The Presec system displays 4 levels of filter cartridge saturation via 3 relays connected to 3 LEDs:
Stable green light (a):
- The system is operational; the cartridge is OK.
Yellow pulsating light (b):
- Warning: the cartridge is running out and should be replaced soon.
Red pulsating light (c):
- Alarm; the cartridge is used up and must be replaced immediately.
Red pulsating light (c):
- Alarm; filter cartridge missing or filter system interrupted; compressor switches off and cannot be restarted until a new cartridge is inserted or the cause of the alarm is identified.
When the yellow light (b) is pulsing, the green light (a) will still be on, as the filter cartridge is not yet fully saturated.
If no LEDs are lit it means that the PRESEC system has no power supply or that an electrical fault has occurred.




