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Adjustment Instructions for Capacitive Sensors

Adjusting Discrete Capacitive Sensors
Adjusting Analog Capactive Sensors

Adjusting Discrete Capacitive Sensors

Capacitive sensors can be adjusted to a variety of materials and filling situations. In general we have two standards operations for adjusting a sensor to its environment.

Adjusting a sensor to a full condition means that the sensor will only detect an object when that object has fully entered the sensor's field. This is useful if there are other objects in the sensor's field that you want to ignore or if you want to ignore a build-up of product that sticks to the sensor like flour, chocolate, or hot-melt glue. This setting is the most accurate setting for detecting material because it will prevent false detections of products.

Adjusting a sensor to an empty condition means that the sensor will detect ANY object that enters the sensor's field. This can be useful for detecting objects at a distance or for early leak detection. This setting will make the sensor the most sensitive for its current mounting position. Beware that ANY object will make the sensor detect and that powder/liquid residue left on the sensor after detection will cause the sensor to remain on.

"Full Adjustment" Instructions:

Locate the sensitivity adjustment potentiometer on the back or on the side of the sensor (for units with a separate amplifier the sensitivity adjustment screw will be on the amplifier. This can be recessed under a plastic or metal screw. Remove the protective screw to adjust the sensor).
Reset the sensor's sensitivity by turning the potentiometer counter-clockwise 20 full turns, or until the sensor no longer sees the product.
Fully immerse the sensor into the product to be detected.
Adjust the sensor to the product to be detected by turning the potentiometer clockwise until the sensor just sees the product.
Add 1/4 turn for safety by turning the potentiometer a further 90 degrees clockwise.

"Empty Adjustment" Instructions:

Locate the sensitivity adjustment potentiometer on the back or on the side of the sensor (for units with a separate amplifier the sensitivity adjustment screw will be on the amplifier. This can be recessed under a plastic or metal screw. Remove the protective screw to adjust the sensor).
Empty your tank of any foreign product.
Find the switching point by turning the potentiometer clockwise 20 full turns or until the sensor's LED turns ON (yellow).
Adjust the sensor to the "empty" environment by turning the potentiometer counter-clockwise until the sensor just turns off.
Add 1/4 turn for safety by turning the potentiometer a further 90 degrees counter-clockwise.

Rechner has a 20-turn trim pot with no mechanical stop. If you find that a full setting is not sensitive enough or that an empty setting is too sensitive then you can find the middle ground for your application by counting the turns between an empty setting off and a full setting on and then adjusting the sensor halfway between the two.

Adjustment Instructions for Analog Capacitive Sensors

Overview

Cylindrical Analog Capacitive sensors detect dielectric material and change the analog output more when an increasing amount of dielectric material is present.

If you have a 4 to 20 mA (IL4) output sensor then the default output when the active area of the sensor is only exposed to air will be 4 mA. As you increase the amount of material in the sensors detection field, the output will increase towards 20 mA.

LED Color

Analog sensors have a 2 color LED. The LED will either be green or orange (amber) when the sensor is powered on.

The Amber LED indicates that the sensor's output is outside of the useable range. On an IL4 sensor this would indicate that not enough material is present and the output will be at the minimum 4 mA. Alternatively, if there is enough material present to fully saturated the sensor's field the output will be at the maximum 20 mA.
The Green LED indicates that the sensor's output is inside of the useable range. On an IL4 sensor this would indicate that the sensor is outputting a signal between 4 mA and 20 mA.

Adjusting a 4 to 20 mA (IL4) sensor

Turning the potentiometer clockwise will make it so that the sensor is more sensitive and therefore requires less material to be in the sensing field for it to be saturated and reach the maximum 20 mA output.
Turning the potentiometer counter-clockwise will make it so that the sensor is less sensitive and therefore requires more material to be in the sensing field for it to be saturated and reach the maximum 20 mA output.
Please note that not all materials have a high enough dielectric constant or density to fully saturate the sensor's field. In cases with these types of materials the actual usable output signal will only vary between 4 mA and for example 14 mA for a thin piece of cardboard.

An IL4 can always output a 4 mA signal. It can only output 20 mA when enough material is inserted into the sensor field and the sensor's potentiometer is adjusted clockwise enough to make the sensor sensitive enough.

Adjusting a 20 to 4 mA (IL20) sensor

Turning the potentiometer clockwise will make it so that the sensor is more sensitive and therefore requires less material to be in the sensing field for it to be saturated and reach the minimum 4 mA output.
Turning the potentiometer counter-clockwise will make it so that the sensor is less sensitive and therefore requires more material to be in the sensing field for it to be saturated and reach the minimum 4 mA output.
Please note that not all materials have a high enough dielectric constant or density to fully saturate the sensor's field. In cases with these types of materials the actual usable output signal will only vary between 20 mA and for example 10 mA for a thin piece of cardboard.

An IL20 can always output a 20 mA signal. It can only output 4 mA when enough material is inserted into the sensor field and the sensor's potentiometer is adjusted clockwise enough to make the sensor sensitive enough.

Adjusting a 0 to 20 mA (IL0) sensor

Turning the potentiometer clockwise will make it so that the sensor is more sensitive and therefore requires less material to be in the sensing field for it to be saturated and reach the maximum 20 mA output.
Turning the potentiometer counter-clockwise will make it so that the sensor is less sensitive and therefore requires more material to be in the sensing field for it to be saturated and reach the maximum 20 mA output.
Please note that not all materials have a high enough dielectric constant or density to fully saturate the sensor's field. In cases with these types of materials the actual usable output signal will only vary between 0 mA and for example 12 mA for a thin piece of cardboard.

An IL0 can always output a 0 mA signal. It can only output 20 mA when enough material is inserted into the sensor field and the sensor's potentiometer is adjusted clockwise enough to make the sensor sensitive enough.