Teledyne M300E Carbon Monoxide Alarm User Manual


 
Troubleshooting & Repair Teledyne API – Technical Manual - Model 300E Family CO Analyzers
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13.1.4.3. Relay Board Status LED’s
There are eight LED’s located on the Relay Board. The most important of which is D1, which indicates the
health of the I
2
C bus. If D1 is blinking the other faults following LED’s can be used in conjunction with DIAG
menu signal I/O to identify hardware failures of the relays and switches on the relay (see Section 13.1.3 and
Appendix D).
Table 13-4:
I
2
C Status LED Failure Indications
LED FUNCTION FAULT STATUS INDICATED FAILURE(S)
D1
(Red)
I
2
C bus Health
(Watch Dog
Circuit)
Continuously ON
or
Continuously OFF
Failed/Halted CPU
Faulty Motherboard, Keyboard or Relay Board
Faulty Connectors/Wiring between Motherboard,
Keyboard or Relay Board
Failed/Faulty +5 VDC Power Supply (PS1)
STATUS LED’s
DC VOLTAGE TEST
POINTS
RELAY PCA
PN 04135
Figure 13-5: Relay Board Status LEDs
04288D DCN5752