There are several different types of medium voltage earthing systems. These systems can be differentiated by using the neutral point connection method. They are different in the way that they operate and each of them has its own pros and cons. These earthing systems in medium voltage include the likes of:

The functioning of each differs from the other. They also have various applications. Let’s have a look at each system at a time:

In this one, there is no electrical connection between the earth and the neutral point except for the devices that are used for measurement or protection. There is high impedance inserted between the earth and the neutral point. There is no switching on occurrence of the first insulation fault. It is therefore important to carry out permanent insulation monitoring, show the first insulation fault and locate and clear the first insulation fault.

Pros and cons: The advantage of using this one is that it provides services by tripping only when the second fault occurs which is subject to the capacity of the network not leading to a high earth fault current which would be dangerous for people when the first fault occurs. It has its demerits. There is the risk of high internal over-voltages. Insulation monitoring is also compulsory as well as the presence of maintenance personnel who will be monitoring and locating the first fault during use.

It is also known as direct earthing. It has a connection between the earth and the neutral point. Upon first insulation fault occurrence compulsory switching must be done. It is significantly different from the above mentioned unearthed neutral.

Pros and cons: This system reduces risk of over-voltage occurring and also authorizes the use of equipment with a normal phase to earth insulating level. On the other hand, there is mandatory tripping upon occurrence of the first fault. The touch voltages developed are very high and this poses a high risk for the personnel while the fault lasts. Differential protection devices must be used so that the clearance time of the fault is as short as possible.

This system requires a resistor to be inserted between the neutral point and the earth. It is also known as limiting resistance earthing. Their operating technique is quite straightforward. Switching must be done upon the occurrence of the first fault.

Explosion proof fixtures are a necessity for environments which output potentially explosive or flammable fumes, produce dust of dirt in the air, or similar situations in which a gas could enter the fixture and cause damage to the light or well-being of the facility.

If you are currently running or working with a facility which requires these explosion proof light fixtures, the list of 3 must-haves below will clear the air and hopefully set you on the right track to ensuring you have the proper setup and design.

First on the list, we are going to talk about the actual technology within the fixture and why it is so important.

While a big part of vapor proof lights is the actual fixture and its design, we think the luminaire within the fixture is equally as important.

We simply can’t recommend any other technology other than LED because we truly believe in it. To give you a little bit of insight on industrial LEDs, here are some of the reasons why companies of all sorts are converting to LED:

As you can see, just from these three main benefits that all sorts of facilities are realizing can really be game changing in terms of savings.

For these reasons (and more), we thought it was a must to have it first on the list.

Interested in learning more? Find Class 1 Div 2. For this reason, we suggest you always inquire with a reputable and knowledgeable company that offers and deals with explosion proof lighting when inquiring about your lighting project.

If you can’t find a reputable company to ask your questions, just LED explosion proofs offer the long-term solution is clear.

Especially when you consider in rebates, your initial upfront investment can be reduced greatly. While these rebates do vary from place to place, they are most often available when you buy DLC qualified fixtures. Not only are DLC qualified fixtures going to make you more eligible for rebates through your utility company, but they also provide other benefits. The biggest benefit of buying DLC qualified lights is they have ben tried and tested and, in most cases, do what they claim. In a busy world of lighting, not all products do exactly what they say. This is most common when a light is not qualified by something like the DLC.

Our main advice is this; to get the best value buy only DLC qualified fixtures. If you don’t, you may actually end up spending more upfront (by not getting any rebates) as well as more energy usage overtime, due to a less efficient build.

Another major cost saver can come through retrofitting. The only time you can retrofit is if your fixture is still functional and can fit a LED retrofit in it. If you do not match these requirements, then a full replacement will (typically) be required.

If you can, we suggest you retrofit. It saves money in two ways: retrofit kits are cheaper than full fixture replacements and the cost to retrofit is typically less time consuming and thus, less expensive.

In Summary

We know that a sensitive environment can be stressful to deal with, especially when it comes to the lighting system and the safety of the facility.

The above 3 must-haves are just the beginning, and each situation can vary greatly. As always, we suggest you consult with some lighting professionals to truly discover what you may require for your facility and operations.

We all know that lowering the thermostat a degree or two in the winter will also lower our energy bills, and that turning off the lights when you leave a room conserves energy. There's a lot more you can do to protect your wallet from high utility bills. The U.S. Department of Energy shares eight ways to help you get more bang for your energy buck.