Views: 325 Author: China Micro Switch Manufacturer Publish Time: 2020-08-17 Origin: https://www.unionwells.com/
Custom Limit Switch Wiring Tips
In the field of electrical engineering, limit switches are switches whose operations are managed by dynamic parts of a machine or some other object. Limit switches have gained widespread acceptance for some time now. For instance, they are known to be used as control systems for machine parts, security interlocks, or as a counter for objects that are going through a particular place.
These are electromechanical devices that comprises one actuator and several contacts. The actuator has a mechanical linkage to the contacts. Anytime an object is in close proximity with the actuator, the contact is operated by the device to establish an electrical contact or otherwise.
Application of limit switches
Like we have stated, limit switches have gained uses in several industries around the world today. They are more suitable for most applications and environments. The reason behind their popularity is because they are quite easy to install, are extremely rugged, and can be heavily relied upon when they have been installed. They are mostly used for determining the absence, presence, positioning, passing, and end of movement of any object. Their very first usage was in defining the last part of an object passage, which was what gave rise to the name Limit Switch.
Standard based limit switches happen to be applied as control components for industries. They are bound to comprise different operator types, which includes roller plunger, lever, as well as whisker. These switches could be explicitly controlled due to the movement of an operating lever. Proximity indication as to how close it is mounted to a machine part can be handled by a reed switch. Proximity switches function as a result of the disturbance created by the capacitance or magnetic field that will be created by an electromagnet.
In rare instances, one final operation mechanism like a lamp will be controlled by the industry based limit switch contacts.
How to wiring a limit switch
Even with the wide area of application of limit switches, you still have to observe certain things to ensure for a safe wiring. Here are some of the tips you need to have at the back of your mind when you are wiring a limit switch.
• If you intend to use the limit switch as some form of safety mechanism to prevent accidents that could result to fatalities, then employ a switch that has direct opening system, apply the contacts for a normally closed mode with forced release mechanism, and let the switch remain in its direct opening mode status.
• Make sure the power source has been turned off because you commence the wiring. That is to prevent you from experiencing any electric shock.
• Ensure the electrical load is always beneath the stipulated value.
• Do not forget to assess the switch to know if it is actually working after you must have finished the installation.
• Try not to touch the charged terminals of the limit switch when current has passed through it. It could result to an electric shock.
• If the limit switch comes with a ground terminal, ensure that terminal is linked to ground wire.
• Refrain from disassembling the limit when current is passing through it. So you do not risk getting shocked in the process.
• How long the limit switch will last will be determined by how it is when it is switched. Before you make use of the limit, ensure it is adequately tested under the usual working conditions. Be sure the switch can permit as many switching operations as possible within the said range. That is because if you end up working with a switch that is in a bad state, a negative things are bound to happen to the switch.
• Every wire that is connected to a limit switch should be spaced as much as possible to avoid any accidental shorting.
• Some load types have a considerable range between their inrushing current and normal current. Ensure the inrush current falls within the permitted value. The higher the value of inrush current, the higher the likelihood if the contacts coming together. That could lead to further damages in the limit switch.
The actual wiring of a limit switch
You have to be very careful when you are wiring a limit switch. The terminals have to be appropriately wired for it to function correctly. If you do not wire the terminals of the limit switch the way it should be, it will not work. Worse still, you can end up damaging the limit with such incorrect wiring. That is why we began this section by emphasizing utmost caution when wiring your limit switch. While that cannot be overemphasized, let’s look at how it is really done.
• Do not alter the actuator so its working characteristics will not be affected as well.
• Do not use grease or any other lubricant on the parts of the actuator that is moving.
• The switch should be mounted and secured with the screws thoroughly fastened as expected.
• Wire the switch in such a way that the conduit opening would be devoid of any form of impurities.
• If you are making use of bonding or glue, ensure it does not touch any of the movable parts.
• Avoid imposing any vibrations or shock on the actuator anytime it is pressed completely.
• Take precautionary steps to ensure that no liquid can finds its way inside the limit switch after your installation.
• A couple of models do allow head directional changes. When you are doing such changes, you must ensure that the head is devoid of any foreign objects.
Limit switches are very sensitive devices when they are in operation, so they have to be treated as such. Unlike most other switches, they can easily disappoint you if they are not maintained as expected. A lot of safety wiring tips have been reeled out in this post, if you adhere to those, your limit switch will not only work well, but it will equally last the test of time.