Blog

Hooking up a computer monitor is not terribly complicated but there are a few different types of cables that can be used to get the job done. Before even purchasing a monitor, start by checking the computer itself. Look at the back to the machine to see what kind of video ports are on there. Ideally, you will want the same type of connection on the monitor and computer. If you find yourself with a mismatching monitor and computer, you can use an adapter or converter to change one type of connection to another.

When making your selection, there are five main types of connections built onto modern monitors: VGA, DVI, HDMI, DisplayPort, and USB.

VGA

VGA (also called HD15) is an older type of video-only connection. Many used or outdated monitors will have this type of connection while newer models probably will not. VGA is the old standard for monitors and has since been replaced with newer formats. Out of all the monitor connections still in use today, VGA is the only one that is purely analog. This means VGA has a maximum resolution of 640 x 480, a far cry from the 1080p quality available with digital connections. Generally, users only want to use VGA if any of the newer, digital options are not available.

DVI

Coax cables are capable of transmitting radio frequency (RF) signals and have served as the backbone of communications technology for decades. From radios to telephones to televisions to computers, coax cable has seen continued use even as the technology it supports continues to evolve. Stretching back over 100 years, the origins of coax cables begin towards the end of the 19th century.

Oliver Heaviside, the grandfather of modern coax cable

1880: The original coax cable was created by English inventor Oliver Heaviside. Heaviside studied telegraph lines and discovered wrapping the lines with insulation reduced signal loss and made cables more durable. With this discovery, he created and patented the world’s first coax cable.

1884: A second coax cable is patented in Germany by the electrical engineering company Siemens & Halske (later merged with the company Siemens).

1894: Nikola Tesla files the first American patent on electrical conductors, which later become a key component in the birth of the modern coax cable.

1916: Lloyd E

Coax cables are fairly simple to assemble, but there are a few different ways to go about doing so. Having a good coax signal is heavily dependant on installing a connector correctly. If you are unsure about how to install a coax connector, see our installation guide here.

Whether crimp, solder, compression, and twist-on is the best option will depend on the exact setting the cable will be used in. Consider questions such as:

• Is the cable low- or high-voltage?
• Will it be used for field-work or factory-work?
• How experienced are the individuals working with the cable?
• How long is the cable expected to last?
• What is the budget?
• Will the cable be in a hazardous environment (extreme temperatures, exposure to chemicals, vibrating machinery, etc.)?

The details below cover the different options with general, overall performance in mind. If other factors come into play, a type of connector not normally considered “the best” could be your best option.

Crimp

Crimp connectors are the most popular option and the go-to for most professionals. Crimping has two large advantages over the other options: it is easy and it is fast. With good tools and enough know-how, a crimp connector can be attached in less than 30 seconds.

Crimping works by taking the metal sleeve of the connector and squeezing it tightly onto the cable, securing the connector into place. It sounds simple, but these connections are gas-tight and can hold up to any reasonable pull test when secured properly. The only special tool needed to install a crimp connector is a

Null modem, also called crossover, is a term associated with serial (RS-232) cables. A standard serial cable, also called an AT cable, has the wires inside the cable running straight through. Take a DB9 cable as an example. Pin 1 on one end of the cable would be connected to Pin 1 on the other end. Then Pin 2 to 2, 3 to 3, and so on. Null modem cables are serial cables that use an alternative pinout for different functionality.

A standard DB9 AT cable pinout (non-null modem)

Originally, all serial cables were AT cables and could not connect two devices (such as two computers) directly. They required a modem or similar equipment as a go-between. Null modem cables changed that old standard, allowing devices to be linked up directly with no middleman equipment. This allows older computers and other machines with serial ports to transfer data between each other directly, similar to more modern ethernet crossover cables.

Null modem cables work by switching around wire pairs when going from one end of the cable to the other. Returning to the DB9 example, a null modem cable would have Pin 2 on one side connected to Pin 3 on the other side. Then Pin 4 would be connected to Pin 6 and Pin 7 to Pin 8. Pins 1 and 9 are unused while Pin 5 still connects to itself, acting as the ground wire.

This type of null modem cable

NEMA and IEC are the two most common standards for power cords used in North America. NEMA connectors are on the side of the power cord that plugs into an AC wall outlet. IEC connectors are the side that plugs into devices like computers or TVs. By and large, NEMA and IEC are compatible with each other. There are many similarities between NEMA and IEC standards, but they are not quite the same.

NEMA Connectors

NEMA is an acronym for the National Electrical Manufacturers Association. Established in 1926, NEMA is an American organization focused on creating, establishing, and promoting safety standards for electrical equipment. Power cords are one of many items that fall under their jurisdiction. Despite being an American organization, NEMA standards are also primarily used in Canada and Mexico as well as parts of Central and South America, nearby small island nations such as Cuba, and some larger countries across the sea like Japan.

NEMA connectors are labeled as two numbers separated by a dash. The first number indicates the voltage rating of the cable; “5” stands for 125 volts and “6” stands for 250 volts. The second number indicates the amperage of the plug. There will also be a letter after the numbers, either a “P” for plug or an “R” for receptacle. For example, a NEMA l5-30p connector will be a plug rated for 125 volts and 30 amps.

Cables are the backbone of most modern technology. From simple ethernet cables keeping office computers online to heavy-duty power cables running hospital equipment, cables are involved with every aspect of technology. Even wireless devices like cell phones and tablets can only work by connecting to other devices like modems and routers that use cables themselves.

With cables being so critical, it is important to think economically when making purchases. However, once prices get too low it should set off a red flag. If something seems too good to be true, it usually is. Where cables are concerned, that can mean counterfeit cables that do not meet industry standards. These cables are unsafe and can damage themselves, the equipment they are connected to, and people unfortunate enough to be handling them.

Identifying Counterfeit Cables

Simply put, a counterfeit cable is any cable that does not meet industry standards. This often means using subpar materials to make the cable. Many counterfeit cables also go the extra step to try to deceive customers with false certification marks.

There are a few common counterfeit cable scams to look out for. At the foremost is cables made using inferior materials. One of the most common is copper-clad aluminum (CCA). Most cables use pure copper lines, with the exception of some coax cables that use copper-clad steel. CCA is no longer considered an industry standard but it is not entirely obsolete. Sometimes it is passed off as a cheap solution for jobs it is not qualified for.

Another common scam is faking certification labels. Many cables are tested to standards set by federally acknowledged facilities

In North America and Japan, special power cords are required for use with any equipment in a hospital or medical setting. Some other countries such as Australia, New Zealand, and Denmark use similar recommendations, but they are not technically required by law. This article will focus on power cords required for medical equipment in North America, most notably the United States and Canada.

In Technical Terms

Under regulatory and safety committees in the US and Canada, hospital-grade power cord requirements are highlighted under the following sections:

• UL 60601-1 and CAN/CSA C22.2 no. 21 (medical equipment standards)
• UL 817 and CAN/CSA 22.2 no. 21 (power supply cord standards)
• UL 498 and CAN/CSA 22.2 no. 42 (attachment plug and receptacle standards)

Additionally, they must conform to NEMA WD-6 and UL 817 by meeting the following requirements:

1. The blade plugs must be made of solid brass, not folded brass.
2. The blade plugs are nickel-plated.
3. The plug includes a strain relief or similar device to reduce stress on internal components.
4. The plug is marked with a “green dot” to signify it is hospital-grade.

These standards can apply to any cord that uses a NEMA 5-15, 5-20, 6-15, or 6-20 plug.

Ensuring an organized workspace and knowing the functions provided by a specific colored cable are critically important in any electrical setting. Putting the effort into planning out cable management ahead of time is always a good idea. A neat, organized structure makes it much easier to find the cable you are looking for whenever something needs to be unplugged or when trying to simplify knowing which cables perform what operations. Color coding your power cords can ease a complex situation and help you keep your peace of mind when trying to figure out a problem.

Color Coding Methodology

Keeping cords untangled is one thing, but color coding can ensure you always know which cables go where. Using different colors can be as simple as telling the new guy, “Do not unplug the grey one, that powers your computer.” A simple color coding system can ensure everyone knows which cable goes where with a simple glance. An ideal system will be simple, intuitive, and easy to manage.  

It is important to consider the limitations of a color coding system before jumping in too deep. For instance, are the colors being used in familiar ways (for example, a red cord being something you should not touch or could be dangerous)? Is there a chart of the color code somewhere in case people forget it? An organized set-up is good, but an organized set-up with foolproof back-up plans is better.

Along with general usage, color coding could be used to tell you something about the cables themselves. You could establish that 125-volt cables are green while 250-volt cords are red. Or each color could be a different wire gauge (AWG) so people know when to grab thicker cables for higher voltage connections.

For spaces with many connections, the colors could even be generalized like

In the age of the Internet, it is easier than ever before to be a thrifty shopper and find a bargain. When shopping around for any product, after a while you start to get a sense of what kind of price that particular item usually goes for. But as you dig around the Internet a bit more, you may stumble across an even better price. One that blows those other prices away. Something that seems too good to be true. And as the old saying goes: if something seems too good to be true, it probably is.

A power cord may seem simple at a glance, but there is a lot that goes into making one. A proper power cable is made of various materials in a specific fashion according to industry and government standards. However, there are many websites online that sell cables cheaply because their products do not meet those regulations. Sub-par cables are likely to burn out (literally as well as figuratively) quickly and can damage any connected equipment. A worst-case scenario could result in an electrical fire, injuries, or even death.

Identifying Cheap Cables

If you are accustomed to handling power cables, a cheap cord can often be identified by touch. You may notice that the cord or metal prongs on the end bend too easily, feels brittle, or seems to weigh less due to the cable containing insufficient materials.

If you do not know power cords well enough to test them by touch, then test them by sight. The easiest thing to look for is a product certification mark. There are different types of product certifications, depending on where the cable is being sold. Different countries have different regulatory committees, but they all tend to follow similar safety standards. On cheap cables,

Power cords, simply put, can be dangerous. Now when you think of the word “dangerous”, a power cord is probably not the first image that jumps into your head. And granted, a regular power cord is not as dangerous as something like a high voltage line at a substation. But while you may not need to be a licensed electrician to plug something into a wall outlet, it is important to remember that accidents do happen.

According to the U.S. Consumer Product Safety Commission (CPSC), roughly 4,000 people treated in emergency rooms are injured each year by power cords. Half of these injuries alone include fractures, contusions, lacerations, and sprains from people tripping over power cords. It is also estimated that roughly 3,300 home fires start each year due to power cords, with an estimated 270 people injured and 50 killed from the fires. Be safe, not a statistic.

Tripping Hazards

The number one cause of injury for power cords is tripping. A power cord should never be stretched across a room where people walk, even if it has enough slack to sit flat on the floor. Try to keep cords behind furniture or other fixtures to keep them out of the way. If a cord absolutely must go through an area with foot traffic, cover it with something like a speed bump to remove the danger of tripping.

On a similar note to tripping, make sure to keep cords out of the way if they are stretching upwards. You do not want a loose cord that a swinging elbow could accidentally catch, sending your electronics crashing to the ground. Making sure a cord is not within grabbing range of any curious children is also a good policy.