KOA Creations

Archive for January, 2012

While trying to get a spot in any of the expeditions organized by Wilderness Ventures, it is very important to understand precisely how this whole process works. First of all, you must make sure you got the right trip. They are split into multiple categories, for various types of participants. At the same time, you have to move fast. The spots are limited and the demand is huge.

 Wilderness Ventures definitely has a huge reputation and some amazing standards for high quality, therefore people often aggregate to get a spot. Now, once you get on board, things suddenly become easier. Whether you already have friends in there or not, you will easily make new ones. The most complicated part is during the enrollment process. This is the part where most kids have a lot of questions in order to decide whether they want to go on or not. They freak out about their new mates, while they wonder if they can get along fine or not.

 Although it doesn’t seem too important for many, a lot of kids care for the male/female ratios. Too many girls and a few boys will make it awkward for them. Fortunately for the social considerations, the ratio is close to one to one. Although the numbers are not always precise, the general idea remains the same. As a matter of fact, there are no other companies that put so much importance on these ratios like Wilderness Ventures. The age is also a questionable aspect. Parents wonder if their kids will be grouped with other kids their age. This is one of the most important aspects to ensure a proper experience for children. They are always grouped by the age and then by their preferences and hobbies, in smaller groups.

 What about more friends going on the same trip? If kids are too shy to go on their own, they can also embark upon these expeditions with a few of their friends. However, this means more applications and the results may not always be positive, but such cases are rare. If you wonder where the kids come from, all the states are successfully covered. Actually, within the last few years, only two states had no representatives. Meanwhile, close to 5% of the students joining Wilderness Ventures come from out of the United States of America. This is how far the program has reached. Other than these small aspects, the enrollment program is piece of cake.

Have you ever wondered why some power ratings are expressed in WATTS, some in AMPS, some in VOLTS, and some in KVA? For many in the hosting business this can be a very confusing topic. Face it, professionals in the content business are probably not electrical engineers, and most electrical engineers know nothing about the creation and delivery of content.

This article will explain in simple terms the difference between the major power ratings, and describe when each should be used in your network architecture planning.

According to APC, the main difference between watts and volt amps is the watt rating determines the actual draw of power from a power source and the heat generated from equipment. The VA rating is used for sizing equipment such as circuit breakers, wiring, and UPS. The VA rating is normally equal to or higher than the watt rating, as it includes the “power factor” in its calculation.

Power Factors

The Power Factor is a calculation used to account for the difference in power supplies used to convert AC power into DC for use in electrical appliances and computer equipment. There are two types of power supplies – the capacitor input supply and the power factor corrected supply.

Power factor corrected supplies are used in most high end computing and switching equipment, and have a ratio of 1VA:1W – allowing a very simple calculation for scaling electrical equipment and UPS. Thus, in theory, if your power factor is 1:1, and your UPS is an 80KVA UPS, then you would be able to load the UPS to 100% of its rating.

Older electrical equipment, as well as most lower end computers and video equipment use capacitor input power supplies and have a power factor anywhere from.55 to.75 times the VA rating.

Typically when scaling a UPS for use in a data center you will use a 60% load factor on the UPS. If you overload a UPS it is almost certain to fail during a power outage, as the draw on the batteries will exceed the capacity of the UPS. Most new UPSs will automatically go into battery bypass when an overload condition occurs. The 60% load factor accounts for the high probability that most of the equipment drawing power through the UPS will be of a category that has a power factor of between.55 and.75.

Example 1

You have a 10KVA UPS. Your data center has racks of low end self-assembled computers with a total estimated rating of 9000 watts. Your UPS will most like fail, as the power factor is probably around.70. You would need at least 12.85KVA to adequately backup the data center.

Example 2

You have a 10KVA UPS. Your data center has racks of low end self-assembled computers with a total estimated rating of 6000 watts. Your UPS will be able to handle the load, as the power factor corrected rating will require approximately 8.5KVA of UPS.

Some modern UPSs will actually tell you the average power factor and real time load capacity of the UPS.

Some Useful Conversion Factors

o Refrigeration

- 1 watt =.86 kcal/h

- 1 watt = 3.412 Btu/h

- 1 watt = 2.843 x 10-4 tons

- 1 ton = 200 Btu/min

- 1 ton = 12,000 Btu/h

- 1 ton = 3,517.2 W

o kVA Conversions

Three phase

kVA = V