10 Things You Must Know Before Purchasing Electrical Conduit Pipe

We have received many letters from readers asking some questions in the last couple of weeks, some of them look like ‘fresher’, But some of their questions surprised us a little bit. In addition, we have also done research online to write this post, hoping to help readers or new buyers.

The electrical conduit is designed to protect wires because the wire is fragile, and there are will cause safety risks after damage. However, there are different sizes and names for different countries and markets, which makes it easy to confuse especially new buyers. In addition, the industry itself has a lot of professional vocabulary and certification standards. For new buyers, We strongly recommended you find a reliable supplier who can avoid many problems. For example, Ctube.

One more thing, we wrote a post for talked about conduit pipe & fittings type on the market last month. You can read the post here for the type of conduit & fittings and how it works.

Ok, let’s get started.

1. What Are the Effects of Sunlight on PVC?

electrical Conduit Pipe

Sunlight PVC pipe used for outdoor project purposes in general.

Well, there are many outdoor use scenarios, such as you need to run wires to your tool room, or install solar energy equipment. Because these wires and tubes need to be exposed to sunlight for a long time, and they are attacked by high temperatures, water, dust, and even temperature sharply drops at night, the performance of the wire and tube at low temperatures needs to be considered.

If you use an ordinary PVC electrical conduit, what will happen? The most common problems are yellowing, brittleness, and cracking of your wires tubes. This kind of line tube is usually white in color. Because they are NOT designed to be used as electrical conduits (usually for plumbing water pipes), they cannot protect your electrical wires under long-term exposure conditions.

From the perspective of product manufacturing, general electrical PVC wiring pipes, especially those with UV protection wiring pipes are generally in gray. And It has a different additive formula in the production process between ordinary PVC wiring pipes, so it is far superior to white PVC pipes in terms of UV protection.

In addition, there are differences in low temperature and waterproof performance. Specific data need to refer to the standards of each country. For example, you can check our Schedule 40 PVC pipe product page to get details for this.

2. Can I use white PVC for an electrical conduit?

No, you need to consider the US National Electrical Code requirement for all components of electrical installations need to be approved national test agency. So we do NOT recommend white PVC for electrical wiring pipes.

In addition, electrician wiring pipes are slightly different in formula and manufacturing process compared to water pipes. The thickness and diameter of electrical line pipes have strict industry standards, not just to unify one size. Electrician conduit can prevent overload and high current in an instant, also it has a higher fire rating. We even have low-smoke halogen-free ( LSZH Electrical PVC Conduit ) PVC pipe, the flame retardant grade is highest ( V0 grade fire rating, it will self-extinguished in 5 seconds after the cut off the fire sourcing ), and it can emit less smoke when burned compared with white PVC conduit avoid to release of toxic halogens to increase the survival rate of rescue operations. These are the test standards and content that ordinary drain pipes missing.

So for your safety, we do not recommend you to do this.

3. What is the difference between white PVC and grey PVC?

electrical Conduit Pipe

Firstly, we do not think the color is the first consideration in your purchase decision.

But in fact, color does represent the difference in product application to some extent. For example, the anti-UV conduit pipe we mentioned earlier.

So we take Schedule 40 and Schedule 80 PVC pipes as an example.

These two pipes are just a standard. The most critical parameter is thickness. Schedule 80 is much thicker than Schedule 40 PVC pipe, and Sch 80 pipe is gray or dark gray in general. Sch 40 PVC pipe is white compared with the same period, and the thickness is thinner than Sch 80 PVC pipe.

So it is obvious from the comparison of the two parameters. Schedule 40 PVC pipe can be considered for home improvement or indoor decoration, while Schedule 80 PVC pipe is much stronger, so it can be considered for outdoor projects.

From the manufacturer’s view, PVC was originally a very stable raw material, and its color was white. The gray color is caused by the special formula additives dying in the later period. These additives greatly enhance the high-temperature resistance of PVC and make the current conductivity weaker, so it can withstand Shocking thousands of volts of instantaneous voltages.

Of course, the color is not the standard. The most important thing is to see the body printing of the tube to identify the purpose before buying. It is the most reliable.

4. Does an electrical PVC conduit need to be glued?

electrical Conduit Pipe

Of course. The National Electrical Code requires all of the conduit connections must to be tight. As to the PVC conduit pipes, it means glue.

Using glue to glue electrical pipes is the same principle as we glue other things, and the DIY is not difficult.

As a manufacturer, we do our best to control the tolerance range of each wire pipe size and strive to ensure compliance with relevant international standards, such as UL651. But the actual situation is that in the case of invisible to the naked eye, even on the same production line, there will be certain tolerances for PVC line pipes produced at different periods, which is inevitable.

Then, there will be extremely tiny gaps between the pipe to pipe or fittings, and between the pipe and the fittings. The role of glue is to fill these gaps, so the water, cement, and dust can hardly enter the inside of the pipe through such gaps,

Moreover, the glue itself has the effect of adhesion, which can increase the strength of the joint, and it is not easy to fall off. Of course, the fundamental purpose of doing this is to protect the wires inside the line pipe from being easily affected by these impurities.

Pro Tips,

(1) Professional PVC glue must be used instead of ordinary glue. Because PVC glue has high adhesion strength and resistance to high & low temperatures, water, etc, all of these features not available of ordinary glue;

(2) Glue can be evenly applied to the connecting part of the male connector of the pipe, and the female connector can be applied a little bit. After coating, insert the male head into the female head, insert it in a slightly rotating manner and reach the right position to ensure that the glue is in full contact;

(3) It is best to use a small brush to apply the glue. It does not need to be applied too thickly, just a thin layer, otherwise, the glue will overflow.

(4) PVC glue usually takes 1-2 hours to fix, reaches the ready to use after 24 hours, and reaches the best adhesion strength after 48 hours.

5. How to connect a PVC conduit to an electrical box?

electrical Conduit Pipe

First of all, in addition to the PVC electrical conduit and the electrical box, you also need to prepare an adaptor with locknut and PVC glue.

As for the installation method, so easy. The first step is to glue the pipe to the adaptor, remember to use glue, and your can reference our previous Pro Tips content about glue conduit pipes. The second step is to insert the threaded part of the adaptor into the electrical box, and then lock it with the locknut. Of course, you can also add a little glue to the locknut part, which is more firm and reliable, and it is also the simplest way of waterproofing.

Of course, if your electric box is integrated with fittings, then you can directly apply glue to the wire tube and insert it into the electrical box.

In addition, if the flexible pipe needs to be connected to the electrical box, you just follow the above steps, the only difference is you need to pick up another adaptor used for flexible pipe for the locking part is needed to fix the flex pipe end.

I believe you will know how to connect through the pictures.

6. Why can’t PVC be recycled?

This is an incorrect question because PVC can be recycled, but the recycling cost is too high.

PVC, like other plastics, is often accompanied by many impurities after being eliminated and used, and it needs to be sorted before it can be recycled. The early physical recycling and burning recycling methods have been eliminated. The quality of the plastic materials recycled by the former is not good because it is difficult to sort. The latter is harmful to the environment because many harmful gases are released during the burn of PVC to pollute the environment. Therefore, at present, only chemical recycles methods can be used to do this. Chemical recycles can get higher quality recovery, but the cost is high.

BTW, the recent crazy increase in crude oil prices has greatly affected the prices of plastic raw materials, so recycling is a trend in the future.

Secondly, the quality of recycled PVC is not as good as that of brand new materials. So it can only be used for some low requirement applications, such as shoe soles, agricultural drainage pipes, and so on.

From the electrical PVC pipe industry, recycling has another meaning. What we call Recycling Materials usually means that after the first injection or extrusion, there may be some quality issues that may cause the product to be scrapped. To not waste raw materials, the process of mixing these raw materials back into use is called recycling. It has a different meaning from the recycled raw materials above and can be said to be the raw materials for the second processing.

Of course, what is described above is an ideal situation. If the raw materials are only circulated in the factory, it should be better. Some factories buy this kind of recycled materials and mix them with a certain proportion of brand-new materials, so you can’t distinguish it in appearance, but its physical properties are much different from those made of 100% brand-new materials. This is why Ctube insists on using brand new materials during the 10+ Year production process. It can be said that we have never been complained by customers in this regard.

7. Can I run an Ethernet cable next to electrical?

No, you can’t. NEC general sets a minimum separation of 2 inches between communications and electric power cables. In addition, for security purposes, this is not a best practice.

There are 2 key points here. The first one is that the ethernet cable is a signal wire, and the current is weak, and there is a possibility that the signal will be interfered with by a strong current one. Then the performance of your network signal is unstable, there will be irregular interruptions or high data transmission delays, which will affect your experience.

The second one is the wire generally has a relatively large current and the temperature will be higher. If an accident occurs, the large current may directly cause an instant short circuit of the wire, and at the same time, it will be transmitted to the ethernet cable and affect your terminal equipment (such as routers), resulting in damage to your terminal equipment.

So we suggest that you need to run these two wires separately. Common power wires are installed through one pipe, while ethernet cables are installed through another pipe. And through accessories such as bend, they can be installed from two different positions. which can increase signal stability and safety.

8. How to choose the appropriate PVC pipe?

This is a broad question because we don’t know exactly the purpose of the reader. So we only talk about our area. Yes, that’s an electrical conduit pipe.

Firstly is the material, we think PVC should be a smart choice. As we mentioned before, PVC material, especially the current high-quality raw materials can hold the instantaneous voltage shock of several thousand volts, and it has many advantages such as anti-rust, waterproof, and UV resistance.

Secondly is checking the parameters. Generally, household wires will have cable diameter data, and run the 2-3 ways is in one electrical conduit is no big problem. So you need to pay attention to inner diameter and thickness when buying the wire pipe. Generally speaking, the inner diameter of the purchased wire pipe must be larger than the sum of your wire diameters, and extra space can be reserved for future upgrades or replacements.

Finally, choosing a reliable brand is very important. Brands such as Charlotte Pipe or Carlos are more reliable in the US because they have many years of experience and relevant certification. We suggest that you can buy directly from their official channels or distributors. There are also customers asking whether we can buy on Amazon? We think that Amazon may be more professional in the field of e-commerce, but they do not understand and doing great about quality control of products such as electrical pipe, so we do not recommend buying on an e-commerce website such as Amazon.

9. Does an outdoor electrical wire need to be in a conduit?


As we mentioned before, the wiring runs outdoor, it will not only be exposed to sunlight direct in a long-time, but also will be affected by factors such as low temperature at the night, water, dust, even wild animals.

If the wire is damaged, it will not only waste your time to repair it. Moreover, damaged wires may cause a safety accident, which is dangerous.

Some of our customers also told us that the wires they laid out would not be exposed to sunlight, but we mentioned that there are other reasons. We need to know that the insulation layer of the wire itself is thin, so it has the limited protective ability. So we still recommend installing electrical conduits.

Whether it is directly buried underground or run wires on the ground, you should place them in the wire tube to provide better protection for safety.

10. How to run a conduit around corners?

electrical Conduit Pipe

This question is not difficult to answer, just use the conduit fittings, such as bend or elbow.

We have seen that many construction workers use springs or hot air guns to bend pipes in the actual construction process, which is not the best practice. Let’s take an example. You can take a bottle of Coke and pinch the middle of the plastic bottle with your hands. You will find that there is less Coke in the middle because they are under pressure and flow to both sides. The same is true for spring bending. The density of PVC electrical pipe is a fixed value. Even if you bend the pipe with spring, it looks no problem to the naked eye, but its strength has changed, just like the Coke bottle, the Coke becomes less already, so the strength of the wire pipe itself is reduced.

Therefore, this problem can be easily solved by using a bend or elbow with an angle of 45° or 90°, and you do not need to worry about the strength of the conduit pipe.

You can also refer to the Fittings Post we wrote earlier, or check our Fittings product page, you will have a clearer understanding of how they work.

That’s it, thanks for your reading. You can contact us and leave your message to let us know what your problem is, we will reply to you shortly.

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