook.
3.1 Organizational measures
Only trained and instructed staff may operate the balance.
Make sure that the operating instructions are kept nearby the operation site of the crane
scales.
Assembly, commissioning and maintenance should only be carried out by trained specialists.
Repair of safety-relevant pieces may only be carried out by KERN or by service partners
authorized by Messrs. KERN.(Competence certificate or training).
Use original spare parts only.
All repairs and spare parts must be documented by the service partner (see list, chap. 11.2 in
the HFD user manual).
All maintenance must be documented (see checklist chap. 11.1 in the HFD user manual).
Load suspending components may only be exchanged as a complete spare parts set. The
dimensions of the new components must be noted (see checklist chapter 11.1 in the HFD
user manual).
3.2 Environmental conditions
Never operate the crane scales in explosive environment. The serial version is not explosion
protected.
Operate the crane scales only under environmental conditions as specified in these operating
instructions (especially in chapter 1 „Technical data“in the HFD user manual).
Do not expose the crane scales to strong humidity. Non-permitted condensation
(condensation of air humidity on the appliance) may occur if a cold appliance is taken to a
considerably warmer environment. In this case, acclimatize the disconnected appliance for
ca. 2 hours at room temperature.
Do not operate the crane scales in corrosive environment.
Protect the crane scales against high humidity, vapours and dust.
Major display deviations (incorrect weighing results) may be experienced should
electromagnetic fields (e.g. due to mobile phones or radio equipment), static electricity
accumulations or instable power supply occur. Change location or remove source of
interference.
3.3 Proper use
The balance you purchased is intended to determine the weighing value of material to be weighed.
It is intended to be used as a “non-automatic“ balance, i.e. the material to be weighed is suspended

HFD-SH-e-1810 6
on the crane hook only vertically, manually, carefully and without jerks. As soon as a stable
weighing value is reached the weighing value can be read.
Use the crane scales only for lifting and weighing of freely movable loads.
Danger of injury due to improper use. Not allowed are e.g.:
Exceeding the allowed nominal load of crane, crane scales or any type of load
attachment devices
Conveying persons,
Pulling loads over an inclined surface,
Tearing-off, pulling or towing loads.
Modifications or reconstructions of the crane scales or of the crane are not allowed.
3.4 Improper Use
Do not use balance for dynamic weighing. In the event that small quantities are removed or added
to the material to be weighed, incorrect weighing results can be displayed due to the “stability
compensation“. (Example: Slowly draining fluids from a container suspended on the balance.) Do
not leave permanent load suspended on the balance. This may damage the measuring system as
well as safety-relevant parts.
The balance may only be used according to the described conditions. Other areas of use must
be released by KERN in writing.
3.5 Warranty
Warranty claims shall be voided in case
Our conditions in the operation manual are ignored
The appliance is used outside the described uses
The appliance is modified or opened
Mechanical damage and damage caused by media, liquids,
Natural wear and tear
The appliance is improperly set up or incorrectly electrically connected
The measuring system is overloaded
3.6 Safe working
Do not stand underneath suspended loads!
Position the crane in a way that the load is lifted vertically.
When working with the crane and crane scales wear personal safety equipment (helmet,
safety shoes etc.).
3.7 Monitoring of Test Resources
In the framework of quality assurance the measuring-related properties of the balance and, if
applicable, the testing weight, must be checked regularly. The responsible user must define a
suitable interval as well as type and scope of this test. Information is available on KERN’s home
page (www.kern-sohn.com with regard to the monitoring of balance test substances and the test
weights required for this. In KERN’s accredited DKD calibration laboratory test weights and
balances may be calibrated (return to the national standard) fast and at moderate cost.

7 HFD-SH-e-1810
3.8 Testing upon acceptance
When receiving the appliance, please check packaging immediately, and the appliance itself when
unpacking for possible visible damage.
3.9 Initial Commissioning
In order to obtain exact results with the electronic balances, your balance must have reached the
operating temperature (see warming up time chap. 1 see the HFD User manual).
During this warming up time the balance must be connected to the power supply (mains,
accumulator or battery).
The accuracy of the balance depends on the local acceleration of gravity.
Strictly observe hints in chapter Adjustment.
For checking original dimensions, s. chap. 6.2 in the HFD user manual
3.10 Shutdown and storage
Take off the crane scales from the crane and dismantle all load attachment devices from the
crane scales.
Do not store the crane scales at open air

HFD-SH-e-1810 8
5 The crane scales at a glance
The crane scales are a multi-purpose and cost-saving solution for overhead weighing
applications such as e.g. recycling, metal processing, machine engineering, transport and
logistics.
With the radio remote control, operation will be more comfortable yet.
5.1 Overview
Fig.1: Front view of balance
Fig.2: Radio remote control
(similarillustration)
1
Uppershackle
5
Antenna
2
Display
6
Keyboard
3
Keyboard
4
Lowershackle
5
6

9 HFD-SH-e-1810
5.2 Operating elements
5.3 Overview of display:
[] over the symbol appears if
the rechargeable battery is being charged
the capacity of the rechargeable battery is exhausted
HOLD
the data-hold function is active
NET
the scales have been tared
the weight display is stable
a
the weight is in the area around the zero point
5.4 Keyboard overview:
Button
Description of function
HOLD
Record weight value (freeze)
Shift decimal point (adjustment mode)
M+
Totalization
Number selection to the right
Exit menu
TARE
Taring
a
Zeroing
ON/OFF
Turn on or off the balance

HFD-SH-e-1810 10
5.5 Radio remote control
The balance can be operated by the radio remote control like by a keyboard. All functions
(excepted ON/OFF) can be selected.
The red LED must light up when any button is pressed. If it does not light up, the batteries in the
remote control must be exchanged.
Range on free surface (free of buildings) approx. 20 m.
5.6 Label
Do not stand or go under suspended loads.
Do not use on building site.
Keep an eye on suspended loads.
(example)
Do not exceed nominal load of crane scales.
The product conforms to the requirements of the German
Equipment and Product Safety Act.