VFD's were introduced in 1968. Every year since, they have been adding new band-aids to try and solve the problems of last years model. The laws of nature cause many of the problems associated with VFD's. Continuing advances in electronics have certainly helped, but they will never be able to override the laws of physics.
Nothing can be done to change the physics of resonance frequency vibration. Voltage spikes to the motor and harmonics being fed back into the electric grid can be filtered somewhat, but not eliminated. Insulated bearings and shaft grounding just moves the problem of bearing currents somewhere else down the line. Then because physics dictates that head is lost by the square of the pump speed, most pumps cannot be slowed down enough to save energy.
High price and large profits is the main reason some people like to sell VFD's. However, this is about to change. VFD's have now become a commodity. There are many brands of VFD's available and some factories are now selling direct on line.
One thing that advances in electronics have accomplished is to make VFD's less expensive. Just like the calculators of the 70's, mass production and miniaturization continually reduce the cost of VFD's.
Now a home owner can purchase one of the best VFD's available for 150 bucks for a 1 HP pump. They can also purchase a VFD for a 100 HP pump for about $3500. These are top of the line VFD's, and other companies will soon be joining in on this price war. This will make it impossible for anyone to make a profit on VFD's. Anyone now promoting VFD for pump control is just shooting themselves in the foot.
You should realize that pump and motor manufacturers are not necessarily promoting VFD's to profit from them. Rather they promote VFD's because they profit from pumps and motors. VFD's shorten the life of pumps and motors and make it easy to plan how long a pump system will last, and how soon you will need a new one. "Planned obsolescence" is a primary goal of pump and motor manufacturers, and VFD's help them attain that goal.
Many manufacturers are now incorporating the VFD into the motor itself. On the pretence of making it better for the consumer, in reality this makes sure you have no choice. Being forced to purchase a pump with an integral VFD, insures you will need a new pump in a planned amount of time. Planned obsolescence keeps the cash flowing to the manufacturer. Unfortunately this cash is continually flowing out of the consumer's pocket.
Cycle Stop Valves are not made for planned obsolescence. The CSV will mimic the constant pressure performance of a VFD, without the negative side effects. CSV's are dependable, long lasting, save just as much energy as VFD's, and actually make pumps last longer.
No one will ever be able to solve the problems of VFD's, unless they can change the laws of physics.
For years many pump installers have enjoyed the high profit margins and short life expectancy associated with selling expensive VFD's or constant pressure pumps. Now that any home owner can purchase a VFD on the Internet for $150, the days of high profit margins are over.
Being able to compete in this economy will now mean offering products that do more, last longer, and cost less. Frivolous spending on gadgets that cost more and do less is a thing of the past.
Now more than ever simplicity, precise control, and dependability make the Cycle Stop Valve the best choice in pump control technology. Cycle Stop Valves, Inc. is dedicated to a distributor and dealer network that allows the installer to make the desired profit margin, while still offering the end user the ultimate in constant pressure performance at an affordable price.