Bonner Q45U Ultrasonic Sensor in Practical Use

When programming the first limit, there is a 2-minute timeout, after which the programming mode will automatically exit, and the previous limit will remain unchanged. There is no timeout limit between the first and second limits.

Press and hold the button for more than 2 seconds at any time to cancel programming and restore the original window.

6.2 Remote Programming

The yellow wire (remote teaching input) can be used for external switch or PLC contact control programming. Apply a DC voltage of+5~24V to the yellow line (relative to the blue line 0V) for a duration that conforms to the timing diagram:

Enter programming: Apply high level for ≥ 2 seconds (similar to long pressing a button).

Set limit: Apply high level for less than 2 seconds (similar to short pressing a button).

Remote programming function and button programming are mutually exclusive: when using remote, buttons are disabled; When using buttons, remote input is ignored.

6.3 Visual feedback during programming process

The 5-segment LED "moving point" indicator displays the relative position of the target between 100mm and 1500mm.

The flashing in the first paragraph indicates that the target is below the near limit (too close to the sensor).

The flashing in the fifth paragraph indicates that the target is greater than 1400mm (beyond the recommended far limit range, but still within the detection range, with only a decrease in linearity).

If the target exceeds 1500mm, stable echoes may not be obtained.

Simulation output characteristics and load calculation

7.1 Voltage output (black line)

Range: 0~10V DC, maximum output current of 10mA (i.e. minimum load resistance of 1k Ω).

Resolution: 2mV (12 bit D/A conversion).

Low output impedance, can be directly connected to PLC analog input.

Calculation formula (assuming proportional slope, window near limit N, far limit F):

V_out=(Target Distance - N)/(F-N) × 10V

When the target is ≤ N, V_out = 0V； When the target is ≥ F, V_out = 10V。

7.2 Current output (white line)

Range: 4~20mA, load impedance 1~500 Ω.

Resolution: 3 μ A.

4-20mA is suitable for long-distance transmission (up to hundreds of meters) and is not easily affected by electromagnetic interference.

Calculation formula:

I-out=4mA+(target distance - N)/(F-N) × 16mA

Attention: The current output is PNP source current, which is provided by the sensor. The load must be connected between the output line (white line) and the power ground (blue line). The load impedance cannot exceed 500 Ω. If it exceeds 500 Ω, the output voltage will rise beyond the capacity of the internal constant current source of the sensor, resulting in output distortion or protection action. The minimum load impedance of 1 Ω (without considering wire resistance) is sufficient, but usually a 250 Ω resistor is used to convert it to 1-5V for PLC reading.

7.3 Output fault indication

The flashing green LED indicates a current output fault, usually caused by an open circuit of the white line (not connected to the load or disconnected line) leading to interruption of the current circuit. Voltage output faults (such as short circuit overload) will not flash the LED, but the output will enter a protective state.

On site debugging and troubleshooting

8.1 Sensor has no output or fixed output

Possible causes and solutions for the phenomenon

The green LED does not light up. If the power is not connected or reversed, check the brown (+) and blue (-) polarities; Measure the power supply voltage of 15-24V DC

The red LED is constantly off and no echo has been received. Check if there are any obstacles in front of the sensor; Whether the target distance exceeds the range; Is the target surface made of strong sound-absorbing materials (such as sponge or fabric)

The red LED flashes but the output remains unchanged. The window limit programming is incorrect. Re open the TEACH window to ensure that the near and far limit settings are reasonable

Output always in minimum/maximum echo loss mode (DIP3 ON) and no echo check DIP4 setting; Confirm that the target is within the window

8.2 Output nonlinearity or jumping

Response speed too fast: Reducing the response speed (increasing the average cycle) can smooth out the output.

Uneven or irregular target surface: Ultrasonic sensors measure the acoustic center of the target area, and irregular surfaces may cause point like reflections. At this point, the average cycle should be increased or a fixed reflector plate should be used.

Electrical noise: The sensor power supply is shared with high-power devices such as frequency converters, resulting in excessive power ripple. Isolation power supply or installation of filters should be used.

8.3 Large temperature drift

Confirm if the sensor is within the temperature compensation range. If the ambient temperature exceeds -25~70 ℃, linearity may be lost.

Long term direct sunlight or proximity to heat sources can cause local temperatures to be higher than ambient temperatures, affecting compensation accuracy. Sunshades should be installed or isolated from heat sources.

8.4 Misprogramming

If the programming mode is accidentally entered and no limit is set, the sensor will timeout and exit after 2 minutes, retaining the original window. But if the button is pressed incorrectly and the target position is incorrect, it may change the window. The solution is to reset TEACH to the correct window limit.