GRAPHTEC GL820 User manual

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SERVICE MANUAL
820
GL820-UM-251
GL820-UM-251-02-9370

GL820-UM-251-9370 i
HISTORY OF REVISIONS
No. Date issued Description of revision Page Edition
1 10.02.18 First Printing All 01
2 10.04.06 The size of screws were corrected. 3-5, 3-8 02
3
4
5

GL820-UM-251-9370 ii
TO ENSURE SAFETY
This Service Manual has been compiled for the purpose of facilitating repair and maintenance of the GL820
midi LOGGER by Graphtec service personnel and other persons who have undergone equivalent technical
training.
Maintenance or repair by unauthorized service personnel is to be strictly avoided. Because the GL820
contains numerous internal components with a high electric potential, such work by unauthorized service
personnel could cause human injury or serious damage to the GL820 midi LOGGER.

GL820-UM-251-9370 iii
CONTENTS
1. CONFIGURATION ................................................................................. 1-1
1.1 Model Conguration .....................................................................................................1-1
1.2 Accessories and Options .............................................................................................1-1
2. UPGRADING THE FIRMWARE ............................................................ 2-1
2.1 Note for the rmware upgrading ..................................................................................2-1
2.2 How to Upgrade the GL820 Flash ROM from the USB memory device ...................2-1
3. DISASSEMBLY AND REASSEMBLY ................................................... 3-1
3.1 Notes on Disassembly and Reassembly ....................................................................3-1
3.2 Removing the Input Terminal Unit ...............................................................................3-2
3.3 Removing the Side Pads ...............................................................................................3-3
3.4 Disassembling the Top Cover and the Bottom Case Assembly .............................. 3-4
3.5 Replacing the Main Control Board ..............................................................................3-5
3.6 Replacing the Control Panel Board ............................................................................ 3-6
3.7 Replacing the LCD and the Top cover .........................................................................3-7
3.8 Replacing the AMP Board ........................................................................................... 3-8
4. SETUP PROCEDURES ......................................................................... 4-1
4.1 Entering the System Setup Menu ................................................................................4-1
4.2 AC Line cycle Setting ................................................................................................... 4-3
4.3 Performing Setup1 (Voltage Input) ............................................................................. 4-4
4.4 Performing Setup2 (Room Temperature Compensation) ......................................... 4-8
4.5 Performing Setup3 (RTD)............................................................................................4-12
5. INSPECTION AND CHECK PROCEDURES ........................................ 5-1
5.1 Preparations for inspections .......................................................................................5-1
5.1.1 AC Line Setting .....................................................................................................................5-1
5.1.2 Sampling setting ....................................................................................................................5-1
5.1.3 Copy the condition settings le .............................................................................................5-1
5.1.4 How to load the condition settings le to the GL820 from a USB memory device ...............5-2
5.2 Voltage Measurement Accuracy ................................................................................. 5-6
5.3 Temperature Accuracy ................................................................................................. 5-9
5.4 RTD Accuracy ..............................................................................................................5-11
6. PARTS LISTS ........................................................................................ 6-1
6.1 Recommended Parts List .............................................................................................6-1
6.2 Parts Lists ......................................................................................................................6-2
6.2.1 Outer Casing .........................................................................................................................6-2
6.2.2 Bottom Parts .........................................................................................................................6-3
6.2.3 Top Parts .............................................................................................................................. 6-4
6.2.4 Bottom Case ........................................................................................................................ 6-6
6.2.5 Terminal Unit ........................................................................................................................ 6-6
6.2.6 Standard Accessories ...........................................................................................................6-7

7. Block Diagram ...................................................................................... 7-1
7.1 Main Unit Power Block & Main Control ....................................................................... 7-1
7.2 Main Control Block ........................................................................................................7-2
7.3 AMP Block ......................................................................................................................7-3
7.3 Details of the AMP .........................................................................................................7-4

GL820-UM-251-9370 1-1
1. CONFIGURATION
1. CONFIGURATION
1.1 Model Configuration
GL820 : 20-channel model with color monitor and internal memory
1.2 Accessories and Options
Unit name Model
name Description
Logic / Alarm cable B-513
DC Drive Cable B-514 Same as GL200/450/500
Battery Pack B-517 Same as GL200/450/500
Humidity Sensor B-530 Same as GL200/450/500
Extended Terminal Base Unit B-537 Option
20 Ch Extended Terminal Unit B-538 Option
Rod-shaped K-type thermocouple RIC-410
K-type thermocouple for static surfaces RIC-420
L-shaped K-type thermocouple for static surfaces RIC-430

GL820-UM-251-9370 1-2
1. CONFIGURATION

GL820-UM-251-9370 2-1
2. UPGRADING THE FIRMWARE
The version of your GL820’s rmware can be upgraded by rewriting the ash ROM on the pertinent circuit
boards. You can upgrade the rmware by loading the update program to a USB memory device.
2.1 Note for the firmware upgrading
• Save the measuring condition to the internal memory or the USB memory before the rmware upgrade.
• Don't turn off the power during upgrading the rmware.
2.2 How to Upgrade the GL820 Flash ROM from the USB memory device
Preparations for the upgrade
Firmware :MainVerxxxRevxxxxAxx.GL820 ← Main Program le for GL820
:PatternVerxxxRevxxxxAxx.GL820← Font le for GL820
(1) Connect the AC adapter for the GL820.
(2) Turn on the GL820.
(3) Copy the two les to a USB memory device from the computer.
(Copy the two main program les to root directory of a USB memory. Do not copy them to any folder.)
How to upgrade
(1) Insert the USB memory device containing the main upgrade program into the GL800's USB port.

GL820-UM-251-9370 2-2
2. UPGRADING THE FIRMWARE
(2) Turn on the GL820 to display the menu below.
And then select the upgrade program le by using the [UP Arrow] direction key or the [Down Arrow]
direction key.
(3) Press [ENTER] key to execute the upgrade.
(4) Wait until the display shown below appears or until the beeper sound stops.
Note:
Don't turn off the GL820 until this process is nished.
The following message will appear on the GL820 display in yellow characters when the upgrade is
complete. Also the beeper will sound for 5 seconds.
“Please Turn Off the Power. I have locked up.”

GL820-UM-251-9370 2-3
(5) Turn off the power to the GL820 when the above message is displayed or when the beeper sound
stops.
(6) Delete the two program les from a USB memory device.
This is to avoid upgrading the rmware by mistake.

GL820-UM-251-9370 3-1
3. DISASSEMBLY AND REASSEMBLY
3. DISASSEMBLY AND REASSEMBLY
3.1 Notes on Disassembly and Reassembly
• During disassembly, disconnect the cables from the specied connectors as necessary.
• During reassembly, double-check to ensure that the proper cables have been correctly re-connected to
the pertinent connectors.
• Some areas of the control panel unit possess a high electrical potential, so exercise caution to avoid an
electrical shock.

GL820-UM-251-9370 3-2
3. DISASSEMBLY AND REASSEMBLY
3.2 Removing the Input Terminal Unit
Disassembly
(1) Remove the input terminal unit as shown in the picture below.
Pull the terminal unit out towards the direction indicated by the arrow while pressing the two locks at the
bottom of the unit.
(1) Press the two locks in the direction indicated by arrows.
(2) Pull the unit out towards the direction indicated by the arrow.

GL820-UM-251-9370 3-3
3. DISASSEMBLY AND REASSEMBLY
3.3 Removing the Side Pads
Disassembly
(1) Peel off the left and right side pads from the main unit.
Right side pad
Left side pad
Main unit
Re-assembly
(1) Push the left and right side pads against the main unit and then install them on the main unit.

GL820-UM-251-9370 3-4
3. DISASSEMBLY AND REASSEMBLY
3.4 Disassembling the Top Cover and the Bottom Case Assembly
Disassembly
(1) Remove the input terminal unit from the main unit (See Section 3.3).
(2) Remove the side pads from the main unit (See Section 3.4).
(3) Remove the four M2L8 self-tapping screws from the bottom cover.
(4) Disconnect the connector between the main control board and the AMP board and then remove the top
cover assembly.
M2L8 self-tapping screw
Top cover assembly
Bottom case assembly
Re-assembly
(1) Re-assemble the top cover assembly and the bottom case assembly in the reverse order in which they
were disassembled.

GL820-UM-251-9370 3-5
3. DISASSEMBLY AND REASSEMBLY
3.5 Replacing the Main Control Board
Disassembly
(1) Remove the input terminal unit from the main unit (See Section 3.2).
(2) Remove the side pads from the main unit (See Section 3.3).
(3) Disassemble the top cover assembly and the bottom case assembly (See Section 3.4).
(4) Disconnect the LCD exible cable from the main control board.
(5) Remove the two M2L6 self-tapping screws holding the main control board from the top cover assembly.
(6) Disconnect the connector between the main control board and the control panel board and then remove
the top cover assembly.
M2L6 self-tapping screw
LED exible cable
Main control board
Top cover assembly
Core
Fixing tape
Re-assembly
(1) Re-assemble the main control board in the reverse order in which it was disassembled.

GL820-UM-251-9370 3-6
3. DISASSEMBLY AND REASSEMBLY
3.6 Replacing the Control Panel Board
Disassembly
(1) Remove the input terminal unit from the main unit (See Section 3.2).
(2) Remove the side pads from the main unit (See Section 3.3).
(3) Disassemble the top cover assembly and the bottom case assembly (See Section 3.4).
(3) Remove the main control board (See Section 3.5).
(4) Remove the two M2L6 self-tapping screws holding the LCD bracket, and then detach the LCD bracket.
(5) Remove the four M2L6 self-tapping screws holding the control panel board.
(6) Remove the control panel board from the top cover assembly.
M2L6 self-tapping screw
Top cover assembly
Control panel board
M2L6 self-tapping screw
LCD bracket
Re-assembly
(1) Re-assemble the control panel board in the reverse order in which it was disassembled.

GL820-UM-251-9370 3-7
3. DISASSEMBLY AND REASSEMBLY
3.7 Replacing the LCD and the Top cover
The LCD is supplied together with the top cover assembly.
This is avoiding to get the dust between the LCD and the top cover panel.
Disassembly
(1) Remove the input terminal unit from the main unit (See Section 3.2).
(2) Remove the side pads from the main unit (See Section 3.3).
(3) Disassemble the top cover assembly and the bottom case assembly (See Section 3.4).
(3) Remove the main control board (See Section 3.5).
(4) Remove the key pad from the top cover assembly.
Key pad
LCD bracket
Top cover assembly with LCD
Control panel board
Re-assembly
(1) Re-assemble the LCD and the top cover assembly in the reverse order in which it was disassembled.

GL820-UM-251-9370 3-8
3. DISASSEMBLY AND REASSEMBLY
3.8 Replacing the AMP Board
Disassembly
(1) Remove the input terminal unit from the main unit (See Section 3.2).
(2) Remove the side pads from the main unit (See Section 3.3).
(3) Disassemble the top cover assembly and the bottom case assembly (See Section 3.4).
(4) Remove the four M2L6 self-tapping screws holding the AMP board from the bottom case assembly.
(5) Detach the AMP board from the bottom case assembly.
(6) Remove the two M2.6L6 binding head screws holding the terminal unit connector cover.
(7) Detach the terminal unit connector cover from the AMP board.
M2L6 self-tapping screw
Bottom case assembly
AMP board
Terminal unit connector cover
M2.6L6 binding head screw
Re-assembly
(1) Re-assemble the AMP board in the reverse order in which it was disassembled.
(2) Perform the Setup operations for the GL820 when you replace the AMP board.