Limit switch explained in everyday language

AI Thread Summary
A limit switch is a device that activates or modifies a control function when a moving part reaches a predetermined position. It can be mechanical, using an arm that is triggered when compressed, or optical, where a flag interrupts a light beam to signal the switch. Limit switches are essential in systems driven by motors, as they indicate when the motion range has been reached, preventing damage. They are commonly found in various electro-mechanical mechanisms and are often integrated with software for monitoring. Understanding limit switches is crucial for managing equipment that involves significant movement.
Stanley_Smith
Messages
16
Reaction score
0
Can someone explain to me how limit switch works in everday language, I got some sources that are too technical.

Thank you,
 
Engineering news on Phys.org
Stanley_Smith said:
...I got some sources that are too technical.

Thank you,

Share the sources and maybe we can help.

Regards

Don
 
http://www.ab.com/sensors/products/limit_switches/

I find it's not very easy to comprehend 100% the whole article
 
Last edited by a moderator:
The real difference between a "limit" switch and any other switch is that it is connected to a control function.
In other words activation starts, stops or otherwise modifies some process.

Your link is to a particular device that can be used for this function.
There are other types using light, magnetism, pressure ect.
You could take the light switch off your wall and use it as a limit switch.
 
It is simply a switch which is activated by something "hitting" it. There are many different types of limit switches.

If you have a mechanism driven by a motor, it is very helpful to know when you have reached the end of your motion range. You can to this with a mechanical switch which is simply a micro switch with a arm attached. When your moving part compresses the arm the switch flips and turns off your motor (That is not the actual mechanism, but essentially what happens).

There are also optical limit switches, for these you attach a "flag" to your moving part, the flag (a tab of metal) passes through the optical switch it blocks passage of light (the source is a LED) and trips the switch.

Limit switches are on virtually all electro-mechanical mechanisms which involve movement of significantly massive parts. In modern equipment they are usually monitored by the software which is controlling the motion.
 
Very basic question. Consider a 3-terminal device with terminals say A,B,C. Kirchhoff Current Law (KCL) and Kirchhoff Voltage Law (KVL) establish two relationships between the 3 currents entering the terminals and the 3 terminal's voltage pairs respectively. So we have 2 equations in 6 unknowns. To proceed further we need two more (independent) equations in order to solve the circuit the 3-terminal device is connected to (basically one treats such a device as an unbalanced two-port...
suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts with terminal 1 being - (negative) and terminal 2 being + (positive). you connect the voltmeter to terminal A2 and to terminal B1. does it read any voltage? can - of one capacitor discharge + of the...
Back
Top