ESI 250-DA User manual

mam
JANUARY
T524 S.W. MACADAM AVE. •PORTLAN DO. OREGON
REPLACES OCTOBER 1959

INSTRUCTION MANUAL,
for
MODEL 250-DA IMPEDANCE BRIDGE
CONSISTING OF:
Catalog Sheet C>16 including:
Introduction
Specifications
Model 250-DA Impedance Bridge Instruction Manaual
Lid Instructions From Model 250-DA Bridge
leisin 250 -DA H/59

INSTRUCTION MANUAL
for
MODEL 250-DA UNIVERSAL IMPEDANCE BRIDGE
TABLE OF CONTENTS
I* Controls
1.1 Circuit Selector
1.2 Multiplier Switch
1.3 Main Dial Assembly
1.4 D-Q Dial
1.5 Unknown Terminals
1.6 External Generator Terminals
1.7 External D-Q Terminals
1.8 External Detector Terminals
1.9 Detector Switch
1.10 Generator Switch
1.11 Galvanometer
1.12 Power Switch and AC Amplifier Gain
1.13 AC -DC Switch and AC Generator Gain
1.14 DC Generator Voltage Switch
1.15 AC Generator Tuning Network
1.16 AC Detector Tuning Network
1.17 AC Null Indicator
1.18 AC Amplifier Output Terminals
1.19 Fuse
1.20 Power Indicator Lamp
2. Operating Instructions
2. 1What the Bridge Measures
2. 2Resistors
2.2.1 Measuring Resistors
2.2.2 Things to Watch Out For
2.2.3 Measuring AC Resistance
(Him 250-DA 10/59

TABLE OF CONTENTS (cont. i)
Z,3 Inductors
2.3.1 Measuring Inductors
2.3.2 Series and Parallel Inductance
2.3.3 Things to Watch Out For
2.3.4 Inductance Measurements with DC
2.3.5 AC Voltage Measurement
2.3.6 AC Current Measurement
2.3.7 Sliding Balance
2.3.8 Using an External QRheostat
2.4
Capacitors
2.4.1 Measuring Capacitors
2,4,2. Series and Parallel Capacitance
2.4.3 Things to Watch Out For
2.4.4 Capacitance Measurements with DC
2.4.5 AC Voltage Measurement
2.4.6 Extended Leads
2.4.7 Sliding Balance
2.4.8 Using an External D-Q Rheostat
2. 5Using Bridge Elements
2.5.1 Standard Resistors
2.5.2 DEKASTAT® Variable Resistor
2.5.3 Standard Capacitors
3, Circuit Diagrams
3.1 Series Inductance Bridge
3.2 Parallel Inductance Bridge
3.3 Resistance Bridge
3.4 Series Capacitance Bridge
3, 5Basic Circuits
3.6 Bridge Circuit Diagram
3.7 Generator-Detector Circuit Diagram
3.8 Bridge Wiring Diagram
3.9 Bridge Parts Placement
3.10 Generator-Detector Parts Placement
|e|s| iI250-DA 8/59

TABLE OF CONTENTS (cont. ii)
4. Bridge Element Voltage and Current Limits
5. Convenient Audio Frequency Units
6. Servicing and Repair
6.
1
Preliminary Checking
6o 2Checking Procedure
6. 2.1 Test Equipment and Tools
6,2*2 Trouble Shooting Chart
6.2.3 Checking the DC Generator
6.2.4 Checking the Galvanometer
6.2.5 Checking the AC Generator
6.2.6 Checking the AC Detector
6.2.7 Checking the Range Resistors
6.2.8 Checking the Standard Resistors
6.2.9 Checking the MAIN DIAL DEKASTAT®
6.2.10 Checking the D~Q Rheostats
6.2.11 Checking the Standard Capacitor
6.3 Removing the Chassis from the Case
6.3.1 Removing the Chassis
6.3.2 Replacing the Chassis
6.4 Repairing the Bridge
lelsli I250-DA 8/59