WesBell Electronics
Wire and Cable Blog



Posts tagged: underground cable

Shielded and Unshielded Tray Cable Information

Tray cable has a different meaning to a lot of people and each person seems to think that phrase describes exactly what they need, but more information is actually needed. There are many applications that require different types of tray cable and each will have their own specifications that are needed to extend the cable life as long as possible.

The main difference is shielded or unshielded because paying for a shield when you don’t need one is a waste of money. However, not getting a shield when you need one will cause many problems. Imagine a force field, or ring of vibration, that hovers outside of a cable due to the electrical current running through it. That’s called EMI which is “electromagnetic interference” that could interfere with other cables EMI or other equipment.

The shield over the copper conductors of a tray cable minimizes the EMI that can get outside the cable and also blocks other cables EMI from interferring with it. An unshielded tray cable can be used when it can’t interfere with any other cables or equipment.

For applications with very high EMI there is also a multipair tray cable that has sets of two twisted wires and a optional individual shield over each pair in the cable. The twist limits the EMI and the added shield over each pair lowers the EMI quite a bit more than a standard aluminum overall shield.

Voltage is the next difference to discuss because there are 300 and 600 volt tray cables available. The 300 volt PLTC (Power Limited Tray Cable) is commonly used indoors, outdoors and in conduit. The 600 volt tray cable has a larger outer diameter and it’s used outdoors, in conduit and directly underground.

Please call if you’re looking for any type of tray cable or if you have any questions or comments about our website. We work hard on the website to not only offer products for sale, but to inform buyers and users of why they’re buying a particular product we have. By getting into conversation about the application we have the ability to help them save money because they may not have needed everything they thought they did.

WesBell Electronics Inc
(800) 334-8400

Copper Electrical Cable Differences

Copper electrical cable is very expensive, but the real differences in price actually comes down to the insulation type more than the copper. Copper is the conductor of electricity in all copper electrical cables and the price of copper changes everyday. However, Romex 6/3® has the same amount of copper as UFB 6/3, so why is the price different?

A 6 awg wire is a 6 awg wire whether it’s in a Romex NMB® jacket or a tough underground PVC jacket. That means each 6 awg wire would be the same price if they were both stripped of all insulation. A UFB underground insulation was manufactured to be used without conduit. So the jacket needed extra protection in order to last as long as an electrical cable in conduit.

In order of the amount of protection Romex® comes first, MC cable second and UFB cable third for electrical cables. Even though each of these cables have different levels of protection they all still have THHN THWN as the wire conductor insulation, so what changes the fact that some have more restrictions?

Romex® cable has a bare copper uninsulated ground wire, but lacks a strong enough jacket to protect it outdoors or in conduit. Moisture, gas, solvents and other fluids can puncture the jacket and hit the bare ground wire leaving it only available for wiring indoors.

MC cable is manufactured with all THHN wires and a THHN insulated green ground wire. That allows MC electrical cables to be used outdoors and in conduit because it resists all water, moisture oils and gases without an uninsulated ground wire in the way.

UFB cable is manufactured as an underground electrical cable which is also known as direct burial in the wire and cable industry. It still has an uninsulateed ground wire but the PVC jacket is engineered tough enough to protect all of the wires even when used directly underground.

In order to find the cheapest cable possible you’ll want to first speak to an electrician to let you know the awg size of the cable you need. This will prevent you from getting a size too big and paying more money than you need to. The second thing you want to do is make sure you’re not getting too much insulation that you may not need. Getting UFB cable when you’re using conduit anyways is a waste of money. You should get MC cable which is cheaper and manufactured for use in conduit.

We offer exact cut lengths on all of our electrical cables and THHN wire because in the contractors, engineers and installers like to have the exact length they need to avoid waste of small lengths at the end of each spool. We also offer free shipping on orders over $250 so that you don’t have to negociate deals with trucking companies to get spool of wire or cable.

Please call us if you need any type of wire, cable or heat shrink tubing as we’ve been a stocking distributor for over 25 years.

WesBell Electronics Inc
(800) 334-8400

Romex and UFB Electrical Wire Pricing Lowered!

Since copper is a daily fluctuating commodity we must keep up to date on our copper wire and cable pricing. Over the last month alone copper rose above $4.20 per pound, came back down to $3.20 per pound and has settled in the last few days around $3.60 per pound.

When buying and selling copper electrical wire such as Romex® and UFB underground cable we have to watch the pricing very carefully because the amount of copper in each conductor can drastically change the price. When copper goes down we have to lower our pricing in order to compete with other wire and cable distributors and when pricing goes up we have to increase our pricing so that we don’t lose money on orders.

With that being said, over the last few days WesBell has lowered all pricing on copper wire and cable in order to show our customers we’re honest and not trying to make “extra money” while copper is decreasing. We’ve heard many stories from our customers that their electrical wire vendor increased pricing when copper was high but didn’t decrease pricing when copper lowered.

We like to keep our customers informed of when copper is increasing and decreasing by showing them on our website. We keep the last 3 years worth of copper pricing online so that when you buy something that you haven’t bought in over a year you can see exactly why there was a price increase or decrease.

The last thing we want to hear is that our pricing is 10% higher than our competitor because we work hard to please our customers in every way and a higher price can give a potential customer a bad impression of our entire company. We stay on top of copper, stay current on pricing, offer free shipping on orders over $250, ship from the tax free state of NH, offer exact cut lengths and stand by our on time delivery as one of our top 3 ISO9001 quality objectives.

As an ISO9001 company we analyze, and document, everything that goes wrong, discuss it, and implement a new procedure to be sure that it can’t happen again. Being an ISO certified company is so much more than “extra paperwork”. It forces companies to do the right thing, take the right steps forward and to, not only look for new customers, but to take a step back and be sure you’re pleasing your current customers even more.

People talk about money multiple times a day so we know how important our wire and cable pricing is to our customers. We look at other websites pricing before uploading ours so that we know we’re competitive. If we’re not please let us know!

Please call if you have and questions or comments about our website.

WesBell Electronics, Inc
(800) 334-8400

Electrical Wire Questions and Answers

We get a lot of phone calls and emails with questions about many different types of electrical wire and cable. Since some of them are repeated we’re going to put them on our website so that people can find the answer before they need to make a phone call.

What type of electrical cable do I use to run electricity to my barn or garage?

If it’s above ground or in conduit you can use SER (Service Entrance Cable). Talk to an electrician first to check the gauge of the cable you’ll need. The electrician will do a calculation based on the length of the cable, the amount of amps you need and the voltage.

If you want to run the cable directly underground then you need to use UFB cable or Tray cable. UFB cable is an underground feeder that has added protection to be used underground. If you need something bigger than 6 awg then you’ll need to use tray cable which can also be used directly underground. Tray cable gets as big as 750 mcm with 4 conductors plus a ground wire.

Can I use Romex wire if it’s only going to be outdoors for 10 feet?

No matter how long I work for a wire and cable company I know this question will continue to come up. Romex can NOT be used outdoors because the jacket insulation isn’t manufactured with enough protection to resist any moisture, gas, oil or solvents. Anything that penetrates the jacket could hit the bare copper ground wire and short the connection.

Can I use THHN as dog fence wire?

Only if you keep the wire above ground. Usually dog fence wire is buried in the ground so you’ll need a wire that has enough protection to be used directly underground. THHN wire is used indoors, outdoors and in conduit only. The manufacturer states that THHN can not be used underground so that’s the message we pass along.

What type of wire do I use if I need high temperature?

Standard PVC hook up wire is rated for 105°C with a few different voltage ratings available. If you need higher temperature then you should use PTFE wire which is rated up to 200C. It’s silver plated copper with a PTFE insulation and it’s getting more expensive by the minute. Copper is rising, silver is rising and PTFE compound is also rising to give PTFE wire 3 possible inceases each day.

Please email or call us with any questions you might have about electrical wire and cable.

WesBell Electronics Inc
(800) 334-8400

Indoor Outdoor and Underground Copper Electrical Wire

Electrical wire comes with all different types of insulation, but they all have the common denominator of copper or aluminum stranding. The insulation changes the expense of the wire or cable based on the environment you need to place it in.

Indoor Wire and Cable

THHN wire is the most common type of single conductor electrical wire. It’s manufactured with a dual rating of THHN and THWN so that it’s all water resistant. It can be used indoors and in conduit only.

Using your copper wire and cable indoors requires the least amount of protection on the insulation because there isn’t much that can hurt it. There isn’t any moisture, oil or solvents effecting the life of the insulation so it can be made for less money. Romex cable is the most common type of indoor electrical wire which uses THHN wire conductors.

Outdoor Wire and Cable

THHN is still the single conductor wire used outdoors and in conduit because the THWN rating can resist water, oil, gases and solvents. However, running 3-4 single wires can be difficult for the installer because they’ll have to run each one individually or tie all 3 together and try to run them as one.

Romex will not work outdoors OR in conduit so you’ll have to upgrade in quality and price to an MC Cable. It’s manufactured with THHN wires and a Metal Clad jacket for easy installation in conduit. The ground wire in MC cable is also a THHN wire rather than a bare copper ground wire so the cable remains moisture and solvent resistant.

Underground Electrical Wire

THHN cannot be buried directly in the ground so you’ll have to upgrade on a single conductor to USE-2 wire. It’s used mostly on solar installations and has a rubber insulation.

If your installation is directly in the Earth instead of in conduit then you’ll have to upgrade to a UFB cable which is an underground feeder cable. It’s color coded and flat instead of round with a bare copper ground wire. The insulation covers each conductor individually to keep it water and moisture tight directly underground.

Tray cable is also an underground cable for larger sizes since UFB cable only goes as large as 6 awg 3 conductor. Tray cable goes as big as 500 mcm 4 conductor with ground. It has all black numbered THHN conductors and an overall PVC jacket. We sell it per foot on our website so that you can get the exact length you need and avoid any waste.

Those are the basics of indoor and outdoor electrical wire. There are also basics on electronic wire and cable based on heat and voltage ranges for different applications.

WesBell Electronics Inc
(800) 334-8400

Tray Cable is the Newest Electrical Wire Addition

The newest product addition to WesBell has been tray cable because of the amount of uses this type of electrical wire has. It’s universal in a sense because it can be used just about anywhere without an oversized jacket.

THHN / PVC Tray Cable is the standard type with THHN wires and a bare copper ground wire. Each wire is black with a number code of 1 through 4. The tough outer PVC jacket has the approvals for direct burial in the earth.

Another type of underground cable available in this field is UFB Cable. The difference with UFB wire is that it’s color coded and flat rather than round. It’s the common step up in smaller applications up to 6 awg from Romex and MC cable. Romex can be used indoors and MC cable can be used outdoors but not directly underground.

However, if you need a bigger gauge underground cable then tray cable sounds like a good fit for your application. It’s 600 volts type TC-ER tray cable and comes in copper conductors only.

There are many types of electrical wire types even though most of them come with copper conductors. Each insulation type is a step up from the next to offer a variety of pricing. Obviously and indoor only cable will be cheaper than one that can be buried directly in the ground because of the approvals and tests it needs to go through. So be sure to tell your sales person exactly what you’re using your electrical cable for in order to pay the lowest price possible.