P/N 06160D DCN6409 Teledyne API Model 465M O3 Monitor Instruction Manual - Page 66
10.2. Troubleshooting Using Front Panel Status

LED’s or Status Outputs

The M465M has 4 front-panel status LED’s that reflect the current operating status of the
monitor, and indicate fault conditions. There are also four relay Status Outputs on the
rear panel (or internally in the NEMA configuration) that also reflect the state of these
status LED’s. See Section 4.5.3 for more information on the Status Outputs.
Table 10-1: Status LED/Output Definitions
Status
Output # Status LED
Label Normal
Operating
State
Triggers Critical
Warning?
1 Sensor OK On Reference < 125.0 mV
Reference > 1230.0 mV – 0.5 Wt% Yes
2 Invalid Reading Off O3 Concentration < F.S. Range
O3 Concentration > F.S. Range No
3 Check Lamp Off Reference < 250.0 mV No
4 Pneumatic
Error Off Pressure < 9.0 psia
Pressure > 18.0 psia
Flow < 500 cc/min*
No
*If Flow Switch installed