Q. How long have they made CAGI data sheets?
A. Since 2002.
Q. Can you expect to get exactly the capacity and power on the datasheet?
A. No, there is a tolerance on every datasheet. For instance on a machine between 50 and 500CFM, the compressor could have 5% less CFM than published and the specific power could be 6% higher than published. This is because it is impossible to make the machines completely equal, due to tolerances in the air end manufacturing and pressure drops in the system.
Q. What is specific power?
A. Specific power is a formula of how many kilowatts that it takes to produce 100CFM. The lower the number, the more efficient the machine.
Q. How are the machines performance verified?
A. The vendors are asked to send a certain amount of machines every year for testing. The machines are picked at random by CAGI out of the vendors stock. A competing vendor can ask for a specific machine to be tested, if they question the performance. I don’t think that has happened.
Q. Why would I care about the performance of older machines?
A. Because customers and utilities want to see comparisons to see if changing machines will save enough energy to make a payback available. Many companies are looking for a two to three-year payback.
Q. What archive datasheets does Fourth Utility Consulting have?
A. We have about 4000 CAGI data sheets, dating back to 2002. Most of the sheets are for Atlas Copco, Gardner Denver, Ingersoll Rand, Kaeser, Quincy and Sullair. We have 90%+ of all air-cooled machines between 50 and 500HP with pressures between 100 and 125PSI. We also have datasheets or the datasheet information on lower pressures, other brands and some water-cooled machines. The datasheets are for fixed speed and variable speed machines.
Q. How will we know that we have the most current datasheet on this service?
A. Because Fourth Utility Consulting will update the fixed speed and variable speed machines any time we notice changes or on a schedule as shown below.
Q. What products will be on the Fourth Utility Consulting website?
A. All vendors who are part of CAGI’s performance verification programs; machines between 20 and 500HP with pressures between 20 and 500HP. Fixed speed, variable speed and oil free comes to almost 1000 datasheets. For instance, Fourth Utility Consulting’s system allows you to see all brands of 125HP compressors on one sheet, separated by pressure first and then sorted by the best isentropic efficiency so the most efficient model will be on the top.
Q. Why doesn’t CAGI keep all the datasheets on their site?
A. Because they have no way of knowing when a vendor makes a change and it takes almost a full-time person to keep up with these changes.
Q. Does Fourth Utility Consulting have a schedule of updates?
A. Yes, we update fixed speed in July, October, January and April. Variable speeds are updated in August, November, February and June. Oil free machines are updated in September and March. If a major change happens, they will be updated as soon as that happens.
Q. What about datasheets for companies that were but no longer are in performance verification?
A. We have many of these datasheets in our archives, but they are not on CAGI’s form. They are on the manufacturers form and there is no guarantee that the performances are correct.