Power Over Ethernet In Industrial

The pursue for PoE started decades ago. At first, Voice over IP needed power from a separate source. The simple DC power of Plain Old Telephone Service was missed. PoE answered the question of how to provide power and data over a single cable, simple and dependable. The reliability and cost effectiveness of providing both data and power over a single cable is improved with PoE and it has become a clear choice in multiple applications.
PoE was a missing feature that has now found a home in industry. It is an elegant technical solution. As Ethernet-TCP/IP has become common in control rooms and network backbones and access links, PoE has expanded the use of Ethernet on the factory floor.
By employing PoE technology in an industrial setting, users have the ability to supply redundant power to many sensors without having to provide a local outlet. Without PoE, the sensors are passive and data needs to travel long distances (up to 100 meters) to the point of control or a local power source must be installed to drive the sensors. With PoE a redundant power source can be used to power all the sensors through the single existing Ethernet cable without the trouble of installing multiple power sources all around the factory floor.
Now there is no technical reason that Ethernet cannot reach and power most industrial devices. Here are some of the options available for powering PoE and benefits that are motivating the adoption of PoE in industrial applications.

1. Speed:
PoE costs less than fibre and is delivering higher and higher data speeds. Data delivery rates are now at 1 Gbps (10/100/1000 Mbps) over Cat5e and Cat6. The new IEEE 802.3bz standard has the capacity to deliver speeds of 2.5 to 5 Gbps over 100m with an immediate view toward 10 Gbps. PoE has more than enough data speed to support devices in a small LAN.

2. Power:
PoE does not require an additional power supply, as data and power are supplied altogether over one cable. The previously developed standard—IEEE 802.3at—provides 30.8W of power. The most recently developed standard—IEEE 802.3bt—provides 60W of power.
3. Safety:
PoE is a safe power solution. Maximum voltage is under the limit for “high voltage” applications. To avoid damaging devices or accidental contact with even this relatively safe level, the PSE (Power Sourcing Equipment) sends a 10-volt test current to verify there is a 25ohm resistor at the PD (Powered Device) before full power is applied. If the PD stops using power, power from the PSE stops and testing resumes. Over-current, under-current and fault protection are also part of the PoE standard.

4. Flexibility:
PoE is standards-based, so interoperability across vendors is guaranteed. All variations of network topologies can be configured with PoE, including ring, mesh, and other networks. Plus, industrial network management tools such as RSTP/STP, IGMP and VLANs are available on the high quality industrial PoE switches. Single-cable power and data delivery, typical in fieldbus networks, is available with PoE. Plus, configuration changes on the factory floor are made simple by PoE. It just makes sense to do it with a single cable instead of two, where possible.

5. Reliability:
PoE is one means of providing power source redundancy. When added to the ability to configure Ethernet for redundant data configurations, it’s a powerful combination. The complexity of combining various networks often requires more equipment, programming, and maintenance. A single network is simpler and has real advantages.
6. Responsiveness:
PoE devices adapt to changing environments, as they can be easily moved and reconnected at the switch level and easily integrate into changing network configurations. PoE is plug and play, an entire network doesn’t need to be brought down to add or subtract devices.

TOP 7 CONSIDERATIONS FOR FIBRE OPTIC CABLE INSTALLATION

TOP 7 CONSIDERATIONS FOR FIBRE OPTIC CABLE INSTALLATION

With the development and implementation of 5G, optical fibre technology is now seen as the future of connectivity. To keep this connectivity at the speed of light it is important to pay attention to the rules of fibre optic cable installation. Therefore, we have put together a list of seven important factors to consider.

  1. MINIMUM BEND RADIUS

For fibre optic cable installation maintaining fibre optical cable’s minimum bend radius during installation is a significant factor. In many cases, as compared to the installation of UTP cable in the horizontal or coaxial cable, optical fibre installation is much easier.

Bending the fibre cable tighter than the minimum bend radius may result in increased attenuation and broken fibres. When the bend is relaxed and if the elements of cable are not damaged, the attenuation should turn to normal.

  1. MAXIMUM TENSILE RATING

During fibre optical cable’s installation maximum tensile rating should not exceed as per the values specified by the manufacturer. When a mechanical pulling device is used tension on the cable should at all times be monitored.

Circuitous pulls can be proficient through the use of back feeding or center pull techniques. For indoor installations, at every third 90° bend, pull boxes can be used to allow cable access for back feeding.

  1. MAXIMUM VERTICAL RISE

All optical fibre cables have a maximum vertical rise that is a function of the cable’s weight and tensile strength. This represents the maximum vertical distance the cable can be installed without intermediate support points.

Some guidelines for vertical installations include the following:

  1. All vertical cable must be secured at the top of the run.
  2. A split mesh grip is recommended to secure the cable.
  3. The attachment point should be carefully chosen to comply with the cable’s minimum bend radius while holding the cable securely.
  4. Long vertical cables should be secured when the maximum rise has been reached.
  5. CABLE PROTECTION

If future cable pulls in the same duct or conduit are a possibility, the use of an inner duct to sectionalize the available duct space is recommended. Without this sectionalization, additional cable pulls can entangle an operating cable and could cause an interruption in service.

  1. DUCT UTILIZATION

When pulling long lengths of cable through duct or conduit, less than a 50% fill ratio by cross-sectional area is recommended. For example, one cable equates to a 0.71 inch outside diameter cable in a 1 inch inside diameter duct.

Multiple cables can be pulled at once as the tensile load is applied equally to all cable. Fill ratios may dictate higher fibre counts in anticipation of future needs. One sheath can be more densely packed with fibre than multiple cable sheaths.

In short, for customer premises applications, the cost of extra fibres is usually small when these extra fibres are not terminated until needed. For a difficult cable pull, extra fibers installed now but not terminated may be the most cost-effective provision for the future.

  1. PRECONNECTORIZED FIBER CABLE ASSEMBLIES

The use of factory-terminated cross-connect and interconnect jumper assemblies is acceptable, the use of pre-connectorised backbone and distribution cable presents special installation techniques.

These connectors must be protected when installing the connectorised end of these cables. Protective pulling grips are available to protect connectors, but the grips outside diameter may prevent installation in small inner ducts or conduits. Before ordering factory connectorised cables the size of the pre-connectorised assembly and pulling grip should be considered.

There may also be additional installation requirements imposed on the grip by the manufacturer, in terms of minimum bend radius and tension, which would be the limiting parameters in an installation.

  1. FIBER OPTIC CABLE SLACK

A small amount of slack cable (20-30 feet) can be useful in the event where cable repair or relocation is needed. The slack can be shifted to the damaged point If a cable is cut, necessitating only one splice point in the permanent repair rather than two splices if an additional length of cable is added. This results in reduced labor and hardware costs and link loss budget saving.

When the drop is finally needed an additional cable slack (approximately 30 feet) stored at planned future cable drop points will result in savings in labor and materials.

 

Importance of Power Factor in Uninterrupted Power Supply (UPS) Solution

When choosing a UPS solution its power rating must be taken into account and it should match the requirement or else it could fail when it is needed the most. But unfortunately choosing the correct power rating is not as easy or straightforward as it may seem.
Power factor is a quantity which has important implications when sizing a UPS system and power distribution equipment. Power is a measure of the delivery rate of energy and in DC (direct current) electrical circuits are expressed as the mathematical product of Volts and Amps (Power = Volts x Amps). However, in AC (alternating current) power system, a complication is introduced; namely that some AC current (Amps) may flow into and back out of the load without delivering energy. This current, called reactive or harmonic current, gives rise to an “apparent” power (Volt x Amps) which is larger than the actual power consumed. This difference between the apparent power and the actual power gives rise to the power factor. The power factor is equal to the ratio of the actual power to the apparent power. The apparent power is expressed as the Volt-Amp or VA rating. Therefore, the actual power in any AC system is the VA rating multiplied by the power factor.
To size a UPS and ensure that the UPS output capacity is sufficient, both the VA rating and the Watt rating of the load are important. The watt rating of the UPS relates to the amount of power it can deliver, and the VA rating of the UPS relates to the amount of current it can deliver. Neither the Watt nor the VA rating of the UPS can be exceeded. The best approach is to size a UPS the Watt rating of the load. This is particularly true for larger IT installations where the power factors of the loads are nearly 1.
If there is confusion regarding power ratings or power factor, and it is desirable to ensure the load can be powered by the UPS, then choosing a UPS with a Watt rating greater than or equal to the VA rating of the load will always ensure a safety margin. Power factor has an important implication in the specification of UPS run time on battery. Battery run time is dictated by the watt load on the UPS. However, when many UPS manufacturers specify run time at full load they are referring to full VA load, not the full watt load.
Input Power Factor:
Input Power factor is the percentage of electricity that is being used to do useful work. It is expressed as a ratio. For example, a power factor of 0.72 would mean only 72% of your power was being used to do useful work. Perfect power factor is 1.0, (unity), meaning 100% of the power is being used for useful work.
Output Power Factor:
Output power factor rating is the percentage of electricity that is available to do useful work. For example, a power factor of 0.80 would mean only 80% of your power is available as real power to do useful work. Perfect output power factor is 1.0, (unity), meaning 100% of the power is available for useful work.

Conclusion:
Power factor is a major consideration when selecting a UPS, but unfortunately, it remains a misunderstood subject, and ignoring or misapplying the power factor concepts could result in a number of problems. It is really important to understand that if the ups cannot handle the real power and the reactive power consumed by the load, a situation can develop due to overload and that could quickly lead to UPS damage.

In-building DAS Network A Fundamental Amenity

In the in-building DAS connectivity world, progress is often viewed through the lens of enabling pervasive data connectivity for all employees working in a particular building at a given time. However, the impact of smart buildings and Internet of Things (IoT) in general, will have a potentially greater impact on in-building networking requirements going forward.

Although many building owners are starting to view the quality of their in-building cellular network as a fundamental facility, there is still a sizable sentiment within the commercial real estate industry that connectivity is a tenant and/or cellular service provider issue. As the Internet of Things (IoT) continues to proliferate, properties that do not have an adequate in-building network infrastructure to support applications and services in the 5G era will find it difficult to compete for tenants. Naturally, no one in the real estate ecosystem wants this to happen.  As the next phase of in-building wireless connectivity unfolds, below are few recommendations to help support new and/or ongoing deployments.

Large venues: Despite the fact that most airports, large malls, and entertainment venues have at least partial DAS installations and some level of public Wi-Fi connectivity, owners of these properties must take the next step. This includes becoming more aggressive deploying complete DAS networks that will offer a migration path to 5G. It also means working with an ecosystem of partners that will help deliver a premium experience to attendees.

Neutral Host investment models are needed: Although large, marquee venues can often attract a major wireless carrier to lead investments into DAS and other in-building connectivity solutions; there is a quick drop off in carrier willingness to invest in venues that do not fall into the “largest venue” category. In these cases – which represent approximately 95% of commercial real estate throughout the world – stakeholders need to consider Neutral Host Models that will help to spread the cost of comprehensive in-building networks among a number of investors that stand to benefit.

Technology providers must step-up to make investments count: If a material investment hurdle into next-generation in-building wireless networks is a fear on the part of building owners and/or tenants to invest in technology that can be rendered obsolete before the investments can be adequately depreciated, then technology providers need to work with investment stakeholders to ensure that investments made today remain relevant as the market moves towards 5G. In many cases, this means providing technology with logical and flexible evolution paths from the current state of the art to future developments (i.e. 4G/LTE to 5G). However, beyond this, it can mean working with building owners to help schedule investments in a way that creates attractive ROI models for both the short and long-term.

Passive Inertmodulation: An important factor to mitigate in DAS

PIM is described as a form of signal interference that can be caused by either metal components near Passives or two or more carriers sharing the same downlink path in a wireless network, which is becoming more common as wireless networks have become more complex with multiple technology generations such as 2G 3G, LTE and now we will be moving towards 5G. The signals combine to generate unwanted interference, which impacts the signal.
A lot of importance has been given to mitigate PIM nowadays, the reason being the increase in data usage especially indoors, has pushed operators to increase the spectrum for LTE Deployments, which calls for additional frequency bands combined into Indoor DAS by each operator. To stay competitive Telecom operators care a lot about user experience, and PIM is a big hurdle in providing the great user experience. The unwanted signals produced can degrade call quality and reduce the capacity of a wireless system.
High PIM means bad cellular connection and limited bandwidth to the end user, which in turn means lost customers for the operator. Low PIM means strong signals with more bandwidth for more users, which means happy customers and higher revenues for the operator. From a hardware perspective, it means that each and every connection must be designed to minimize PIM and tested to ensure it is installed properly.
Reports show that a slight increase in PIM value could have drastic impacts on downloading speeds. At this point, we should also consider what PIM value is usually acceptable. Well, the answer to that is it depends on which passive products are we talking about. For instance, the products that are close to the base station or the first passive component right after base station (POI, Splitter, and Coupler); -160dBC PIM rating is recommended because of the high power generation of the base station. On the other hand, the passive components that are far away from the base station -150dBC PIM rating would do the job too. By the time the signal reaches the antenna, the RF power is much lower, typically on the order of 100mW (20 dBm). Given the low power level and the high loss between the antenna and the signal source, it’s hard to believe that PIM generated at or beyond the antenna could possibly be high enough to impact system performance. Experience shows that due to the highly non-linear objects often found near antennas, harmful PIM is still possible. This is especially true at low frequencies (700 MHz, 800 MHz and 900 MHz) where the probability of PIM sources occurring inside the antenna’s near field increases. For this reason, PIM is still a concern at or beyond antennas in a DAS.
Regardless of the DAS architecture (Active or Passive DAS), there will be sections where PIM can occur. In a purely Passive DAS, everything beyond the operator’s radio is a place where harmful PIM can occur. With the many splitters, combiners, coaxial cables, and antennas required to distribute the RF signals, the possibility of PIM is in a large number of places. In the image shown below, there are over 150 locations where PIM could occur:
• 64 RF connections
• 31 cable assemblies
• 15 antennas
• 14 power dividers
• 1 hybrid combiner
• 1 RF termination

Linearity in Distributed Antenna System can be improved by using components that are factory tested for PIM, making sure all RF connectors are tight and clean, apply correct assembly torque, and locating antennas away from PIM sources such as pipes, lighting fixtures, and fans.