Serial Cable Maximum Length

1. Serial Cable Maximum Length Comparison
2. Serial Cable Maximum Length Weight Chart
3. Maximum Length Of Serial Cable

Well sending serial will be much better over longer lengths than mass storage data transfer but the max length for USB 1.1 is 3m: Quote USB 1.1 maximum cable length is 3 metres (9.8 ft) and USB 2.0 maximum cable length is 5 metres (16 ft).31.

RS232 specifications, introduction

1. I've been cross referencing various training books and the serial cable seems to be 25ft or 50ft depending on which one you read The parallel cable seems to be either 6ft, or 10ft, or 16ft depending on which book you read. I'd hate to get the question wrong in the exam due to incorrect information in the training guides.
2. At lower peripheral speeds of up to 9600 baud,serial interfaces can usually operate over cables up to 50 feet long. Use of special high quality cable may in some cases allow this limit to be extended to as much as 150 feet. Parallel Cables Length Limits.

Communication as defined in the RS232 standard is an asynchronous serial communication method. The word serial means, that the information is sent one bit at a time. Asynchronous tells us that the information is not sent in predefined time slots. Data transfer can start at any given time and it is the task of the receiver to detect when a message starts and ends. Asynchronous communication has some advantages and disadvantages which are both discussed in the next paragraph.

RS232 bit streams

The RS232 standard describes a communication method where information is sent bit by bit on a physical channel. The information must be broken up in data words. The length of a data word is variable. On PC's a length between 5 and 8 bits can be selected. This length is the net information length of each word. For proper transfer additional bits are added for synchronization and error checking purposes. It is important, that the transmitter and receiver use the same number of bits. Otherwise, the data word may be misinterpreted, or not recognized at all.

With synchronous communication, a clock or trigger signal must be present which indicates the beginning of each transfer. The absence of a clock signal makes an asynchronous communication channel cheaper to operate. Less lines are necessary in the cable. A disadvantage is, that the receiver can start at the wrong moment receiving the information. Re-synchronization is then needed which costs time. All data received in the re-synchronization period is lost. Another disadvantage is that extra bits are needed in the data stream to indicate the start and end of useful information. These extra bits take up bandwidth.

Data bits are sent with a predefined frequency, the baud rate. Both the transmitter and receiver must be programmed to use the same bit frequency. After the first bit is received, the receiver calculates at which moments the other data bits will be received. It will check the line voltage levels at those moments.

With RS232, the line voltage level can have two states. The on state is also known as mark, the off state as space. No other line states are possible. When the line is idle, it is kept in the mark state.

Start bit

RS232 defines an asynchronous type of communication. This means, that sending of a data word can start on each moment. If starting at each moment is possible, this can pose some problems for the receiver to know which is the first bit to receive. To overcome this problem, each data word is started with an attention bit. This attention bit, also known as the start bit, is always identified by the space line level. Because the line is in mark state when idle, the start bit is easily recognized by the receiver.

Data bits

Directly following the start bit, the data bits are sent. A bit value 1 causes the line to go in mark state, the bit value 0 is represented by a space. The least significant bit is always the first bit sent.

Parity bit

For error detecting purposes, it is possible to add an extra bit to the data word automatically. The transmitter calculates the value of the bit depending on the information sent. The receiver performs the same calculation and checks if the actual parity bit value corresponds to the calculated value. This is further discussed in another paragraph.

Stop bits

Suppose that the receiver has missed the start bit because of noise on the transmission line. It started on the first following data bit with a space value. This causes garbled date to reach the receiver. A mechanism must be present to re-synchronize the communication. To do this, framing is introduced. Framing means, that all the data bits and parity bit are contained in a frame of start and stop bits. The period of time lying between the start and stop bits is a constant defined by the baud rate and number of data and parity bits. The start bit has always space value, the stop bit always mark value. If the receiver detects a value other than mark when the stop bit should be present on the line, it knows that there is a synchronization failure. This causes a framing error condition in the receiving UART. The device then tries to re-synchronize on new incoming bits.

For re-synchronizing, the receiver scans the incoming data for valid start and stop bit pairs. This works, as long as there is enough variation in the bit patterns of the data words. If data value zero is sent repeatedly, re-synchronization is not possible for example.

The stop bit identifying the end of a data frame can have different lengths. Actually, it is not a real bit but a minimum period of time the line must be idle (mark state) at the end of each word. On PC's this period can have three lengths: the time equal to 1, 1.5 or 2 bits. 1.5 bits is only used with data words of 5 bits length and 2 only for longer words. A stop bit length of 1 bit is possible for all data word sizes.

RS232 physical properties

The RS232 standard describes a communication method capable of communicating in different environments. This has had its impact on the maximum allowable voltages etc. on the pins. In the original definition, the technical possibilities of that time were taken into account. The maximum baud rate defined for example is 20 kbps. With current devices like the 16550A UART, maximum speeds of 1.5 Mbps are allowed.

Voltages

The signal level of the RS232 pins can have two states. A high bit, or mark state is identified by a negative voltage and a low bit or space state uses a positive value. This might be a bit confusing, because in normal circumstances, high logical values are defined by high voltages also. The voltage limits are shown below.

More information about the voltage levels of RS232 and other serial interfaces can be found in the interface comparison table.

The maximum voltage swing the computer can generate on its port can have influence on the maximum cable length and communication speed that is allowed. Also, if the voltage difference is small, data distortion will occur sooner. For example, my Toshiba laptop mark's voltage is -9.3 V, compared to -11.5 V on my desktop computer. The laptop has difficulties to communicate with Mitsubishi PLCs in industrial environments with high noise levels where the desktop computer has no data errors at all using the same cable. Thus, even far beyond the minimum voltage levels, 2 volts extra can make a huge difference in communication quality.

Despite the high voltages present, it is not possible to destroy the serial port by short-circuiting. Only applying external voltages with high currents may eventually burn out the driver chips. Still then, the UART won't be damaged in most cases.

Maximum cable lengths

Cable length is one of the most discussed items in RS232 world. The standard has a clear answer, the maximum cable length is 50 feet, or the cable length equal to a capacitance of 2500 pF. The latter rule is often forgotten. This means that using a cable with low capacitance allows you to span longer distances without going beyond the limitations of the standard. If for example UTP CAT-5 cable is used with a typical capacitance of 17 pF/ft, the maximum allowed cable length is 147 feet.

The cable length mentioned in the standard allows maximum communication speed to occur. If speed is reduced by a factor 2 or 4, the maximum length increases dramatically. Texas Instruments has done some practical experiments years ago at different baud rates to test the maximum allowed cable lengths. Keep in mind, that the RS232 standard was originally developed for 20 kbps. By halving the maximum communication speed, the allowed cable length increases a factor ten!

Error detection

One way of detecting errors is already discussed. It is the frame detection mechanism which is used to test if the incoming bits were properly surrounded by a start and stop bit pair. For further error checking, a parity bit can be used. The use of this bit is however not mandatory. If the existence of wrong bits is rare (when communicating with an internal modem for example) or if a higher level protocol is used for error detection and correction (Z-modem, RAS, etc) communication speed can be increased by not using the parity feature present on the UART.

Parity is a simple way to encode a data word to have a mechanism to detect an error in the information. The method used with serial communications adds one bit to each data word. The value of this bit depends on the value of the data word. It is necessary that both the transmitter and receiver use the same algorithm to calculate the value of the parity bit. Otherwise, the receiver may detect errors which are not present.

Even parity

Basically, the parity bit can be calculated in two ways. When even parity is used, the number of information bits sent will always contain an even number of logical 1's. If the number of high data bits is odd, a high value parity bit is added, otherwise a low bit will be used.

Odd parity

The odd parity system is quite similar to the even parity system, but in this situation, the number of high bits will always be odd.

Disadvantages of the parity system

The parity system using one bit for each data word is not capable of finding all errors. Only errors which cause an odd number of bits to flip will be detected. The second problem is, that there is no way to know which bit is false. If necessary, a higher level protocol is necessary to inform the sender that this information must be resent. Therefore, on noisy lines, often other detection systems are used to assure that the sent information is received correctly. These systems mostly do not operate on single data words, but on groups of words. Known coding systems are:

• Hamming coding

But now, we spend the bulk of our waking lives looking at electronic displays, and the need to get AV signals from source to display over longer distances has become more important than ever; both in our homes and out. But not all cables have kept up the pace.

Below, we detail the current limitations of the most common digital and analogue formats – you can read about the only format that affects you, or read the whole article to wield the power of a home theatre titan!

HDMI is so popular that its old length limits have been blasted out of the water with a variety of innovations which all come in at different price points. We'll look at each of the options we stock here at Cable Chick:

• Basic HDMI: This covers cables that meet the HDMI certification standard and don't have anything extra built in. These cables range from our cheapest to our most high-end Amped Onyx series. They contain the required 19 cores of high-grade copper, plus varying degrees of shielding in line with their price point. More expensive cables can accomodate higher resolutions over longer lengths and also work better with splitters and switches. Basic and budget level HDMIs are best for short lengths and direct connections between powered sources and displays. Alone, these cables can take HDMI 20 metres.
  See our longest regular HDMI cable here!

• Boosted HDMI: HDMI cables which have a booster integrated into their structure use the 5v power rail of the HDMI signal to carry the data further without loss of fidelity. This boost is commonly used to make longer cable runs, but it can also be used to make a short cable thinner and much more flexible. HDMI cables with integrated booster chipsets are more expensive than their basic counterparts, and so far only cater to 1080p content due to the loss of bandwidth over the extended length, but they can reach 40 metres.
  See our longest Boosted HDMI cable here!

• HDMI over CAT: Using Cat5 or Cat6 cables to extend an AV source is not a new concept, and HDMI can make use of this technology for stable extended runs – sometimes even using existing network cabling. Due to bandwidth limitations, most CAT extenders only support 1080p, but some can handle 3D, too. Configuration is more complex than regular cables, and interference can be a big problem in some environments, but with a good HDMI over Cat5/6 Extender, you can run 50 metres.
  See our Premium HDMI Extender Kit here!
  Special Note: Some devices can also leverage Ethernet-based LANs for video and audio extension from a PC. See our PC to HDMI & VGA over LAN converter here!

• HDMI over Fibre Optics: Fibre Optic kits for HDMI carry the highest price premium of all, but they have the capacity to outstrip copper based cables for distance by a large margin. The added benefit to this cable type is flexibility. The Optical core is much smaller than Boosted HDMI, but can go the same distances. As of this writing, Cable Chick's longest HDMI over Optical Fibre Cable is 45 metres, but some companies have kits which run much longer (and cost far more!)
  See our HDMI over Fibre Kit here!

• HDMI over Wireless: Wireless technologies vary between models, but one thing they have in common is they don't generally go as far as cables do. Line of sight is 10 to 15 metres, and through walls can be as low as 5 to 8 metres. Unless you can't run a cable at all, a lead will beat Wireless every time. Wireless is also limited by bandwith to 1080p, and only the best units can handle 3D.
  See our Wireless HDMI Kit here!

Want to know more about separately available HDMI booster accessories? We cover them in our article on Couplers and Adapters (*coming soon!).

DVI has three main flavours, but the two we deal with most of all are DVI-D Single Link and DVI-D Dual Link. The Single-Link variation is basically the same as the video portion of a HDMI signal, and for resolutions up to 1080p, it can easily run 15 metres. By using HDMI adapters, you can use boosters to go even further.
See our longest DVI-D cable here!

However, when you push past Full HD and into the world of 27' and 30' computer monitors, Dual-Link bandwidth is required to get the signal across. At resolutions up to 2560x1600, your cable run length is limited to 5 metres.

At present, there are no reliable booster technologies which can be leveraged for DVI-D Dual Link at higher-than-HD resolutions. If you try to use a cable longer than 5 metres, your display will automatically drop down to 1080p simply because it has run out of bandwidth over the longer cable.
Fire emblem fates revelation citra. See our 5 metre DVI-D Dual Link cable here!

Because DisplayPort was so ahead of its time in terms of bandwidth and resolution capability when it was launched, strict limits were set on what cable lengths could be certified. This decision limited confusion in the market place, but set the maximum limit for a certified DisplayPort cable at 5 metres.
See our longest DisplayPort cable here!

Using couplers to join two certified DisplayPort cables together for a run longer than 5 metres will result in loss of signal. There is currently no workaround for this length limit.

Like Dual-Link DVI, VGA accommodates many resolutions, each of which requires a different amount of bandwidth. As cables get longer, the available bandwidth decreases and with it the highest potential display resolution is lowered. A short VGA cable can manage 1920x1080 without trouble. A long VGA cable may top out at 1024x768, and our longest offering may struggle to reach 800x600.

• Basic VGA: For a single cable, it's always important to consider your requirements and the installation environment before opting to use a VGA cable over 5 or 10 metres. But if resolution isn't an issue, we stock all the way up to 40 metres.
  See our longest VGA cable here!

• VGA over CAT: To overcome these limitations, we carry a VGA over CAT5/6 Extender kit. With this sender/receiver pair, bandwidth is boosted considerably – allowing for 1024x768 to reach 75 metres, and 640x480 to reach 300 metres.
  See our VGA Extender kit here!

The new SuperSpeed USB standard has its own set of rules for maximum length, so we'll look at each standard separately. Because of its age, USB 2.0 has more workarounds on the market than USB 3.0, but come with some important caveats.

• USB 3.0: Extra pins. Higher speeds. More bandwidth. The ability of USB3.0 to achieve these accolades relies on the cable most of all, yet the USB 3.0 standards don't specify a maximum cable length. However, our testing has shown that there is a definite failure point for USB 3.0 (especially when using portable hard drives). For devices requiring power over USB, 2 metres is foolproof. For self-powered devices using an internal battery or direct wall socket connection, we carry a 3 metre cable.
  See our longest USB 3.0 A/B cable here!

• Basic USB 2.0: It's everywhere. From flash drives to digital cameras and from portable hard drives to printers, you can't escape USB 2.0! Because of its ubiquitous nature, USB has to be a Jack of All Trades in terms of power delivery and bandwidth. As such, regular USB 2.0 cables have a limit of 5 metres to meet the certification standard. You can go longer with USB extensions, and data may still get through, provided that the device (hard-drive, printer, etc) is independently powered.
  See our longest USB 2.0 A/A cable here!

• Boosted USB 2.0: We stock two lengths of USB 2.0 cable which feature integrated repeater/booster chipsets, both of which can be daisy-chained repeatedly. The downside to this method is that the 5v power rail is used for boosting, and is therefore not available for powering a connected device – great for printers plugged into mains power, but not so good for portable hard drives. Our boosted USB 2.0 cables come in 5 metres and 12 metres, and can be chained together for runs up to 36 metres!
  See our longest Boosted USB 2.0 cable here!

• USB 2.0 over CAT: Based on a similar principle to HDMI over CAT, USB 2.0 can also be greatly extended using a Cat5 or Cat6 cable. You'll experience the same limitation on USB-powered devices as the booster chips above, but a good link can get your USB 2.0 signal to go 80 metres.
  See our USB 2.0 Extender kit here!

• USB Hub Daisy-Chaining: It may be possible to string together multiple powered hubs to extend the range of USB 2.0 and/or USB 3.0. So long as each hub gets it power from an external (non USB) source, it is theoretically possible to exceed the above length limits. We haven't tested this ourselves, so we don't know what the limit is..
  See our Powered USB Hub here!

Toslink (optical SPDIF) relies on a pulse of light to operate, and as such doesn't suffer from signal loss due to electromagnetic or RF interference. It is also unaffected by electrical resistance, but there are two important aspects which play a role in length limitations: The clarity of the optical core inside the cable, and the strength of the light source inside the hardware.

Toslink cables intended for consumer-level use contain plastic optical fibres. This makes them robust, flexible and great for lengths up to 15 metres - provided that the source device has a strong enough output.
See our longest TOSLINK cable here!

It is possible to track down Toslink cables that have glass fibre cores. These cables can potentially go much, much farther than plastic, but their fragility and extreme cost make them unworkable (and unnecessary) for most homes. If you are finding that a 15m TOSLINK cable is failing, it's more likley the source device is too weak rather than the cable being faulty.

Analogue formats bear a unique burden in that there is no parity check to ensure that the display device is receiving uncorrupted data. Coupled with the simpler technology which powers these standards, they suffer greatly from signal loss over long lengths.

Put simply, the farther you go with analogue, the worse it looks or sounds. Sure, you can run a 50 metre component video cable (if you could find one) but the quality of the image at the far end would be horrible. It's here, with analogue, that cable quality matters most.

• CVBS & YPbPr Video: Our longest length in these formats is 20 metres, but your mileage will vary greatly between our cheapest and most expensive options. If you want a crystal-clear signal over the longest length, only Amped Onyx can provide the best signal, and after that it comes down to your environment and source quality.
  See our best and longest RCA Video cable here!

Communication as defined in the RS232 standard is an asynchronous serial communication method. The word serial means, that the information is sent one bit at a time. Asynchronous tells us that the information is not sent in predefined time slots. Data transfer can start at any given time and it is the task of the receiver to detect when a message starts and ends. Asynchronous communication has some advantages and disadvantages which are both discussed in the next paragraph.

RS232 bit streams

The RS232 standard describes a communication method where information is sent bit by bit on a physical channel. The information must be broken up in data words. The length of a data word is variable. On PC's a length between 5 and 8 bits can be selected. This length is the net information length of each word. For proper transfer additional bits are added for synchronization and error checking purposes. It is important, that the transmitter and receiver use the same number of bits. Otherwise, the data word may be misinterpreted, or not recognized at all.

With synchronous communication, a clock or trigger signal must be present which indicates the beginning of each transfer. The absence of a clock signal makes an asynchronous communication channel cheaper to operate. Less lines are necessary in the cable. A disadvantage is, that the receiver can start at the wrong moment receiving the information. Re-synchronization is then needed which costs time. All data received in the re-synchronization period is lost. Another disadvantage is that extra bits are needed in the data stream to indicate the start and end of useful information. These extra bits take up bandwidth.

Data bits are sent with a predefined frequency, the baud rate. Both the transmitter and receiver must be programmed to use the same bit frequency. After the first bit is received, the receiver calculates at which moments the other data bits will be received. It will check the line voltage levels at those moments.

With RS232, the line voltage level can have two states. The on state is also known as mark, the off state as space. No other line states are possible. When the line is idle, it is kept in the mark state.

Start bit

RS232 defines an asynchronous type of communication. This means, that sending of a data word can start on each moment. If starting at each moment is possible, this can pose some problems for the receiver to know which is the first bit to receive. To overcome this problem, each data word is started with an attention bit. This attention bit, also known as the start bit, is always identified by the space line level. Because the line is in mark state when idle, the start bit is easily recognized by the receiver.

Data bits

Directly following the start bit, the data bits are sent. A bit value 1 causes the line to go in mark state, the bit value 0 is represented by a space. The least significant bit is always the first bit sent.

Parity bit

For error detecting purposes, it is possible to add an extra bit to the data word automatically. The transmitter calculates the value of the bit depending on the information sent. The receiver performs the same calculation and checks if the actual parity bit value corresponds to the calculated value. This is further discussed in another paragraph.

Stop bits

Suppose that the receiver has missed the start bit because of noise on the transmission line. It started on the first following data bit with a space value. This causes garbled date to reach the receiver. A mechanism must be present to re-synchronize the communication. To do this, framing is introduced. Framing means, that all the data bits and parity bit are contained in a frame of start and stop bits. The period of time lying between the start and stop bits is a constant defined by the baud rate and number of data and parity bits. The start bit has always space value, the stop bit always mark value. If the receiver detects a value other than mark when the stop bit should be present on the line, it knows that there is a synchronization failure. This causes a framing error condition in the receiving UART. The device then tries to re-synchronize on new incoming bits.

For re-synchronizing, the receiver scans the incoming data for valid start and stop bit pairs. This works, as long as there is enough variation in the bit patterns of the data words. If data value zero is sent repeatedly, re-synchronization is not possible for example.

The stop bit identifying the end of a data frame can have different lengths. Actually, it is not a real bit but a minimum period of time the line must be idle (mark state) at the end of each word. On PC's this period can have three lengths: the time equal to 1, 1.5 or 2 bits. 1.5 bits is only used with data words of 5 bits length and 2 only for longer words. A stop bit length of 1 bit is possible for all data word sizes.

RS232 physical properties

The RS232 standard describes a communication method capable of communicating in different environments. This has had its impact on the maximum allowable voltages etc. on the pins. In the original definition, the technical possibilities of that time were taken into account. The maximum baud rate defined for example is 20 kbps. With current devices like the 16550A UART, maximum speeds of 1.5 Mbps are allowed.

Voltages

The signal level of the RS232 pins can have two states. A high bit, or mark state is identified by a negative voltage and a low bit or space state uses a positive value. This might be a bit confusing, because in normal circumstances, high logical values are defined by high voltages also. The voltage limits are shown below.

More information about the voltage levels of RS232 and other serial interfaces can be found in the interface comparison table.

The maximum voltage swing the computer can generate on its port can have influence on the maximum cable length and communication speed that is allowed. Also, if the voltage difference is small, data distortion will occur sooner. For example, my Toshiba laptop mark's voltage is -9.3 V, compared to -11.5 V on my desktop computer. The laptop has difficulties to communicate with Mitsubishi PLCs in industrial environments with high noise levels where the desktop computer has no data errors at all using the same cable. Thus, even far beyond the minimum voltage levels, 2 volts extra can make a huge difference in communication quality.

Despite the high voltages present, it is not possible to destroy the serial port by short-circuiting. Only applying external voltages with high currents may eventually burn out the driver chips. Still then, the UART won't be damaged in most cases.

Maximum cable lengths

Cable length is one of the most discussed items in RS232 world. The standard has a clear answer, the maximum cable length is 50 feet, or the cable length equal to a capacitance of 2500 pF. The latter rule is often forgotten. This means that using a cable with low capacitance allows you to span longer distances without going beyond the limitations of the standard. If for example UTP CAT-5 cable is used with a typical capacitance of 17 pF/ft, the maximum allowed cable length is 147 feet.

The cable length mentioned in the standard allows maximum communication speed to occur. If speed is reduced by a factor 2 or 4, the maximum length increases dramatically. Texas Instruments has done some practical experiments years ago at different baud rates to test the maximum allowed cable lengths. Keep in mind, that the RS232 standard was originally developed for 20 kbps. By halving the maximum communication speed, the allowed cable length increases a factor ten!

Error detection

One way of detecting errors is already discussed. It is the frame detection mechanism which is used to test if the incoming bits were properly surrounded by a start and stop bit pair. For further error checking, a parity bit can be used. The use of this bit is however not mandatory. If the existence of wrong bits is rare (when communicating with an internal modem for example) or if a higher level protocol is used for error detection and correction (Z-modem, RAS, etc) communication speed can be increased by not using the parity feature present on the UART.

Parity is a simple way to encode a data word to have a mechanism to detect an error in the information. The method used with serial communications adds one bit to each data word. The value of this bit depends on the value of the data word. It is necessary that both the transmitter and receiver use the same algorithm to calculate the value of the parity bit. Otherwise, the receiver may detect errors which are not present.

Even parity

Basically, the parity bit can be calculated in two ways. When even parity is used, the number of information bits sent will always contain an even number of logical 1's. If the number of high data bits is odd, a high value parity bit is added, otherwise a low bit will be used.

Odd parity

The odd parity system is quite similar to the even parity system, but in this situation, the number of high bits will always be odd.

Disadvantages of the parity system

The parity system using one bit for each data word is not capable of finding all errors. Only errors which cause an odd number of bits to flip will be detected. The second problem is, that there is no way to know which bit is false. If necessary, a higher level protocol is necessary to inform the sender that this information must be resent. Therefore, on noisy lines, often other detection systems are used to assure that the sent information is received correctly. These systems mostly do not operate on single data words, but on groups of words. Known coding systems are:

• Hamming coding

But now, we spend the bulk of our waking lives looking at electronic displays, and the need to get AV signals from source to display over longer distances has become more important than ever; both in our homes and out. But not all cables have kept up the pace.

Below, we detail the current limitations of the most common digital and analogue formats – you can read about the only format that affects you, or read the whole article to wield the power of a home theatre titan!

HDMI is so popular that its old length limits have been blasted out of the water with a variety of innovations which all come in at different price points. We'll look at each of the options we stock here at Cable Chick:

• Basic HDMI: This covers cables that meet the HDMI certification standard and don't have anything extra built in. These cables range from our cheapest to our most high-end Amped Onyx series. They contain the required 19 cores of high-grade copper, plus varying degrees of shielding in line with their price point. More expensive cables can accomodate higher resolutions over longer lengths and also work better with splitters and switches. Basic and budget level HDMIs are best for short lengths and direct connections between powered sources and displays. Alone, these cables can take HDMI 20 metres.
  See our longest regular HDMI cable here!

• Boosted HDMI: HDMI cables which have a booster integrated into their structure use the 5v power rail of the HDMI signal to carry the data further without loss of fidelity. This boost is commonly used to make longer cable runs, but it can also be used to make a short cable thinner and much more flexible. HDMI cables with integrated booster chipsets are more expensive than their basic counterparts, and so far only cater to 1080p content due to the loss of bandwidth over the extended length, but they can reach 40 metres.
  See our longest Boosted HDMI cable here!

• HDMI over CAT: Using Cat5 or Cat6 cables to extend an AV source is not a new concept, and HDMI can make use of this technology for stable extended runs – sometimes even using existing network cabling. Due to bandwidth limitations, most CAT extenders only support 1080p, but some can handle 3D, too. Configuration is more complex than regular cables, and interference can be a big problem in some environments, but with a good HDMI over Cat5/6 Extender, you can run 50 metres.
  See our Premium HDMI Extender Kit here!
  Special Note: Some devices can also leverage Ethernet-based LANs for video and audio extension from a PC. See our PC to HDMI & VGA over LAN converter here!

• HDMI over Fibre Optics: Fibre Optic kits for HDMI carry the highest price premium of all, but they have the capacity to outstrip copper based cables for distance by a large margin. The added benefit to this cable type is flexibility. The Optical core is much smaller than Boosted HDMI, but can go the same distances. As of this writing, Cable Chick's longest HDMI over Optical Fibre Cable is 45 metres, but some companies have kits which run much longer (and cost far more!)
  See our HDMI over Fibre Kit here!

• HDMI over Wireless: Wireless technologies vary between models, but one thing they have in common is they don't generally go as far as cables do. Line of sight is 10 to 15 metres, and through walls can be as low as 5 to 8 metres. Unless you can't run a cable at all, a lead will beat Wireless every time. Wireless is also limited by bandwith to 1080p, and only the best units can handle 3D.
  See our Wireless HDMI Kit here!

Want to know more about separately available HDMI booster accessories? We cover them in our article on Couplers and Adapters (*coming soon!).

DVI has three main flavours, but the two we deal with most of all are DVI-D Single Link and DVI-D Dual Link. The Single-Link variation is basically the same as the video portion of a HDMI signal, and for resolutions up to 1080p, it can easily run 15 metres. By using HDMI adapters, you can use boosters to go even further.
See our longest DVI-D cable here!

However, when you push past Full HD and into the world of 27' and 30' computer monitors, Dual-Link bandwidth is required to get the signal across. At resolutions up to 2560x1600, your cable run length is limited to 5 metres.

At present, there are no reliable booster technologies which can be leveraged for DVI-D Dual Link at higher-than-HD resolutions. If you try to use a cable longer than 5 metres, your display will automatically drop down to 1080p simply because it has run out of bandwidth over the longer cable.
Fire emblem fates revelation citra. See our 5 metre DVI-D Dual Link cable here!

Because DisplayPort was so ahead of its time in terms of bandwidth and resolution capability when it was launched, strict limits were set on what cable lengths could be certified. This decision limited confusion in the market place, but set the maximum limit for a certified DisplayPort cable at 5 metres.
See our longest DisplayPort cable here!

Using couplers to join two certified DisplayPort cables together for a run longer than 5 metres will result in loss of signal. There is currently no workaround for this length limit.

Like Dual-Link DVI, VGA accommodates many resolutions, each of which requires a different amount of bandwidth. As cables get longer, the available bandwidth decreases and with it the highest potential display resolution is lowered. A short VGA cable can manage 1920x1080 without trouble. A long VGA cable may top out at 1024x768, and our longest offering may struggle to reach 800x600.

• Basic VGA: For a single cable, it's always important to consider your requirements and the installation environment before opting to use a VGA cable over 5 or 10 metres. But if resolution isn't an issue, we stock all the way up to 40 metres.
  See our longest VGA cable here!

• VGA over CAT: To overcome these limitations, we carry a VGA over CAT5/6 Extender kit. With this sender/receiver pair, bandwidth is boosted considerably – allowing for 1024x768 to reach 75 metres, and 640x480 to reach 300 metres.
  See our VGA Extender kit here!

The new SuperSpeed USB standard has its own set of rules for maximum length, so we'll look at each standard separately. Because of its age, USB 2.0 has more workarounds on the market than USB 3.0, but come with some important caveats.

• USB 3.0: Extra pins. Higher speeds. More bandwidth. The ability of USB3.0 to achieve these accolades relies on the cable most of all, yet the USB 3.0 standards don't specify a maximum cable length. However, our testing has shown that there is a definite failure point for USB 3.0 (especially when using portable hard drives). For devices requiring power over USB, 2 metres is foolproof. For self-powered devices using an internal battery or direct wall socket connection, we carry a 3 metre cable.
  See our longest USB 3.0 A/B cable here!

• Basic USB 2.0: It's everywhere. From flash drives to digital cameras and from portable hard drives to printers, you can't escape USB 2.0! Because of its ubiquitous nature, USB has to be a Jack of All Trades in terms of power delivery and bandwidth. As such, regular USB 2.0 cables have a limit of 5 metres to meet the certification standard. You can go longer with USB extensions, and data may still get through, provided that the device (hard-drive, printer, etc) is independently powered.
  See our longest USB 2.0 A/A cable here!

• Boosted USB 2.0: We stock two lengths of USB 2.0 cable which feature integrated repeater/booster chipsets, both of which can be daisy-chained repeatedly. The downside to this method is that the 5v power rail is used for boosting, and is therefore not available for powering a connected device – great for printers plugged into mains power, but not so good for portable hard drives. Our boosted USB 2.0 cables come in 5 metres and 12 metres, and can be chained together for runs up to 36 metres!
  See our longest Boosted USB 2.0 cable here!

• USB 2.0 over CAT: Based on a similar principle to HDMI over CAT, USB 2.0 can also be greatly extended using a Cat5 or Cat6 cable. You'll experience the same limitation on USB-powered devices as the booster chips above, but a good link can get your USB 2.0 signal to go 80 metres.
  See our USB 2.0 Extender kit here!

• USB Hub Daisy-Chaining: It may be possible to string together multiple powered hubs to extend the range of USB 2.0 and/or USB 3.0. So long as each hub gets it power from an external (non USB) source, it is theoretically possible to exceed the above length limits. We haven't tested this ourselves, so we don't know what the limit is..
  See our Powered USB Hub here!

Toslink (optical SPDIF) relies on a pulse of light to operate, and as such doesn't suffer from signal loss due to electromagnetic or RF interference. It is also unaffected by electrical resistance, but there are two important aspects which play a role in length limitations: The clarity of the optical core inside the cable, and the strength of the light source inside the hardware.

Toslink cables intended for consumer-level use contain plastic optical fibres. This makes them robust, flexible and great for lengths up to 15 metres - provided that the source device has a strong enough output.
See our longest TOSLINK cable here!

It is possible to track down Toslink cables that have glass fibre cores. These cables can potentially go much, much farther than plastic, but their fragility and extreme cost make them unworkable (and unnecessary) for most homes. If you are finding that a 15m TOSLINK cable is failing, it's more likley the source device is too weak rather than the cable being faulty.

Analogue formats bear a unique burden in that there is no parity check to ensure that the display device is receiving uncorrupted data. Coupled with the simpler technology which powers these standards, they suffer greatly from signal loss over long lengths.

Put simply, the farther you go with analogue, the worse it looks or sounds. Sure, you can run a 50 metre component video cable (if you could find one) but the quality of the image at the far end would be horrible. It's here, with analogue, that cable quality matters most.

• CVBS & YPbPr Video: Our longest length in these formats is 20 metres, but your mileage will vary greatly between our cheapest and most expensive options. If you want a crystal-clear signal over the longest length, only Amped Onyx can provide the best signal, and after that it comes down to your environment and source quality.
  See our best and longest RCA Video cable here!

• 2RCA Audio: Analogue audio can be more forgiving than its video counterpart, but cable quality still has a profound affect over longer lengths. With 2RCA, you can easily go 30 metres.
  See our longest 2RCA cable here!

• Audio Mini Jack: With 3.5mm audio, Cable Chick stocks a maximum length of 10 metres. Why? Because 3.5mm cables are most commonly used for personal headphones where any dips in audio quality become very apparent. Yuck! While we don't stock pre-wired 6.5mm audio cables (at the moment) using an adaptor works just as well over the same 10 metres.
  See our best and longest 3.5mm Mini Jack cable here!

Bare Speaker Wire (the kind which is just twisted copper strands in a PVC sheath) is a special case among all of the cable standards we'll discuss here. Because amplifiers and home theatre receivers can have different power ratings (watts and ohms) the cable itself has to be capable of carrying a range of power levels without overheating and catching fire. A beefy thousand-watt amp driving big speakers through thin wire will get you a visit from the fire department quicker than it'll give you good sound.

Cable Chick currently only stocks 16 AWG and 12 AWG speaker wire. 16AWG is a great baseline because it's the thickest gauge that can easily fit into the spring-clips found on most entry-level home theatre and audio gear. 12AWG is just over double the size, and it caters to pretty much everything else you'd be willing to put in your home. If you're looking at a sound system which needs heftier cable, the police will be responding to noise complaints before you get to stretch its legs!
See our 16 and 12 AWG Speaker wire here!

In terms of length limitations, we've adapted this handy chart to give you an idea of what's possible. Remember that most home theatre speakers are 8 Ohm, so always be sure to match your amp to your speakers when purchasing components separately. It's vitally important if you don't want to blow your speakers that both the Wattage and the Impedance are identical.

Serial Cable Maximum Length Comparison

In Summary

So there you have it! Our crash-course in cable lengths. We realise this isn't a definitive guide, but for the sake of simplicity we didn't discuss solutions we can't source, or that fall under industrial or commercial applications. If in doubt, always use the shortest length of cable you can live with, and for cables like HDMI and DisplayPort, ensure they're certified by the industry bodies which control them before purchase (ours are!).

Serial Cable Maximum Length Weight Chart

And of course, what kind of article would this be if we didn't have a huge chart with all of this info in one hit?

Still stuck?

There are some standards we haven't covered here – like microphone leads – mainly because we anticipate customers will have some prior experience when working with them. But if you still have a burning question, simply fill in the enquiry form on our Contact Us page and we'll do our best to help you out!

Maximum Length Of Serial Cable