Industry News
New Pump Technology: Digital Level Control
by Joseph Sanchez
September 9, 2010
Romeoville, Ill.,-based Metropolitan Industries believes
that intelligent microprocessor technology represents a sea change over
mechanical switch operation in sump pumps.
Under development for several years,
Metropolitan’s patent-pending Ion Digital Level Controller eliminates moving
parts, which are the detriment of most mechanical switches, and replaces it
with solid-state sensing technology, which testing has shown to last 1.5
million cycles, approximately triple the
life of a mechanical switch.
“The problem was never the pump, because
they are generally built to last. The problem has always been the switch
responsible for the critical task of turning the pump on and off,” says John Kochan, Jr.,
Metropolitan Industries’ President, who developed the idea for the new product
by utilizing solid state components and applying them to switch technology.
While mechanical switches are useful and
function properly over a period of time, they are always subject to failure.
“Mechanical switches use moving parts and wear and tear in a sump pit
environment will always break those components down over time,” Kochan, Jr. says.
Switch failures translate into
non-running pumps, which can result in flooded commercial, industrial and
residential locations.
With the demand for reliable switches
evident with recent recalls put forth by some of the largest pump manufacturers
during the last decade, Metropolitan began work over a period of five years to
develop a product that can outperform mechanical switches in longevity and
dependability.
How It Works
The ION Digital Level Controller is a technologically
advanced device that senses water level/pressure through the use of a
proprietary sensor and microprocessor-driven digital control. The
microprocessor within the digital float sensor samples analog data from the
proprietary sensor, which electro-mechanically converts the water pressure to
an electrical resistance. Because water pressure is directly proportional to
the water height, the electrical resistance of the proprietary sensor is also
proportional to the water height. The resistance of the proprietary sensor is
measured by means of a resistive bridge network before passing into the
microprocessor’s analog to digital converter.
Traditionally, sump and sewage pumps
have been started by means of a mechanical switch. The mechanical switch design
often uses a set of electrical contacts that close under a given water height
scenario, thereby activating the sump pump. Due to the alternating nature of
the electrical voltage source from the utility, large voltage differentials
could possibly be present across the mechanical switch contacts prior to turning
on a pump.
When a pump is suddenly turned on under
these conditions, large transient current surges could be expected as the motor
begins to rotate. These transient surges often cause heating of the electrical
contacts which, over time, effectively reduce the lifetime of the switch. This
condition is further amplified when a mechanical switch attempts to open and
turn off the pump.
When a mechanical switch suddenly opens
an inductive motor load, the time rate of change of the current flow can be very
large. This value, multiplied by the motor’s internal inductance, induces a
large voltage transient across the mechanical switch contacts. This transient
often causes arcing of the contacts which over time, can cause the switch to
wear and ultimately fail. It is well known in the sump pump industry that the
cause of most pumping failures occurs when the pump switch fails.
The embodiments of the ION Switch
effectively eliminate the problem of switching transients and contact arcing by
incorporating both a solid-state switching device in parallel with an
electrical relay. When a pump is called for, the turn-on cycle begins by
enabling the solid-state device. The solid-state device in Metropolitan’s
design is to switch on a load under low voltage conditions. By engaging the
electrical relay from a low-voltage potential, both radiated and conducted
electrical noise have been dramatically reduced.
The Ion Digital Level Control is
universal and can be used in almost any pumping application dependent on level
control as well as effluent sump and sewage. To customize operation, the Ion
Digital Level Control has standard differential heights of 6 inches for
standard sump applications and 10 inches for sewage applications, and is
inverter rated for use with most battery back-up systems. The Ion can be
programmed for custom applications as well.
“We feel the Ion Digital Level
Controller will transform the pump industry much the way battery back-up
systems did in the 1980s, because we figured the way to eliminate the moving
parts associated with most switch failures,” Kochan, Jr. says.
“As wholesalers and plumbers realize
there is a product available that can eliminate the problems associated with
mechanical switches, it will only be a matter of time until mechanical switches
are replaced entirely.”
For further information about the Ion
Digital Level Controller visit www.IonNation.us.
Joseph Sanchez
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