Teledyne T200, Operation Manual, Page: 251 / 425

Teledyne API
– T200 NO/NO
2
/NO
X
Analyzer Operation Manual Troubleshooting & Service
249
WARNING
–
E
LECTRICAL
S
HOCK
H
AZARD
Should the AC power circuit breaker trip, investigate and correct the condition
causing this situation before turning the analyzer back on.
12.7.2. DC POWER SUPPLY
If you have determined that the analyzer‟s AC mains power is working, but the unit is
still not operating properly, there may be a problem with one of the instrument‟s
switching power supplies. The supplies can have two faults, namely no DC output, and
noisy output.
To assist tracing DC Power Supply problems, the wiring used to connect the various
printed circuit assemblies and DC Powered components and the associated test points on
the relay PCA follow a standard color-coding scheme as defined in the following table.
Table 12-6: DC Power Test Point and Wiring Color Codes
NAME TEST POINT# COLOR DEFINITION
DGND
1
Black Digital ground
+5V
2
Red
AGND
3
Green Analog ground
+15V
4
Blue
-15V
5
Yellow
+12R
6
Purple 12 V return
(ground) line
+12V
7
Orange
TP1 TP2 TP3 TP4 TP5 TP6 TP7
DGND +5V AGND +15V -15V +12R 12V
Figure 12-4: Location of DC Power Test Points on Relay PCA
A voltmeter should be used to verify that the DC voltages are correct per the values in
the table below, and an oscilloscope, in AC mode, with band limiting turned on, can be
used to evaluate if the supplies are producing excessive noise (> 100 mV p-p).
06858E DCN7057