Leakwise ID-220 SERIES User Manual page 33

The SLC-220 processor is responsible for status/warning decision-making based on comparing
the existing sensor signal to the calibration and set point parameters that were programmed by
the user.
For example, "Oil Alarm" will be determined when sensor's signal is more than Water Calibration
minus High Oil Delta set point, and also less than Water Calibration minus Oil Delta set point.
Only one status is possible at a given time.
Calibration parameters Water Calibration and Air Calibration are the basic reference for every
decision-making. These two parameters should be entered once after seeing the measured
sensor signal when the sensor is dry (Air Calibration) and when the sensor is floating in clean site
water (Water Calibration).
All calibration parameters are positive numbers, in µA.
The following set points are in reference to Water Calibration:
•
Over range Delta: Sensor signal above Water Calibration + Over Range Delta is
abnormal and indicates that the sensor either went under water or failed.
•
Oil Delta: Sensor signal below Water Calibration – Oil Delta means oil detection. This is
the first oil alarm setting, for relatively thin oil layer detection.
•
High oil Delta: Sensor signal below Water Calibration – High Oil Delta means high-oil
detection. This is the second oil alarm setting, for relatively thick oil layer detection.
Air Delta is in reference to Air Calibration. This parameter ensures that when the sensor is not
floating on water or on oil, the indicated status will be AIR even if the sensor is not 100% dry.
Under Range Set Point is an absolute parameter. It defines a minimum signal which is normally
expected from the sensor. If sensor signal is lower than this value, it the sensor failed.
In addition to the above parameters, there is a Hysteresis parameter that influences each
comparison of sensor's signal to the other parameters and calibration points. The default value is
5 µA, and it adds a hysteresis of ±5 µA around each crossing point between two adjacent status
decisions.
SLC-220 User Guide Rev 2.0
33
June 2018