Comment: Larger figures in electrical energy savings are probably based on a statistical average of applied motors' efficiency that may be low enough to make a statement that the Power Planner and similar ones save a double digit amount of electrical energy. When it comes to promotions, one just cannot flatly dismiss them based on ideal motor-load applications. There are motors that may be designed with peak efficiency at 50% of rated HP and others at 80% or rated HP. In fact, Power Planner sales figure seems to be confirming the above reasoning.
hi guys , sorry I have not answer before but I was away for some days from this interesting forum. now to you : Energyengineer
The unit I have tried is a P.P. III 60 amps unit and believe me I have followed very carefully the application and calibration procedure and no way I can get those high savings. why dont you tell us about your experience with the 35 units you mention in your post? , and I would appreciate very much any tips on how to improve the savings with the P.P.
Now to you GGOSS . It is true that one can get 5% savings . I measured with a Fluke power meter and the right way which is at the line side of the P.P. and not at the load side as the manufacturer recommends because that is WRONG and perhaps that could be one of the reasons why ignorant " engineers" think they get 10 to 30% savings ( they are recording wrong in the load side of the P.P. )
In many cases a few percent difference in motor efficiency between a standard motor and a high efficiency type is trivial when compared with energy wasted in the application.
The best applications for this type of controller tend to be pump with recirc. or a throttle valve downstream of the pump, or fans with dampers. In these cases the energy put in by the pump is lost across the regulating element.
Look at the whole application of the motor and load when deciding on energy saving devices.
OhOh Scotty, methinks you are refering to energy savings with variable frequency drives. This thread is about "energy savers" which do not vary the speed output, just the voltage. I just needed to make that clear for the newbies.
RE: Harry Dampers comment about why other major mfgrs don't push this. We did. In 1973 when President Carter's administration was passing out government rebate checks for anything that had the words "energy, savings and/or reduction" in the sales literature. The reality caught up with us later when the customers found out that unless their applicatoion was EXACTLY the same as the benchmark ap, the results were disappointing. My company decided 8 years ago to quit including it in our soft starters. It caused more dissapointment and ill will than it was worth. I think you are correct too in your statement about Rockwell having it in there just to keep themselves in the running when it shows up in a specification. I keep getting bumped out of project submittals because we don't have it and they do. In 99% of those applications, the same engineer specifies a bypass contactor as well, rederring the energy saver useless altogether! There is no limit to the depth which ignorance will drag some people.
RE: the OP's request for real applications. I used to be a Systems Integrator and applied many of them during those Carter years. I had success with only 2 applications: bowling pin resetters and a severelly oversized well pump. The bowling pin resetters run all day disengaged from the load by a clutch. When the pins get knocked down, the clutch engages for about 30 seconds and couples the load to the motor. The extreme unloaded time actually made it come out to be a true cost recovery device. Those are 1 phase by the way. The pumps were in Alaska and belonged to the Alaska Area Native Health Dept. Since the maintenance crews had to drive service trucks for days to get to villages, they only wanted to carry one well pump with them and use it at every site regardless of needed capacity; universal parts replacement etc. etc. In some villages, 30HP was adequate, but in others, 5HP would have sufficed. When they put the 30HP in a site that could only use 5HP, they trimmed the impeller and put on an energy saver to help reduce fuel consumption by the deisel gensets. I heard they eventually abandoned the program as too complicated. We tried them on wood chippers, turbine pumps, air compressors, vent fans, vacuum pumps etc. etc. etc. In all the rest of the applications the only benefits came from soft starting.
I could go on ad-nauseum (and perhapse have). These albatrosses have enjoyed a resurgence due to the internet. I hope it doesn't further damage the public's response to legitimate benefits of soft starters.
AAACK! I just realized what I did! By responding to this thread I just put the name Power Planner right back up to the top of page one again! Harry, I think you may be right about a carefully crafted marketing ploy! I only posted this because I already made the initial mistake. Please folks, quit responding so that this thread gets burried where these flim-flam devices need to be! Start a new thread if necessary (as if there aren't enough on this subject anyway), but PLEASE, lets not follow my example of guillable stupidity and perpetuate this scam!
