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.

11 HFD-SH-e-1810
6 Commissioning
Attention: Always observe chapter Fehler! Verweisquelle konnte nicht gefunden werden. "General
Safety Instructions"! of the HFD user manual
6.1 Unpacking
SAFETY
INSTRUCTIONS
for protection against
break
Once delivered and unpacked, crane scales will not be taken
back.
The crane scales have been sealed by Messrs. KERN.
Load suspension devices are sealed by an adhesive tape.
The packaging is also sealed by adhesive tape.
+Broken seal obliges to purchase.
Thanks for your comprehension.
Your KERN Quality assurance team
CAUTION
Danger for the back!
The crane scales are compact and quite heavy.
Remove the scales from packaging only with the help of a
second person.
Use a lifting device such as a crane or a forklift truck.
Secure the scales that they cannot fall down when they are
lifted.
Only use original packaging for returning.
Make sure that all parts are completely present.
Crane scales
Mains adapter
Remote control
Operating instructions (logbook)

HFD-SH-e-1810 12
6.2 Checking the original dimensions
Enter the original dimensions shown on the production data sheet in the grey fields of the
checklist chap. Fehler! Verweisquelle konnte nicht gefunden werden.. in the HFD user manual
Check original dimensions of crane balance; for implementation see chap.15.2 "Regular
Maintenance" in the HFD user manual
Enter all data (date, tester, results) in the first line under "Inspection before first use" in the
checklist (see chapter Fehler! Verweisquelle konnte nicht gefunden werden. in the HFD user
manual)
CAUTION
If the dimensions of your first safety inspection do not match those of
KERN, the balance must not be put into operation. In this case please
contact a service partner authorised by Messrs. KERN.
6.3 Rechargeable battery operation
CAUTION
Material damage on crane scales
Only use the delivered mains adapter.
Make sure that the mains adapter, the cable and the mains
plug are in a perfect condition.
Do not use the crane scales during the loading process.
Before the first use, the rechargeable battery should be charged by connecting it to the mains
power cable for at least 24 hours. The operating time of the rechargeable battery is approx. 60
hours.
The capacity of the rechargeable battery will soon be exhausted, when the display begins to flicker. If
"lo_bat" appears, the balance will remain operable for approx. 30 minutes more, then it switches
off automatically. Connect the power cable as soon as possible to load the rechargeable battery.
The LED display over provides information about the battery's charging status.
red:
Voltage has dropped below prescribed minimum.
green:
Rechargeable battery completely reloaded
yellow:
Charging storage battery
To save the battery, the balance switches automatically off without weighing (time can be
selected, see chap. Fehler! Verweisquelle konnte nicht gefunden werden.. Function "F9 of" in
the HFD user manual)
When the crane scales are out of operation for a longer period, remove the rechargeable battery.

13 HFD-SH-e-1810

HFD-SH-e-1810 14
6.4 Suspending the balance
6.5 Condition
The crane needs a safety bracket (1) that the unloaded crane scales cannot fall down.
If the safety bracket is missing or damaged, please contact the crane manufacturer in order to
receive a hook with this safety equipment.
Suspend the crane scales on the lower hook of a crane and close the safety bracket.
The crane scale’s upper eyelet should rest in the saddle (2).

15 HFD-SH-e-1810
7 Operation
7.1 Safety instructions
Danger
Risk of injury due to falling loads!
Takegreat carewhenoperatingthe craneandfollowthegeneral
rules for crane operation.
Check all parts (hook, eyelet, rings, rope slings, cables, chains
etc.) for excessive wear or damage
If faults can be seen on the safety bracket of the hook or if it
is missing completely, the balance must not be used
Work only with appropriate speed
Always avoid vibrations and horizontal forces. Avoid any kind
of shock, torsion and oscillating (e.g. caused by inclined
suspending)
Do not use the crane scales for transporting loads.
Do not stand or go under suspended loads.
Do not use on building site.
Keep always an eye on suspended loads.
(example)
Do not exceed the nominal load of crane, crane scales or any
kind of load attachment devices at the crane scales.
When weighing dangerous goods such as melted mass,
radioactive material), observe the prescriptions for handling
dangerous goods!

HFD-SH-e-1810 16
7.2 Loading the crane scales
For good weighing results observe the following, illustrations see next page:
Only use load attachment devices which guarantee a one-spot suspension and where the
scales can be suspended freely.
Do not use too large load attachment devices which do not guarantee any one-spot
suspension.
Do not use multiple suspensions.
Do not pull or push the load or the loaded balance.
Do not pull the hook horizontally.
7.3 Loading the balance
1. Position the crane scales over the load.
2. Move downwards the crane scales until the load can be suspended on the balance. Reduce
the speed when the respective height is going to be reached.
3. Suspend a load. If necessary, ensure that the safety bracket is closed. If the load is fixed by
slings, ensure that the slings rest completely on the saddle of the load attachment device.
4. Lift-off the load slowly.
When the load is fixed by slings, ensure that the load is well balanced on both sides and that
the slings are correctly positioned

17 HFD-SH-e-1810
Only use load attachment devices
which guarantee a one-point
suspension and where the scales
can be suspended freely.
Do not use too large load attachment
devices which cannot guarantee a
one-point suspension.

HFD-SH-e-1810 18
Do not push or pull
Do not pull the hook horizontally
Do not use multiple suspensions

19 HFD-SH-e-1810
8 Menu
8.1 Navigation in the menu:
Call function
Switch-on balance and during the selftest
press the TARE button.
"P1 - - -" will be displayed.
Enter password "000" :
Select a number by the M+ key
Increase the numeric value using the TARE key
Confirm by the ZERO key. The first function „F0 cal“ is
displayed.
Select function
The TARE button allows to select the individual functions one
after the other.
Select setting
Confirm the selected function by the ZERO button. The
current setting will be displayed.
Change settings
Use the TARE button to switch over into the available
settings.
Confirm setting
Press the ZERO button, the balance returns into the menu.
Exit menu / Return to
weighing mode
Press the M+ key.

HFD-SH-e-1810 20
8.2 Overview:
Function
Description
F0 cal
Adjustment, see chap. 9 in the HFD user manual
F1 cap
Set weighing balance
capacity (max) /
balance type
threer
600
Three-range balance
Modifications may only be carried out by a specialist with competent knowledge.
1500
3000
6000
12000
single
600
Single-range balance
1500
3000
6000
12000
Dual r
600
Multi-range balance
1500
3000
6000
12000
Dual i
600
Multi-interval balance
1500
3000
6000
12000
F2 sp
Slow
Reaction speed
selectable slow, medium, fast
mid
fas
F3 inp
Display internal resolution
F4 GRA
Gravitation constant at place of installation
F5 com
mode
wifi
Not documented