1
SECTION E: THEORY OF OPERATION
E-1
General
E-2
Troubleshooting
E-3
Circuit Descriptions
E-4
Analog-to-Digital Converter
E-5
Ohms-to-DC Converter
E-6
Failsafe Design
E-7
Ultra-Safe Power Supply Scheme
Figure E-1.
Model 630ES Block Diagram
Figure E-1B
Analog-to-Digital Converter Timing Diagram
Figure E-2
Analog Section of IC1 and IC2
Figure E-3.
Constant Diagram (Simplified)
Figure E-4.
LED Display Pin Functions
SECTION F: ROUTINE MAINTENANCE
F-1
General
F-2
Required Test Equipment
F-3
Calibration Procedure
F-4
Battery Replacement Instructions
A
E-7B Failsafe Current Limiting Circuit
