Using The Internal Electronic Status Leds; Cpu Status Indicator; Power Distribution Board Status Leds; C Bus Watchdog Status Leds - Teledyne T750 User Manual

U I
8.3.
SING THE NTERNAL
Several LEDs are located inside the instrument to assist in determining if the calibrators
2
CPU, I C bus and Power distribution board are functioning properly.
CPU S
TATUS
DS5, a red LED, that is located on upper portion of the motherboard, just to the right of the
CPU board, flashes when the CPU is running the main program loop. After power-up,
approximately 30 – 60 seconds, DS5 should flash on and off. If characters are written to
the Input and Control Panel display but DS5 does not flash then the program files have
become corrupted, contact Technical Support because it may be possible to recover
operation of the calibrator. If after 30 – 60 seconds neither DS5 is flashing and nothing has
been written to the Input and Control Panel display then the CPU is bad and must be
replaced.
P
OWER
There are sixteen status LEDs on the power distribution board, Described in Table 8-4 and
Table 8-5, and depicted in Figure 8-2. Not all are used on this model.
I 2

C Bus Watchdog Status LEDs

The most important is D1 (see Figure 8-2), which indicates the health of the I

Table 8-4. Power Distribution Board Watchdog LED Failure Indications

LED Function
D1 I 2 C bus Health
(Red) (Watchdog Circuit)
If D1 is blinking, then the other LEDs can be used in conjunction with the
Utilities>Diagnostics>Analog Inputs menu to identify hardware failures of the relays and
switches on the board.
138
E S
LECTRONIC
I
NDICATOR

Figure 8-1. CPU Status Indicator

D B S
ISTRIBUTION OARD
Fault Status
Continuously ON
or
Continuously OFF
LED
TATUS S
LED
TATUS S
Indicated Failure(s)
Failed/Halted CPU
Faulty Motherboard or Power distribution board
Faulty Connectors/Wiring between Motherboard or
Power distribution board
Failed/Faulty +5 VDC Power Supply (PS1)
2 C bus.
083730750B DCN8606