How To Calculate How Much AC Power You Need After spending another sweltering weekend in my flat I knew it was time to replace the once-trusty window AC unit that had become not-so-trustyworthy. As I began a search for a replacement I tried to figure out just how many BTUs I needed for the space, wondering whether I needed an upgrade... When shopping for AC, in addition to the guidelines that Energy Star puts out (as shown in the chart above) there are a few other important things to consider: 1. The Shape of the Space: What kind of space are you looking to cool? In addition to looking at the total square footage you want to consider at how the space is laid out and if it contains any heat sources like an oven. In our railroad style flat, in order for the bedroom to be cool, the air would have to travel past the hot kitchen which means that a more powerful unit is required. 2. The Amount of Sunlight: Are you trying to cool a space with large windows that let in lots of sunny heat?

Best to get some shades to block some of that sun and factor the windows into your AC buying decision. A very sunny room requires the AC to work 10% harder to maintain the same level of cool. 3. Will the Cold Air Escape? Just as you would think about heat escaping in the winter, make sure to seal up any places where the cool air can escape. You don't want to spend money cooling the outside! A home that's not well insulated will take more AC to cool. 4. How Many People Will be in the Room? If you are looking for an AC for your room in which you host lots of gatherings thing about that when you're calculating how much AC you need. For rooms with more than 2 people regularly in them Energy Star suggests calculating an additional need of 600 BTUs per person. 5. Let Fans do Some Work: Properly placed oscillating fans can help cut down on how hard an AC needs to work to cool the room. Pick up some inexpensive fans and use them in the corners to help the cool air to circulate and you'll need less BTUs for those spaces that are a bit awkward to cool.

In the end, I settled for an AC that was slightly less BTUs then recommended by Energy Star and did my best to help the air to circulate with the help of some strategically placed fans. The new AC seems to be working out pretty well and and I'm quite happy I didn't wait till July to install it! (Images: 1, 3. Flickr members Brendon and Stefani Seskin licensed for use under Creative Commons, 2. Energy Star )If you require assistance with this Power Calculator or what generator will best suit your requirements, do not hesitate to contact us. Amperes when kVA is known Converting kVA to kW Converting kW to kVA Converting kW to HP kVA Required to run motors Calculating Ampere (I), given kVA What size genset is needed to start a 3 phase electric motor Direct onLine (DOL) start Generator Size to Start Motors Instructions: Fill in the HP of the motor(s) in their starting sequence, select the start method (DOL - Direct On Line or Star Delta) and

The required generator size will then be displayed at the bottom.should you cover air conditioner unit in winter 3 Phase (415 volt @ 50Hz)pump for ac unit 1 Phase (240 volt @ 50Hz)ac unit placement Generator Size for Starting with: Generator Size for Running with: * Please NOTE the above calculations are an estimate only because other factors such as site conditions, motor efficiencies and iron losses are not taken into consideration. For a more detailed answer and qualified advice, please contact us or give us a call on 03 9544 4222 (Melbourne), 02 9899 6699 (Sydney), or 07 3205 6333 (Brisbane). Power Consumption Calculator ApplianceRated WattsRated kVARated kVA (Appliances)(To operate appliance)( To start appliance)Air Conditioner (Evaporative model)275-10000.34-1.251.36-5Air Conditioner (Reverse cycle)200-25000.25-3.131-12.5Clothes Dryer240033Coffee Percolator5500.690.69Can Opener1000.130.52Deep Freezer5000.632.52Disposal Unit6500.813.24Dishwasher1000-30001.25-3.751.25-3.75Domestic Water Pumps275-10000.34-1.251.36-5Exhaust Fan400.050.2Food Processor5000.632.52Floor Polisher3500.441.76Frypan14001.751.75Hair Dryer15001.881.88Hotwater Service2500-30003.13-3.753-13-3.75Iron800-15001-1.881-1.88Kettle or jug1600-30002-3.752-3.75Lights25-2000.03-0.250.03-0.25Microwave15001.881.88Oven4000-80005-105-10Radio600.080.08Radiator1000-25001.25-3.13115-3.13Refrigerator (home)3000.381.52Sewing Machine600.080.32Space

Heater20002-52.5Television75-2000.09-0.250.09-0.25Toaster250-12500.3-1.560.3-1.56Washing Machine500-30000.63-3.752.52-15Welder 140A50006.258 min Please Note: Inductive loads (typically electric motors, electric pumps, electric compressors and air conditioners) require 6-8 times more current to start than to run. Most generators can provide 100% overload for start up purposes. A 1 Hp electric motor therefore will require 3-4kVA for start up. Once the 1 Hp electric motor has started, it will only consume 1 kVA leaving a extra 2-3kVA available for other appliances. However, the newer 'Inverter' style generators may be more efficient and capable of starting higher loads. Generator Selection The generator size must be equal or greater than the total consumption of all applications. The higher starting requirement must be taken into account accordingly. To maximise the generator potential, the largest electrical motor should be started on its own and further appliances should only be switched on thereafter.

Handbook of Electric Power Calculations, Third Edition A bestselling calculations handbook that offers electric power engineers and technicians essential, step-by-step procedures for solving a wide array of electric power problems. This edition introduces a complete electronic book on CD-ROM with over 100 live calculations–90% of the book’s calculations. Updated to reflect the new National Electric Code advances in transformer and motors; and the new system design and operating procedures in the electric utility industry prompted by deregulation. Title: Handbook of Electric Power Calculations, Third EditionPublisher: McGRAW-HILL: New York , San Francisco, Washington, D.C., Auckland, Bogotá, Caracas, Lisbon, London , Madrid, Mexico City, Milan, Montreal, New Delhi, San Juan, Singapore, Sydney, Tokyo, TorontoCopyright / Pub. Date: 2001, 1997, 1984 The McGraw-Hill Companies, Inc.ISBN: 9780071362986Authors:H. Wayne Beaty is the former managing editor of Electric Light and Power and editor of McGraw-Hill’s Standard Handbook of Electrical Engineering, Thirteenth Edition.Description: