2. Service
Assembly/Module Diagnostic Trees (Diagnostic Section 3)
84
A2 Hot-Wire Ionizer Diagnostic Tree
This functional subsection describes the A2 hot-wire ionizer diagnostic tree
for the 5071A Primary Frequency Standard. Performance of these tests is
indicated by the presence of either a self-test or fatal error that reports a hot-
wire ionizer fault.
3.1.1.1.0 CBT Hot-Wire Resistance Test
1
Power off the 5071A.
2
Unplug cable from A2J1 and A2J2.
3
Using a 4-wire Ohm Meter, measure the resistance across pins
1 and 6 on the CBT cable.
QUESTION:
Is the resistance between 0.1 and 0.25
Ω
?
If Yes:
Go to, 3.1.1.1.1.
If No:
Recheck results and Ohmmeter, then replace CBT.
3.1.1.1.1 CBT Hot-wire Resistance-to-Ground Test
1
Measure the resistance across pins 1 and 4 on the CBT cable.
QUESTION:
Is the resistance greater than 200 k
Ω
?
If Yes:
Go to, 3.1.1.1.2.
If No:
Recheck results and DMM, then replace CBT.
3.1.1.1.2 Hot-Wire Monitor Test (No Current)
1
Remove instrument power.
2
Remove A2 CBT Controller.
3
Install the long extender board (05071-60052) into A2 slot.
4
Turn on the 5071A.
5
Use SCPI command
syst:print?
.
(Terminal-to-instrument via RS-232C data communication required.)
QUESTION: Is
HW Ionizer:
between -0.5 and +0.5 V?
If Yes:
Go to, 3.1.1.1.3.
If No:
Remove power, replace A7, and retest.
Содержание 5071A
Страница 2: ......
Страница 40: ...1 Performance Tests Verifying Specifications 5071A Complete Performance Tests 24 ...
Страница 48: ...2 Service Pre Troubleshooting Information 32 Figure 2 1 Instrument Top View ...
Страница 147: ...3 Theory of Operation Functional Block Descriptions 131 Figure 3 2 5071A Overall Block Diagram ...
Страница 148: ...3 Theory of Operation Functional Block Descriptions 132 Figure 3 2 5071A Overall Block Diagram Continued ...
Страница 164: ...3 Theory of Operation Functional Block Descriptions 148 Figure 3 3 A1 Power Supply Distribution Schematic Diagram ...
Страница 166: ...3 Theory of Operation Functional Block Descriptions 150 Figure 3 4 A1 Slot Module Interconnect Diagram ...
Страница 168: ...3 Theory of Operation Functional Block Descriptions 152 Figure 3 5 Power Supply Block Diagram ...
Страница 171: ...3 Theory of Operation Functional Block Descriptions 155 Figure 3 7 Opt 048 A1 Slot Module Interconnect Diagram ...
Страница 172: ...3 Theory of Operation Functional Block Descriptions 156 Figure 3 8 Opt 048 Power Supply Block Diagram ...
Страница 173: ......
Страница 175: ...3 Theory of Operation Functional Block Descriptions 159 Figure 3 9 A1 Component Locator Diagram ...
Страница 194: ...5 Replaceable Parts How To Order A Part 178 ...
Страница 197: ......