EVCO c-pro nano NAV - Manual (Page 30)

C-PRO NANO AND MICRO NAV APPLICATION MANUAL
Page 30
6.10 DELTA alarms
These alarms allow to check the correct machine functioning, monitoring the respect of several
temperature values with the compressor on. The alarm condition is delayed on start-up of the
compressor by a time (tDEL parameter, default 10sec).
6.10.1 DELTA 1 alarm (summer functioning mode only)
The alarm is active in the following conditions:
- If the difference between the fresh water input temperature AI1 and the output temperature
AI2 is greater than a value (dAL1 parameter)
- If the fresh water input temperature is lower than that set (EAL1 parameter)
The alarm deactivates if the difference drops back by a differential of 2 degrees.
6.10.2 DELTA 2 alarm (summer functioning mode only)
The alarm is active in the following conditions:
- If the difference between the fresh water input temperature AI1 and the output temperature
AI2 is lower than a value (dAL2 parameter)
The alarm deactivates if the difference drops back by a differential of 2 degrees.
6.10.3 DELTA 3 alarm (winter functioning mode only)
The alarm is active in the following conditions:
- If the difference between the fresh water output temperature AI2 and the input temperature
AI1 is greater than a value (dAL3 parameter)
- If the fresh water input temperature is higher than that a set (EAL3 parameter)
The alarm deactivates if the difference drops back by a differential of 2 degrees.
6.10.4 DELTA 4 alarm (winter functioning mode only)
The alarm is active in the following conditions:
- If the difference between the fresh water input temperature AI1 and that of the SETH set-
point is greater than a value (dAL4 parameter)
- If this difference remains higher for a time (parameter tAL4)
The alarm deactivates if the difference drops back by a differential of 2 degrees.
6.11 Phase sequence alarm
To check the correct connection of the compressor motor phases, the fresh water temperature
variation between input and output is measured after a time sufficient to appreciate offset (tSF
parameter, default 100sec). The formula of the offset is:
|AI1 – AI2| < ∆Tmin
where ∆Tmin can be set via parameter dSF.
The alarm intervention (with manual restore) switches the compressor and the salt water pump off.