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Old 10-13-2005, 08:42 AM
oldred oldred is offline
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Toy, A word of caution here, I have been very disappointed lately to see a reputable company like Ingersoll Rand get into this "peak" HP nonsense because it is totally misleading and just plain dishonest. I think maybe it is the retailer and not IR themselves that are doing this but be warned that 11 HP "peak" is total nonsense and the real power out put is a great deal less than that. Both units appear to have the same pump/motor combo so the 5 HP claim seems a lot more believable but that CFM rating is a Little suspect for a single stage so before you buy make sure that it is the SCFM and NOT that ridiculous "tank assisted CFM" that some have resorted to using lately. You simply cannot use some manufactures specs to get a meaningful idea of how your compressor will perform because they go to great lengths to mislead the customer into thinking he is getting more than he really is. The way to determine the REAL power output is to look at the AMP rating (running, NOT start-up!) a real 5 HP motor will be rated at around 28 AMPS and if it is only about 15, as most single stage units are, then it is only about 3 1/2 to 4 HP no matter what ridiculous numbers they claim! HP does not determine a compressors performance anyway so the important thing to look at is the SCFM output since, when all else is considered, the CFM is really what matters because if the CFM is low NOTHING else will make up for it. The problem here is that now these outfits have resorted to using this "tank assisted CFM" scam which tells you absolutely nothing except that they are being dishonest about their numbers. The bottom line is look at the SCFM rating, the AMP rating and overall quality of the outfit and ignore all those impressive but phony numbers. Also a 60 gallon tank is all you need and while an 80 gallon will offer some advantage in compressor life and power consumption due to fewer start-up cycles this is only a very slight advantage and not worth spending much extra money on. As has already been said many times before an 80 gallon tank vs. a 60 gallon offers NO performance advantage in spite of what you will be told and if you pass up a unit with a smaller tank but more CFM to get the 80 gallon you WILL LOSE performance because CFM runs your tools not the tank and a bigger tank will not make up for insufficient CFM and don't let anybody tell you that it will!
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