Q: How can we prevent a diffuse reflection photoelectric sensor from falsely detecting background objects outside of its sensing range?
A: As a first step, we should verify if the falsely detected background has a "high-brightness reflective" property.

High-brightness reflective background objects can interfere with the operation of diffuse reflection photoelectric sensors. They cause false reflections, leading to incorrect sensor readings. Moreover, high-brightness reflective backgrounds can also interfere with both diffuse reflection and background suppression photoelectric sensors to some extent.

 

LANBO Picks “Lanbao VCSEL Photoelectric sensor”

 

PSE-PM1-V series Polarized reflection Photoelectric sensor	PSE-YC-V series Background suppression Photoelectric sensor
Sensing distance: 1m (non-adjustable) Output mode: NPN/PNP NO/NC Light source: VCSEL light source Spot size: approximately 3mm @ 50cm	Sensing distance: 15cm (adjustable) Output mode: NPN/PNP NO/NC Light source: VCSEL light source Spot size: <3mm @ 15cm

 

Q:Determination of frequency and sensor selection based on rotational speed

A:Frequency can be calculated using the following formula: f(frequency) Hz = RPM / 60s * number of teeth.

•Sensor selection should consider both the calculated frequency and the gear's tooth pitch.

Frequency-Time Reference Chart：

Frequency	Cycle (response time)
1Hz	1S
1000Hz	1ms
500Hz	2ms
100Hz	10ms

Nominal Frequency:

For inductive and capacitive sensors, the target gear should be positioned at 1/2Sn (ensuring that the distance between each tooth is ≤ 1/2Sn). Use a frequency test fixture to test and record the frequency value of 1 cycle using an oscilloscope (for accuracy, record the frequency of 5 cycles and then calculate the average). It should meet the requirements of 1.17 (if the nominal operating distance (Sa) of the proximity switch is less than 10mm, the turntable should have at least 10 targets; if the nominal operating distance is greater than 10mm, the turntable should have at least 6 targets).

  LANBO Picks “High frequency inductive sensor   &  Gear speed inductive sensor”

 

M12/M18/M30 Frequency inductive sensor	M12 Gear speed measurement series inductive sensor	M18 Gear speed measurement series inductive sensor
Sensing distance：2mm、4mm、5mm、8mm Switching frequency [F]：1500Hz、2000Hz、 4000Hz、3000Hz 10-30VDC NPN/PNP NO/NC	Protection degree IP67 (IEC).   Frequency up to 25KHz.   Long life and high reliability.   Sensing distance 2mm	M18 metal cylindrical type, NPN/PNP output Detection distance: 2mm Protection degree IP67 (IEC) Frequency up to 25KHz

 

Q:When a pipeline level sensor is used to detect the liquid level in a hose, the sensing is unstable. What should I do?

A:First, check if there is a half-sided adhesive label on the hose. If only half of the hose is labeled, it will cause a difference in dielectric constant, resulting in unstable sensing as the hose rotates.

Dielectric Constant:
The dielectric constant reflects the relative ability of a dielectric material to store electrostatic energy in an electric field. For dielectric materials, the lower the relative dielectric constant, the better the insulation.

Example: Water has a dielectric constant of 80, while plastics typically have a dielectric constant between 3 and 5. The dielectric constant reflects a material's polarization in an electric field. A higher dielectric constant indicates a stronger response to an electric field.

LANBO Picks “High frequency inductive sensor   &  Gear speed inductive sensor”

 

Frequency enhanced Capactive Sensor CE16 series

Sensing distance：6mm
Can detect metal and non-metal material objects, more widely used.
Response frequency up to 100Hz.
Fast and accurate sensitivity adjustment with multi-turn potentiometer.

 

 

 

 

Q:How to select sensors for particle feed detection in the livestock industry?

A:The presence of gaps between individual particles in granular feed reduces the effective contact area with the sensing surface, resulting in lower dielectric properties compared to powdered feed.

Note: Pay attention to the moisture content of the feed during sensor operation. Excessive moisture in the feed can lead to long-term adhesion to the sensor surface, causing the sensor to remain in a constant on state.

CQ32XS series Capacitive sensor	CR30X series Capacitive sensor
Sensing distance: 15mm (adjustable) Housing size: φ32*80 mm Wiring:AC 20…250 VAC relay output Housing material:PBT Connection: 2m PVC Cable	Sensing distance: 15mm, 25mm Mounting: Flush/ Non-flush Housing size: 30mm diameter Housing material: Nickel-copper alloy/ plastic PBT Output: NPN,PNP, DC 3 /4 wires Output indication:Yellow LED Connection: 2m PVC Cable/ M12 4-pin connector