Frequently Asked Question
Tilt/Acceleration switches are often connected to a PLC or to a relay for controlling the safety of a machine or any other applications. Want to know how it works exactly? Please read here.
The switch output can be made by using a PNP/NPN transistor, please read "Working of Transistor as a Switch" to learn more details.
Our first generation tilt switches can withstand a max load current of 150mA continuously and 250mA for max. 10 seconds. For a 2-axes tilt switch, there are 2 independent switching outputs, each output can withstand 150mA but not at the same time. From our tests and feedbacks from the market, we know this model is not 100% robust when large current is used. Therefore we decided to redesign this model.
SmartFETs are introduced to the new generation tilt switches, which ensures that our sensor can withstand 150mA for both outputs simultaneously.
It is better not to share the Sensor GND with any load GND over longer wiring when this load GND carries e.g. motor currents and may be flagged as "dirty". Consider a star gnd configuration to minimize hard to diagnose behavior.
NPN sensors need a pull-up resistor, which should be connected between the output and the Vcc For testing the sensor, you can use a 5K resistance as the load. If the resistor is missing, you will read a wrong output.
Can I connect two PNP outputs to the same load?
Our sensors typically have two independent PNP outputs. Connecting both outputs directly to the same load effectively creates an OR function: the load is activated when either output is active.
However, directly connecting the outputs in parallel can cause problems, particularly with SIL1 switches. These sensors monitor the actual output level and compare it with the expected output state. If one output is active, its voltage can feed back into the other output, potentially interfering with this diagnostic function and causing an error.
If both outputs need to control the same load, always install an external isolation diode between each output and the load. This prevents one output from feeding voltage back into the other and ensures that the two outputs remain electrically isolated.
e.g.
Reference:
https://www.electronicshub.org/mosfet-as-a-switch/