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Products Similar to Cycle Stop Valves
There are several products on the market that try to accomplish the same task as
the patented non closing design of a Cycle Stop Valve. Many valves are available
with fully closing valve seats using a small hole or bypass tube to allow for cooling
of the pump or motor and for filling of the pressure tank. The small hole or bypass
tube can become clogged with debris or grow closed same as the holes in your
shower head causing overheating and destruction of the pump or motor. These
fully closing type valves can also cause water hammer or pressure waves when the
valve closes fully or when it pops open from the closed position. Some valves use
speed controls to reduce the pressure waves by slowing the opening and closing
speed of the valve. These speed controls can keep the valve from reacting fast
enough to keep up with changes in the field. If the control valve does not react as
fast as the flow rate in the field changes, the pump can be bounced on and off
several times while the valve is catching up. Franklin Electric or Jacuzzi®, now
called Franklin Pump Company makes the Aqua Genie 400®. Flexcon® industries has
a valve called a Smart Tee or Smart Tank. Red Jacket Pumps® used to make a valve
called the Hydroservant®. The new Hydroservant®, which will be discussed later, is
now a variable speed drive not a valve. Danfoss Flomatic® makes a fully closing
control valve which is called a Cyclegard® and is in no way related to the patented
non closing Cycle Stop Valve.
Danfoss Flomatic® as well as Cla-Val®, Watts ACV®, Bermad®, OCV®, Dorot®,
Raphael®, Netafim®, Zurn-Wilkins®, and Senninger®, all make check valves and fully
closing control valves that do not have the same control characteristics as a Cycle
Stop Valve. See (Cycle Stop Valves verses Fully Closing Pump Control Valves)
Variable Frequency Drives or (VFD) are also known as Variable Speed Drives (VSD),
Adjustable Speed Drives (ASD), Variable Speed Pumps (VSP), Adjustable
Frequency Drive (AFD), Frequency Inverters, Inverters, or just Drives. These
electronic devices will reduce the RPM of a motor and pump to try and match pump
output with the demand. Head is reduced by the square of the RPM which limits
the usefulness of these devices. Claims of energy savings are greatly exaggerated
as the pump is not able to be slowed enough to save energy. Slowing the RPM by
more than 10% reduces the head produced to a point where the pump is no longer
moving any fluid. Although we may expect beneficial technology to be electronic,
this is not always the case. The same job and energy efficiency can be
accomplished without the use of electronics buy using a Cycle Stop Valve, which
makes a water supply system simpler and more dependable. Many companies make
drives such as the Franklin CP Water®, Franklin Monodrive®, Grundos SQE®, ITT
Goulds®, Goulds Aquavar®, Goulds Aquaboost®, Goulds Hydrovar®, Goulds
Technovar®, Goulds Pump Smart®, Red Jacket Hydroservant®, Pentair® Pressure
Controls or Pressure Central® (PPC’s) (BPC)®, ABB Drives®, Allen Bradley Drives®,
Squared D Drives®, Altivar®, Danfoss Drives® and others. Packaged pump systems
using Drives are also made by Flotronics®, Watertronics®, Syncroflo®, National
Pump VFD®, Tigerflow®, Grundfos Boosterpac®, Peerless package systems®,
Pacoflo®, Paco Miniflo®, Rainbird Pump Station® and others. See also (What they
don’t want you to know about Variable Speed Drives) and (Cycle Stop Valves verses
Variable Speed Drives)
MagnaDrive® and pumps with automatic transmissions have variable speed
characteristics without many of the negative side effects. The motor is spinning
at normal speed and running on standard voltage and frequency while the pump is
slowed to match the usage. Transmissions waste or burn energy. Magnetic
couplings must be controlled with electronics and pressure transducers which can
cause problems. Magnetic couplings can be expensive and require a certain amount
of space which restricts their use for installations with limited space such as
submersible pumps. As with the Variable Frequency Drives, these devices also slow
the RPM of the pump which causes head to be reduced by the square of the speed,
limiting their usefulness on pumping systems that require a certain head to operate
correctly.
Other types of devices such as Mascontrol® or Prescontrol®, Davey Pressure
Booster Systems® ,and Franklin Pump Aqua Genie 80®, are flow switches and time
delay. These devices turn the pump off when there is no flow and restart the
pump at a lower pressure. Unless used with a pressure reducing valve these
devices have no control over the pressure, meaning full pump pressure may be seen
in the distribution system. Small flow rates or leaks in the system can cause the
pump to cycle on and off rapidly. Small centrifugal and jet pumps may be able to
tolerate this cycling abuse for a short while but larger pumps and submersibles will
not last very long when cycling rapidly.
Systems using a pressure tank and pressure switch as the only controls such as the
Amtrol Pressuriser®, cycle according to the pressure tank size. Larger tanks
reduce the number of cycles but do not stop destructive pump cycling.
In systems that pump fairly cool and fairly clean water, nothing beats the
simplicity and reliability of a Cycle Stop Valve.
The Cycle Sensor is a motor protector that was designed to work with a Cycle Stop
Valve. This device looks for dry run conditions and sees rapid cycling as a fault and
shuts the pump off. The Cycle Sensor has a fully adjustable underload setting
which can be superior to many other protectors on the market such as Symcom®,
Pumptec®, Coyote®, and The Protector SPS®, and Franklins Sub Monitor®
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