Vishay VT400 - 9 Troubleshooting; 9.1 Errors, Causes and Remedies

Appendix A: Technical Drawings
VT400 Technical Manual, Rev. A5 63 Doc # UM-VT400-EN
Appendix A: Technical Drawings
i. System Block Diagram
24VDC
EXTERNAL
RS232
(ST8) J1
+5V
+5V
+5V
RS232
Driver
Watchdog
MCU
89C51RD
64KB EPROM
1KB RAM
32D I/O Lines
32KB EEPROM
Analog to
Digital
Conversion
&
BAT. TEST
+5V
JP1
Calibration
lock
2 Outputs
1 Input (Tilt)
Isolated
ST3
ST1
ST5
+5V
Power
Supply
Power
Input Filter
Power On-Off
PCB 801
PCB 761
PCB 715
PCB 439
Sel. Current or
Voltage Output
JP1
+5V
ST1
(
ST7
)
J2
(ST9) J4
(ST9) J4
Option
Analog to
Digital
Conv.
0-10VDC or
0-20mADC
Analog
Output
Max 10 X 350Ω
Load Cells
ST1
RS485
Driver
JP1
TER. RES
J3
(
ST2
)
RS-485
ST2
6 Key & PWRNF
Membrane Keyb.
6 Digits LED Display
(LCD Black)
ST1
ST2
+5V
Keyb.
&
LED (LCD)
Driver
ST2
Power Input
9-15VDC