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Service Manual Variants: for seca 634 / 635 6341321004 6341321009 6357021009 6357021099 Service Manual Number 6357021229 6357021289 17-05-01-321-d 6357021249 Valid as of: 06.07.2011 Description: Large platform Electronic scale with a wide measurement range specially for adipose patients. Content: Short description display module...
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Brief description of the display module Introduction The display modules belong to the family of seca electronic modules and are used to display a weight measured with a suitable module and transferred via the SeSAM bus (Seca’s Serial Autoconfiguring Multicontroller bus). Furthermore, the display modules accommodate the operating elements and can process the weight (hold, tare, etc.).
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Power supply Power supply is provided via the SeSAM bus. Operation With the exception of a start button that might be available, the connected buttons can be configured as required for the particular model. These buttons can be pressed just lightly or longer (longer than 1.5s).
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Recalibration In order to compensate for linear measuring errors of the scale, which can, for instance, occur as a result of the different forces of gravity at different geographical points, the module has a recalibration function. To initiate the function, another button must be pressed when the scale is started. The verification counter is then displayed which is incremented whenever the scale is recalibrated.
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Technical data Supply voltage: 2.7V - 3V and 2.7V - 15V (via SeSAM bus) Supply current: typ. 0.5mA + power supply for backlighting (typ. 100mA) Quiescent current: typ. 2µA Operating temperature: approx. 0°C to 50°C Storage temperature: -10°C to 60°C Dimensions: 74mm x 50mm x 23mm small display...
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EEPROM is integrated which is used to configure the module. A connection to the SeSAM bus (Seca’s Serial Autoconfiguring Multicontroller bus) is provided via which the scale can be calibrated and additional modules can be connected.
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Service manual Description of the electronics Display (only DMS low-end module and SLC highend) Whenever eight new measured values are available, i.e. approx. every 0.8 s, the weight is displayed. The display is an LCD which is controlled by duplex operation. A maximum of five digits as well as a few special characters can be displayed.
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Service manual Description of the electronics If the start button is directly connected to this interrupt input, a button is obtained which is only active when the scale is switched off. It can be fitted under the platform, for instance, so that the scale is started by briefly stepping on it.
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Service manual Description of the electronics Time base From the quartz’s 4.19MHz a time base is derived which controls all timed processes in the scale. These are, for instance, various timeouts and the on-time. After expiry of the on-time, the supply voltage for the analog part, for voltage measurement and for the EEPROM is switched off.
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Service manual Description of the electronics Technical data Supply voltage: Load cell voltage + 0.5 V to 15 V Supply current: approximate load cell current Zero-signal current: typ. 2µA Operating temperature: approx. 0°C to 50°C Storage temperature: -10°C to 60°C 05.08.03 /Jensen / Rei 34-34-00-645 b...
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Service manual Description of faults Please refer to the operating instructions to make sure that scale malfunctions are not caused by operation faults. Should any faults occur, the following table will help you to identify the cause of the fault. Fault description Possible cause Remedy...
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Service manual Description of faults Fault description Possible cause Remedy Er:X:14 Fault in the kg value Wrong coefficients in the module’s ROM, reprogram and readjust the calculation scale Er:X:15 Recalibration fault Reference weight outside the permitted range or operating fault ...
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General: General: Seca scales with modular electronics are fitted with a software-controlled calibration device that is operated using the existing controls. This device can be used to recalibrate the scales or to set the scales to different GAL values. During development of the calibration device, special attention was paid to the following requirements: •...
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Vogel & Halke File: 00603_e1.doc seca Created on: 30.06.1998 Printed on: 07.07.1999 Holger Panier / SE Pressing the kg/lbs key for less than 1.5 seconds causes the weight shown on the display to be increased or decreased by 10 g (depending on the mode currently selected). As the resolution of the display is lower, the displayed value will not necessarily be increased or decreased each time the kg/lbs key is pressed.
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Vogel & Halke File: 00603_e1.doc seca Created on: 30.06.1998 Printed on: 07.07.1999 Holger Panier / SE Summary of a typical recalibration sequence: Summary of a typical recalibration sequence: Action carried out by the user Result The scales are switched off.
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1 (2) PC configuration program page Instructions for PC-based configuration PC-based configuration is used for diagnosis or recalibration of all seca scales with modular electronics. The following equipment is required: • PC with serial interface (RS -232) • seca software 'SERVA”...
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2 (2) PC configuration program page Standard case Connection to the existing display unit port. The display can instead be connected to the second modular socket of the service module. DMS module with integrated display 08-06-18-082 If there is no modular socket on the back of the PCB, retrofit one.
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Service Manual Replacement instructions seca 634, 635 The references to pages and items relate to the replacement instructions drawing, Pages 4 – 8. The power supply unit must not be connected. We urgently recommend that you remove the battery pack before starting any work on the unit (see operating instructions).
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Service Manual Replacement instructions Dismantling the holder for mains socket and bubble level (page 7) Pull off the modular cable (item 7.1). Remove the screw (item 7.2) and lift off the socket housing (item 7.3) and the cover (item 7.4). Remove the 2 screws (item 7.5) and take out the mains connection (item 7.6).
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Service Manual Replacement instructions Assembly (the references to pages and items relate to the replacement instructions drawing, pages 4-8) Assemble in the reverse order of disassembly. Please note the following points: Fitting a new load cell (page 5): After replacing load cells, the scale must be readjusted and calibrated if required. For adjustment, please follow our calibration instructions, document no.
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Bubble level holder, rear mounting for Mod. 634 to ser.no.163404408xxxx, for Mod. 635 to ser.no.163504408xxxx 01-17-02-215-009 Bubble level holder new, down mounting for mod. 634 from ser.no. 163404508xxxx, for mod. 635 from ser.no. 163504508xxxx 01-17-01-203-009 Bubble level 08-04-05-360-009 Cover mains socket...
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Service manual Spare parts list 03.02.2011/ Rei 30-34-00-056c...
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34-02-04-340-009 Wall mounting bracket (38) 68-32-10-252-009 Plug in power supply unit seca 447 68-32-10-263-009 Plug in power supply unit Switch mode seca 440 for Mod 634 to ser. no. 163403609xxxx for Mod 635 to ser. no. 163503609xxxx 68-32-10-265-009 Plug in power supply unit Switch mode seca 400 for Mod 634 from ser.
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Service manual Spare parts list 03.02.2011/ Rei 30-34-00-056c...
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