Green - On, Red - Fast Blink, Yellow - Fast Blink; Figure 5. Ec-Fx-Nh3 Detector Components - Honeywell EC-FX-NH3 Instruction And Installation Manual

OPERATOR MANUAL
Green — ON, Red — Fast Blink, Yellow — Fast Blink
4/20 mA loop test failed the 22 mA high extremity. Check output impedance
and ensure it is between 10Ω and 700Ω referenced to ground. In addition,
ensure power supply voltage is within specified operating range.

Figure 5. EC-FX-NH3 Detector Components

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