Australian Partners visit UNIPOWER Europe

On 12th and 13th October the staff at UNIPOWER's European office welcomed four members of the team from our agent in Australia for a two days of product training.

Delia Jones, Ian Hansen, Malcolm Scott and Bryan Cook took a detailed look at UNIPOWER's comprehensive range of power conversion product as well as delving into the depths of the software features that many of these now offer.

"Our time at Unipower was friendly and relaxing; but above all a very informative time. Being able to meet with the guys on a face to face basis we learned a great deal," said Dewar General Manager Ian.
"The product knowledge we gained could not have been achieved without visiting UNIPOWER and we feel we are now in a great position to ensure our customers in Australia and New Zealand make the right choice when selecting a vendor for their power requirements.
There was one moment of tension however when we were challenged to a table tennis match. We did manage to hold our own against some stiff competition and didn't let go of those particular ashes!"

Supercomm 2009

UNIPOWER will again participate in Supercomm this October in Chicago.

This will be the 9th time that UNIPOWER will be an exhibitor at this important show. The company will again return with an updated and refreshed 10 x 20 booth, that can be found in location 5025.

This year the company will present new products that represent the company's new focus on providing standard integrated power systems and also its ability to configure and integrate many of it's standard power components into "one of a kind" solutions for customers looking for fast and easy to install power solutions.

Highlighted at Supercomm will be UNIPOWER's new Bluestreak Rectifiers, a series of high-density, high-efficiency modules that boast 92% efficiency. These rectifiers will be also found incorporated in the new Gravitas X200 Compact System as well as in its Gravitas X450/X650 Power Cabinets.

Along with these systems the company will show examples of its pre-configured AC backup systems that include battery chargers, inverters, transfer switch, comms module and even various distribution possibilities. These systems ship all in a single box and once easily connected can be up and running in a matter of minutes.

We look forward to seeing our customers and friends at Supercomm, Booth 5025.

Battery Protection in Telecomn Systems

Battery Protection in Telecom -48V Rectifier Systems

In telecom power systems using battery backup, the battery size in Ampere-Hours(AH ) is determined by the maximum system load in amperes and the backup time in hours to maintain the system output voltage within acceptable limits during an AC power failure.
Generally, for battery backup requirements exceeding 1.0 hours, multiple battery strings are required. These strings are connected in parallel across the 48V bus and each string should carry it’s equal share of the total system charge and discharge current. During the discharge time the battery supplies the total system load. Each battery string must be rated to supply a current equal to the maximum total system load divided by the number of battery strings. It is good practice to use circuit breaker protection in each string to provide overload protection, and this is also useful in providing a method for manual disconnect for each individual string for maintenance and service. It is recommended to rate the circuit breaker current at a minimum of 25% above the maximum string current as defined above.

During the charge time, after AC power is restored, the battery will be recharged at a current equal to the total rated rectifier current capacity minus the total system load. It is important here to ensure that there is sufficient rectifier capacity beyond the system load to meet the recharge time requirements. In most systems the recharge time requirements are typically substantially longer than the discharge time requirements at maximum system load, and as a result, the battery current during recharge will be lower than the battery current during discharge. Therefore, circuit breaker protection defined for the discharge protection should be satisfactory for the recharge protection.

Custom Powersupplies

EASYMOD switchers are 40W to 350W single and muiltiple output units which are available with Industrial and Medical approvals with both AC and DC inputs.

EASYMOD simply means, "IF WHAT YOU SEE IS NOT WHAT YOU WANT, IT CAN BE EASILY CHANGED".

The philosophy of the EASYMOD product family is one where the design is flexible and allows for key features such as output voltages and current ratings to be tailored to meet your specific requirements WITHOUT the need to re-submit for agency approvals; and we can do all of this for programs requiring as few as 250 units per annum.

EASYMODs include: extended temperature operating range (INDUSTRYMOD), isolated outputs, unique output combinations, DC input, low noise versions and much more.

Next time you ar looking for a 40W to 350W switcher that does exactly what you want it to do give us a call.

High Efficiency Powersupplies

UNIPOWER Corporation announces its latest generation of high-density, hot swappable 48VDC modular rectifiers and front-ends. Called BLUEstreak™, the series combines high power density with high efficiency levels. The Front–end version will be factory set at 48VDC while the Rectifier version will be set at 54.4VDC.

BLUEstreak units can provide up to 2000W from a 1U high package at power densities as high as 23.4W/in³. Input voltage range is between 85 to 264VAC . Efficiency levels to 92% at 75% load. Four units with a total output of up to 8000W can be housed in a highly flexible 1U system rack.

The modules feature automatic load sharing and output Oring diodes and have an operating temperature range of –20 to +70ºC managed by variable speed cooling fans. LEDs indicate AC and DC power good and two standby outputs are available, +5V @ 1.8A and +12V @ .8A.

Like other UNIPOWER rectifiers, BLUEstreak modules use the I²C based PMBus to pass status and control data between a host system, management unit, and the module.

BLUEstreak rectifiers and front-ends will find wide application in network equipment and data storage as well as in telecom battery systems and will be available from end of Q2. The Series will include additional output voltages and various power levels in the near future.

How to evaluate the benefits of higher power supply efficiency.

In a push to improve the use of our resources, there are a number of industry and governmental initiatives with the goal of providing products and services in environmentally friendly ways. One of the techniques in the electronics and computer industry that can show almost immediate benefit is to improve the electrical efficiency of the power system. Every electronic system has to have a source of electrical power. Typically the power is derived from the AC mains or from banks of batteries. In almost every case, there is a need for an electronic converter that will take in this raw electrical power and convert it to a well-regulated, low voltage DC level that can be used to power the electronics. The efficiency of this electrical conversion process is defined as the ratio of the output power to the input power. The output power is measured in watts, and can be calculated as the product of output voltage times output current in Amps. The input power is also measured in watts, and is also the product of input voltage times input current. If the input is provided from an AC (50 or 60 Hz) mains, the modern power converter will include a processor that will correct the input current so as to be a sine wave, in phase with the input voltage wave. This process is called power factor correction, and ideally provides a sine wave of current that is 99% pure sine wave.

To understand the impact of efficiency, it is useful to look at an example. Figure 1 below shows a chart that gives the input power(Pin) and the output power (Pout) at different output current (Iout) levels for a high efficiency power converter. The efficiency is calculated by dividing output power by input power and listing the result as a percentage. We can also compute the internal power by subtracting the output power from the input power. This is the power that gets dissipated inside the power converter, and is undesirable. This power is wasted in the power converter. It heats up the converter and serves no useful function. Ideally this number would be as low as possible.



There are several interesting features shown on the chart. If we make a graph of internal power versus the load current, it will look like Figure 2. It shows that even with no output current, there is some internal loss inside the power converter. This is generally the power needed to run the cooling fans and provide power for the internal circuits in the converter. Then, as the load is increased there is a gradual increase in the internal loss until we reach, in this case, a level of about 10 amps, and then the internal loss goes up on a steeper curve. This effect is due to the resistive losses in the input and output sections of the converter, and they come to dominate the internal losses as the load increases. The two conclusions that may be drawn from this data is, first, there is a loss at even no-load, which is encountered when the electronics goes into a ‘sleep’ or ‘hibernate’ mode. If even less dissipation is required in this mode, it is possible to inhibit the power supply and turn off the fans and selected circuitry. Secondly, at lower load levels, there is a load range where the internal loss does not increase very much. If indeed the expected loads will be only at low levels, the electronic systems designer should consider re-sizing the power supply or evaluating what the best trade-off would be in terms of providing redundancy in the power systems. There is an ‘overhead’ energy cost associated with redundancy and this should be balanced against the added system reliability advantage that comes with power redundancy.



The chart presented in Figure 1 is taken from measured data on a new, high-efficiency, AC/DC power supply that is optimized for higher efficiency. To understand the cost benefit of this higher efficiency, refer to Figure 3. In this chart, we compare the difference in internal power between the high efficiency converter and a standard one with an efficiency of 80%. The difference between these two converters is shown as the line on the chart with a diamond-shape marker. It represents how much more power is wasted in the less efficient converter at different levels of output loading.

As an example, at a output loading of 30 amps, which corresponds to an output power level of 1632 watts at 54.4volts, there is approximately 268 additional watts of power dissipated in the less efficient converter. If this is powering a constantly on, 24 x 7 piece of equipment, what would be the cost of this wasted power? Electrical energy is costed in terms of a certain cost per Kilowatt-hour. Although cost per Kilowatt-hour vary around the world, let’s take a look at annual cost using a typical cost of $0.10/KW-hr.. In one year there will be a total of 268watts x 24 hr/day x 365 day/year x 1Kwatt/1000 watt = 2348 Kw-hrs/year of wasted power. Cost of this wasted power is 2348 x $0.10 = $234.80 per system per year.


Many users will find that the high efficiency power supply is a good choice, especially when powering critical electronic and computer applications. Although the original equipment manufacturer generally does not incur the operating costs associated with these types of applications, it is a useful feature that will make the efficient system attractive to the OEM’s customers. In addition to the reduced operating costs, the less electrical power that is wasted will show up in reduced cooling requirements for the end customer. Many datacenters, computer/server farms, and Telco equipment are loaded with electronic gear and the cost to cool the hardware is one additional operating cost that goes down when the power conversion efficiency goes up.

This blog was written by Vance Burns, Director of Product Development for UNIPOWER.

UNIPOWER at Electronica Show

In November of 2008 UNIPOWER once again participated at Electronica Fair in Munich, Germany. This Fair or Show comes together every other year and it is an important part of our European marketing effort. This Fair had 2800 exhibitors with an entire hall dedicated strictly to power supplies. The Show also brought 73,000 visitors from all over the world, with attendance from Easter Europe, South Africa and Latin America increasing this year.

For UNIPOWER it is all about making new contacts and spending time with friends and customers. This Electronica Fair, as some of you may know, is not like American shows, here you actually spend time sharing a beer or coffee with visitors while discussing product features or business points. This year we had a good number of visitors, mostly from Europe, though we also made contact with visitors from the Middle East, Asia, North America and Latin America.

We look forward to the next Electronica Fair in 2010, in beautiful Munich, Germany!

Supercomm Show 2009

Once again UNIPOWER will participate in Supercomm 2009 with its twenty foot display. The show, originally scheduled for June, has now moved to October 21 thru the 23rd, still in Chicago.

The company has been participating in Supercomm now for 10 years and we believe it is an important event for the company. First and most important is that it allows us to meet face to face with many of our customers. Another important reason for UNIPOWER to participate is to introduce new products and capabilities to the market at large. Every year we have something new to talk about and Supercomm is a great place to show our customers what new products we can offer them to make them to solv etheir problems or to make them more efficient or competitive in their markets. It is also a great place to get feedback on products and ideas for new generation products.

The show has changed over the years, with attendance fluctuating wildly from year to year. For us it is about meeting friends and customers and showing off our capabilities. We hope this year it ends up being a good show, as it would mean that it is a good year for our industry and that the economy has bounced back.

This year we plan on introducing a new generation rectifier system, featuring high efficiency and digital controls in an extremely dense package. More information on this product to come in the next few weeks.

See you at Supercomm in October!

High Altitude Power

Installations in hostile and high altitude environments are common in the telecommunications business. Sites are located in the most remote places and these require rugged power equipment that can survive the environment.

We thought it would be of interest to show a few photographs of some high altitude installations in South America using our equipment . These installations shown in these photographs are all well above the clouds as can be seen in these pictures and while they are very basic in nature, they still require very rugged equipment from UNIPOWER .

Soon we will be posting on High Altitude operation and derating.

"CHAT" FOR BETTER CUSTOMER COMMUNICATIONS

UNIPOWER uses "Chat" capability on its website to make communications with customers more efficient. By simply clicking on the "Chat Button" on any page on http://www.unipowercorp.com/ or on http://www.unipowertelecom.com/ , a customer can be in touch with one of our sales or technical support personnel and carry on a fluid, extended dialog.

Customers all over the world use Chat to contact us, as we are able to respond in several languages and provide coverage for 13-15 hours per day.

The ability to communicate in writing in a fast and fluid manner is the key to the success of this system. It is a great substitute for e-mail as there is instant response from the company. It is also a great alternative to voice or phone as it is free to the customer and again, there is instant response from the company.