KERN ECB, KERN ECE, ECB 10K10, ECB 20K20, ECB 50K50 Service Manual

KERN & Sohn GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]

Tel: +49-[0]7433-9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com

GB

Service Manual

Electronic Platform Scales

Page 2

KERN ECB / ECE

Version 2.0 4/2008

ECB/ECE-SH-e-0820

GB

KERN ECB / ECE

Version 2.0 4/2008

Service Manual
Electronic Platform Scales

Table of Contents

1 Features.......................................................................................................................3

2 Calibration Procedure (CAL) .....................................................................................3

3 Internal Calibration Procedure (Linearity Adjustment) ...........................................4

4 Display Segment Test .............................................................................................. 5

5 Functional Block Diagram / Description...................................................................6

5.1 Functional Block Diagram.....................................................................................................6

5.2 Function Description.............................................................................................................7

6 Trouble Shooting........................................................................................................ 8

7 To Replace PCB.......................................................................................................... 9

8 Schematics................................................................................................................ 10

9 Components Layout................................................................................................. 12

2 ECB/ECE-SH-e-0820

ECB/ECE-SH-e-0820 3

1 Features

• Zero weight function

• Negative value indication

• Low battery indicator

• Auto zero

• Display segments test function

• Auto off function in battery mode - enable/disable (only ECB)

• Overload protection

• Overload indication

• Digital span calibration

• Digital internal calibration

• Operated by 6 x AA size alkaline batteries

• Rechargeable battery as option

• Zero tracking - enable/disable (only ECB)

• Backlight - 3 modes (only ECB)

2 Calibration Procedure (CAL)

1. Turn scale on and allow the unit to acclimatize and stabilize for 10 minutes.

2. Press and hold the [Tare] key for approx. 3 seconds. Display will show [CAL] and then
the required calibration weight.

3. Gently place the correct calibration weight on the center on the weighing pan.

4. Wait until the display shows [ F] and then return to normal weighing mode
automatically.

5. Remove the calibration weight and press the [TARE] key to reset the zero point.

In case [ E] is displayed instead of [ F], this indicates a calibration
procedure error. Turn the scale off and then on and repeat the procedure.

3 Internal Calibration Procedure (Linearity Adjustment)

1. Remove the bottom cover under the PCB of the scale.

2. Connect J1 on the main board by soldering the pads together.

4 ECB/ECE-SH-e-0820

3. Place scale on a hard level surface. Turn scale on. Display shall show the internal
counts.

4. The internal counts shall fall in the range from 3 000 to 6 000. In case out of this
range, remove the four screws from the main board and lift it to see the rear side
of the main board.

5. Connect J9 left side or right side to increase or reduce the reading.
Connecting or disconnecting pads on J5, J6 or J7 can fine tune the reading.