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This manual and Marks All safety messages are identified by the following, “WARNING” or “CAUTION”, of ANSI Z535.4 (American National Standard Institute: Product Safety Signs and Labels). The meanings are as follows: A potentially hazardous situation which, if not avoided, could WARNING result in death or serious injury.
GX-A/GF-A Maintenance manual 1. Introduction For smooth maintenance, the products must be technically understood, and the required equipment and tools must be prepared. Since the GX-A/GF-A series electronic balance is a precision instrument, proper operation cannot be guaranteed if the maintenance is performed under unsatisfactory conditions.
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GX-A/GF-A Maintenance manual One set of jig for disassembling or reassembling the Mechanical unit (7PA:GXA-JIG) (1) A base jig (GXA-1/8) (2) A spacer for positioning the beam (1) (GXA-2/8) (3) A bolt for holding the beam (1) (GXA-3/8) (4) A bord for positioning the beam (1)(GXA-4/8) (5) A plate for positioning the beam (1)(GXA-5/8) (6) A jig for positioning the fulcrum flexure (GXA-6/8) (7) A jig for positioning the force coil bobbin GXA-7/8)
GX-A/GF-A Maintenance manual 2. Principles of operation The GX-A/GF-A balances work on the principle of "Force Restoration". Any change in the load on the weighing pan causes a Position Beam Lever to pivot on two Fulcrum Flexures (refer to diagram below). Attached to this beam is a bobbin (wound with fine wire), called the "Force Coil", which floats in a permanent magnet, called the "Force Motor".
GX-A/GF-A Maintenance manual 2.1 Corrective Maintenance Outline Performance test To perform the corrective maintenance, defects must be located and their cause determined. The easiest way to locate a defect is to perform an operation check. Corrective maintenance procedure Corrective maintenance is described by using a flowchart and a troubleshooting table.
GX-A/GF-A Maintenance manual 3. Performance Test The following test procedures determine whether the balance (GX-A/GF-A series) works properly. The internal temperature of the balance must be approached to the room (the air) temperature enough, allow half an hour warm-up prior to conducting the performance test. 3.1 Performance Test Procedure Verify the following points: External view...
4002 6002 10002 10kg ±0.02g 6001 ±0.1 g 10001 10kg Internal mass repeatability (GX-A series) Calibrate using the internal mass. Perform this three times, verify that the all data be within the specifications. GX-A series Model Masses Specifications 200g 300g ±0.010 g...
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GX-A/GF-A Maintenance manual Corner load error Place the specified mass at the center of the pan (1) and record the displayed value. Then place the mass, at positions 2, 3, 4, 5 then 6. Verify that the difference between the values at the center and at each position (the cross marks 2, 3, 4, and 5 are half the distance from the center of the pan to the corner edge) is within the specifications.
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GX-A/GF-A Maintenance manual Repeatability Place the specified mass at the center of the pan and remove. Record the displayed values with and without load. Repeat the test ten times (one set). Get 10 span data by subtracting the displayed value when no load is applied from the displayed value when load is applied. Obtain the standard deviation from the 10 data and verify that it is within the specifications.
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GX-A/GF-A Maintenance manual Linearity / Hysteresis (1)GX-A/GF-A series Linearity/ Hysteresis After calibration by using an external weight close to the weighing capacity, place the specified mass one by one on the pan, and check the difference between true value and display value (linearity).
GX-A/GF-A Maintenance manual 4. Corrective Maintenance Perform corrective maintenance for the GX-A/GF-A series by referring to the maintenance flowchart and the troubleshooting table. The troubleshooting table describes the possible cause and solution to facilitate corrective maintenance. Perform corrective maintenance according to the error (the letters refer to nodes on the maintenance flow chart): Type A: Replacing, disassembling, or assembling the force motor unit Type B: Replacing or adjusting electrical parts...
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GX-A/GF-A Maintenance manual Problem Cause Check Solution Type Unstable Force motor, Check the operation of weight / Replace analog board weighing Analog board temperature offset A/D. assembly “6-13 data, assembly (Refer Method repeatability identifying defect location”) error Then if it is OK, the cause will be Check the force motor the force motor.
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GX-A/GF-A Maintenance manual Problem Cause Check Solution Type Temperature Check the operation of weight / In the T1 display of check mode rror 0 sensor, temperature offset A/D. menu, check the absolute value (Refer to “6-13, 1 Method of Analog and dispersion (Refer to 6-7).
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GX-A/GF-A Maintenance manual Problem Cause Check Solution Type Press the PRINT key to change (U1) The EEPROM version is not rror 8 correct newer the EEPROM version. EEPROM version. EEPROM (U9) on the error main board (U1) EEPROM has not been initialized. While holding down...
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GX-A/GF-A Maintenance manual Table-1 Specifications of each power-supply voltage on the main board and display board Circuit symbol Specifications Check point (Check pad) Voltage generation element 3.1V – 3.5V - LG 4.7V – 5.3V - LG U7, U8 9.5V – 10.5V - LG 3.0V –...
GX-A/GF-A Maintenance manual 4.2 Maintenance Flowchart Replace Disassemble the (7PZ6594) Main board force motor or EEPROM ? Clean the force motor Reassemble the force motor Coarse adjustment of the force motor Analog board ? (7PZ46595) Confirming the operation of internal mass(GX-A) Page 16...
GX-A/GF-A Maintenance manual 5. Force Motor Disassembly and Reassembly This chapter describes the procedures and notes for the flexure assembly replacement, bobbin cleaning, and adjustment after reassembling the force motor. Notes: The disassembly and reassembly should take place in a dust free environment. Adjustments and confirmations are needed after reassembly for linearity, repeatability, creep, hysteresis and corner load error.
② Disconnect the cable from the A/D board. ③ Remove the mass receiver. (Pan head screw M4x6 with coned disk spring mass receiver , 2pcs) GX-A series only. mechanical unit ④ Remove the mechanical unit. (Allen head screw M5x10 with coned disk spring , 2pcs) 3.
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GX-A/GF-A Maintenance manual Pan support arm ⑦ Secure the roberval on the base jig using the allen head screw M5 x10( 3pcs ) and the allen head screw M4x15( 1pc) ⑧ Remove the Pan support arm. ( Short head wires torx screw M4x10, 3pcs) ⑨...
GX-A/GF-A Maintenance manual 5.2 Assembly 1. Assembling the 2nd Beam unit ① Secure the 2nd Beam to the jig for assemble the beam(2). ② Secure the 2nd Lever to the 2nd Beam A jig for assembling (Allen head screw M4x8 WS,15kgf・cm, the Beam(2) 2pcs) ③...
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GX-A/GF-A Maintenance manual ⑤ Remove the bord for positioning the beam (1). ⑥ Install the fulcrum flexures perpendicularlye, using the jig for positioning the fulcrum flexure(1) (Pan head screw with washer M4 x6 , A jig for positioning the fulcrum flexure(1) 15kgf・cm, 4pcs) ※In case of 10mg type, Roberval side: Pan head screw with...
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GX-A/GF-A Maintenance manual ⑩ Secure the Counter weight.(Pan head Counter weight screw M3x40,1pc and Nut with spring washer M3,1pc) A bolt for holding ⑪ Remove the bolt for holding the beam the beam(1) (1) and the spacer for positioning the beam (1).
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GX-A/GF-A Maintenance manual ⑮ Secure the Magnet unit2(yoke) (Pan head screw M4x8 WS, 12kgf・cm, 2pcs) Magnet unit2(Yoke) ⑯ Secure Magnet unit1(Shield plate) (Shield plate mounting screw , 2pcs). Use the pan head screw M3x80 as jig. Magnet unit1(Shield plate) ⑰ Secure the position sensor (Pan head screw M3x6 WS, 2 pcs) ⑱...
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GX-A/GF-A Maintenance manual 5. Installing the mechanical unit to the upper case ① Check the insulation of the 2nd beam unit (the mechanical unit alone). Measure with multimeter resistance between one end of the force coil and the frame. Confirm that the measured value is the same as that of when the electrodes of the multimeter are open.
GX-A/GF-A Maintenance manual 5.3 Cleaning the Magnet Assembly and Bobbin The magnet assembly and the bobbin will require cleaning if the balance has a repeatability problem. Particles of metal, dust or other foreign material can collect around the bobbin. If such material touches the bobbin, the bobbin will not move correctly.
GX-A/GF-A Maintenance manual 6. Adjustments 6.1 Adjustment Flow Chart Force motor assembly Check the maintenance main board Initial setting (initialization, model type selection...if necessary) Coarse operation check (A/D operation) Coarse adjustment (calibration and corner load adjustment) Temperature adjustment (enter high and low temperature data) Fine adjustment (corner load adjustment, linearity, hysteresis) Internal parameter setting (selection of weighing units and serial number setting) Performance test (corner load adjustment, repeatability, linearity)
GX-A/GF-A Maintenance manual 6.2 General Precautions The data structure is shown below. Functions listed nearer to the bottom are more basic. If the specific data is adjusted, all data listed above the adjusted data must also be adjusted. Calibration Linearity Temperature adjustment Corner load adjustment Repeatability...
GX-A/GF-A Maintenance manual 6.3 Check Mode Check mode consists of three modes: Data adjustment mode, function setting mode and basic setting mode. 1. Entering the check mode GX- 203A/303A/403A/603A/1003A/1603A 2002A/3002A/4002A/6002A/10002A 6001A/10001A GF- 123A/203A/303A/403A/603A/1003A/1603A 1202A/2002A/3002A/4002A/6002A/10002A 6001A/10001A Step 1. Verify that the display is OFF. Step 2.
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GX-A/GF-A Maintenance manual 2. Check mode menu Start from step 5. Only the maintenance main board display this Item.(The usual product do not display) Press While holding down While holding down PRINT RE-ZERO SAMPLE Press press twice. PRINT PRINT Basic setting mode Data adjustment mode Function setting mode PRINT...
GX-A/GF-A Maintenance manual 6.4 Check Mode Menus 1. Internal count display GX- 203A/303A/403A/603A/1003A/1603A 2002A/3002A/4002A/6002A/10002A 6001A/10001A GF- 123A/203A/303A/403A/603A/1003A/1603A 1202A/2002A/3002A/4002A/6002A/10002A 6001A/10001A d-d5p While in the display, press the PRINT key to display the internal count. Use the SAMPLE key to go to the next data. 1.23 1.234 100)
GX-A/GF-A Maintenance manual 6.5 Initialization <CAUTION> · Do not proceed with this initialization if you cannot prepare a temperature-controlled room. (It is necessary to adjust temperature data after this initialization) Note that the following data is initialized by this operation. •...
GX-A/GF-A Maintenance manual 6.6 Model type Selection (Only for maintenance electric board) Model type selection is available for the maintenance board only. Model selection procedure Follow the procedure below to select the balance model type. Step 1. Verify the following item of the 7PZ-6594B/C (Main board for the maintenance). □...
GX-A/GF-A Maintenance manual 6.7 Coarse Operation Check & Adjustment 1. A/D count check The A/D count can be checked in the check mode. Follow the procedure below to verify the A/D values for weight data (D0) and temperature data (T1). d-d5p Step 1.
GX-A/GF-A Maintenance manual 6.8 Coarse Adjustment 1. Calibration With nothing placed on the pan, warm up the balance for at least half an hour. Calout Calibration is performed in the check mode display. Follow the procedure below to calibrate. d-d5p Step 1.
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GX-A/GF-A Maintenance manual Step 4. In the D2 display, place an external mass on the center of the pan and at four positions half the distance from the center of the pan to the edge. Adjust the corner load adjusting screws so that the difference between the values in the center and each position will be within the specification.
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GX-A/GF-A Maintenance manual 3. Hysteresis check Apply a preliminary load by placing and removing a load with the same weight value as the full scale value. Perform this pre-load three times. Note: The corner load error has a bad effect on the linearity adjustment or linearity and hysteresis check.
GX-A/GF-A Maintenance manual 6.9 Temperature Adjustment A room or chamber that can be set at 10°C and 30°C is required for this adjustment. The balance must stabilize at each temperature for more than 4 hours before the data is taken. Input high temperature data initially, then input low temperature data.
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GX-A/GF-A Maintenance manual 2. Temperature adjustment check Step 1. After inputting the low temperature data, keep the temperature. Step 2. Press the RE-ZERO key to show zero. Note the zero point reading. Place a mass in table below on the pan and note the span reading. The span data is calculated after subtracting the zero point reading from the full point reading.
GX-A/GF-A Maintenance manual 6.10 Fine Adjustment 1. Corner load adjustment In the D2 data mode, place an external mass on the center of the pan and at four positions half the distance from the center of the pan to the corner edge shown in a figure below. Verify that the difference between the values at the center and at each position is within the specifications.
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GX-A/GF-A Maintenance manual 2. Linearity adjustment (lnr-2 , 3) / Linearity and Hysteresis check First, warm up the balance at room temperature for at least 1 hour before carrying out the adjustment. Apply a preliminary load by placing and removing a load with the same weight value as the full scale value.
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GX-A/GF-A Maintenance manual Step12. Remove all the mass on the weighing pan, place mass C and press the PRINT key. lnr-5 After it stabilized, is displayed. (Press the CAL key to cancel the Step13. operation.) Add mass A (confirm to place mass C and mass A on the weighing pan) and press Step14.
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GX-A/GF-A Maintenance manual Linearity and Hysteresis check Calibrate by using the calibration mass in table below. After calibration, in the D2 data mode, place the specified check mass in the table below one by one on the pan, and check that the difference between the true value and the displayed value is within the specifications (linearity).
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Step 3. Press the PRINT key. The motor starts and adjusts the internal mass position correctly. Cal 0 Step 4. is displayed. Check the standard mass for calibration in table below. Model (GX-A series) Standard masses 200g 300g 400g 600g...
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GX-A/GF-A Maintenance manual Step 7. Place the calibration mass specified in step 4 on the pan. Press the PRINT key. < is displayed. (Example of the GX-203A) Step 8. After it stabilized, is displayed. Step 9. Remove the mass. (3) Fine adjustment of internal mass value d-d5p Step 1.
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GX-A/GF-A Maintenance manual Model (GX-A series) Standard masses Specifications 200g 300g 400g ±0.010g 600g 1003 1000g 1603 ±0.10g 2002 3002 4002 ±0.15g 6002 10002 6001 ±0.5g 10001 (6) Calibrate using the internal mass and verify the fine adjustment error (operation (4)-(5)).
GX-A/GF-A Maintenance manual 6.11 Parameter Settings 1. Serial number setting Follow the procedure below to set the serial number. Unit , Step 1. Display the function setting mode after getting into check mode shown on page 28,29. Step 2. Press the SAMPLE key twice. is displayed.
GX-A/GF-A Maintenance manual 6.12 Half-initialization Half-initialization changes all the user settings(*1) to the default values. Follow the procedure below. Unit Step 1. Display the function setting mode after getting into check mode shown on page 29. initHf Step 2. Press the SAMPLE key several times. is displayed.
GX-A/GF-A Maintenance manual 6.13 Method of identifying defect location (Electrical part or Mechanical part) In this chapter it explains about how easily you can check the cause of malfunction in the mechanical parts or in the electrical part, without disassembling the balance. It is advantageous if the defect is “unstable data”...
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3-23-14 Higashi-Ikebukuro, Toshima-ku, Tokyo 170-0013, JAPAN Telephone: [81] (3) 5391-6132 Fax: [81] (3) 5391-6148...
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