Wednesday, December 17, 2014

Ohms Law and Wattages for Electric Heaters and Elements

Flow Factor and Ohms Law

Electric Heaters and heating elements become hot due to a voltage being pushed through a wire.  The resistance in the wire measured in Ohms creates the heat.  The more resistance the hotter the wire gets. The more voltage pushed through the wire, the hotter the wire gets. Simply the smaller the wire (or the longer the wire run) the more resistance it gives to the voltage passing through.

So as voltage increases the wattage will increase four fold.  As the voltage decreases the wattage will decrease by a factor of 4 as well.  The below table shows the percentage of drop or gain with different applied voltages to a heating element.

Rated at 480 volts the expected wattage % is
575 applied  144%
480 applied  100% (Rated Watttage)
440 applied   84%
240 applied   25%
120 applied    6%

Rated at 277 volts the expected wattage % is
277 applied 100% (rated Wattage)
240 applied  75%
230 applied  69%
208 applied  56%
120 applied  19%

Rated at 240 volts the expected wattage % is
277 applied 133%
240 applied 100% (rated wattage)
230 applied  92%
208 applied  75%
120 applied  25%  (1/4 wattage)

Rated at 120 volts the expected wattage % is
240 Applied  400%  (4 times wattage - Dangerous) 
208 Applied  300%  (3 times wattage - Dangerous)
120 Applied  100%  (rated Wattage)
110 Applied   84%

This is all based on Ohm's Law or I=E/R

Simple Ohms Law equations are:

Watts = VOLTS x AMPS
Volts = AMPS x OHMS

A Conductor Wire's resistance is constant based on wire size and length.
A heater's watt rating is based on the wire used in the heating element and the voltage applied.
To get a 15 kilowatt rated heater run at 480 volts; a wire with a resistance of 15.4 Ohms is used.
(If there are three elements in the heater, then each is rated at 5 kw and the resistance of the wire would be 46.)

Knowing amps is very important for large immersion heater loads to size contractors, SCR's, Fusing and Thermostats.

Contact Flow Factor for all sizing help with heaters and accessories.


Tuesday, August 26, 2014

Penberthy Jet Pumps

Penberthy jet pumps from Flow Factor

Penberthy Jet Pump (eductor)

56877-090   GL series STEEL

56877-010   GL series IRON

56877-030   GL Series STAINLESS

56875-010   GL series IRON

56876-000   GH series BRONZE

56844-000    LL series  BRONZE

56870-000   GH series  BRONZE

56849-020   LH series PVC

56847-020   LH series PVC

56873-010   GL series IRON

56877-000   GL series BRONZE  1-1/2 inch

56874-010   GH series IRON

56880-000   GH series BRONZE

56876-030   GH series  STAINLESS

56864-030  GH series in Stainless

Penberthy eductors cane used for mixing, heating and blending of gases, liquids and some solids.


Thursday, July 31, 2014

Parker Skinner Fluid Control Division

Parker's FCD ( Fluid Control Division ) manufacturers of the Skinner and Gold Ring lines of solenoid valves and the Sinclair Collins line of process control valves, now offers a six-port Marine Selector Valve for electric remote tank selection in boats with multiple diesel fuel tanks.

Being a solutions provider means helping our customers achieve higher levels of success by engineering the best systems for their requirements. It means looking at the customer applications from many angles to find new ways to create value.

Parker 2 way valves for on off control of fluids (water, oil, air, gasses). Powered by a solenoid coil.

Parker 3 way valves for operating cylinders, control valves and diverting flows.

Parker 4 way valves for operating double acting cylinders and other accuators.

Parker Angle Body valves for slurries and other hard to control fluids.  2 and 3 way available and analog control.

Parker Sinclair Collins Control valves for proportional valve control.

Please use our Solenoid Valve Parts form for quotes and questions.

Call toll free for quotes and questions.  866-360-9830

Saturday, June 21, 2014

Stiebel Eltron Tempra Tankless Water Heaters

Tankless Technology by the Electric Tankless Leader, Stiebel-Eltron and Flow Factor

The Tempra® series has been redesigned completely inside and out - upgraded heavy-duty electronics, a simple single flow sensor design, a hinged cover for easy access, and Tempra Advanced Flow Control for the Tempra® Plus.

The Tempra® continually heats water instantaneously as you require it - and only when you require it. The Tempra® unit completely replaces a conventional tank heater with no disruption to your comfort and hot water needs.

he Tempra® Plus is the most technologically advanced tankless water heater available on the market today.

Tempra Advanced Flow Control is exclusive to the Tempra® Plus and ensures a constant temperature output no matter how great the hot water demand is.

Tempra Advanced Flow Control technology works by automatically adjusting the flow of water to eliminate unpleasant temperature fluctuation.

What that means to you is a consistently satisfying experience every time, all the time!

Electric tank type water heaters are subject to stand-by losses which amount to 15 - 20% of the kWH used. In addition, water in a tank has to be heated hotter than necessary to account for these stand-by losses.

Changing to a tankless system like the Tempra® eliminates these problems and results in typical savings of at least 15 - 20% on the hot water portion of your electric bill.

Set the knob on the front cover and enjoy water temperatures between 86°F (30°C) and 140°F (60°C). Change the desired temperature at anytime. Advanced microprocessor technology ensures that the water temperature never deviates from the set point.

The Tempra® has several advantages over a gas-type tankless water heater. Compared to many similar gas tankless models the Tempra® is less expensive to purchase. Installation is also much simpler and cheaper since it is not necessary to vent a Tempra® to the outside.

The venting that a gas unit requires causes anywhere from a 10 - 20% efficiency reduction from heat escaping out the exhaust pipe. Furthermore, for every cubic foot of gas burned, roughly two cubic feet of air have to be mixed in to create ideal combustion. In a cold climate, this hurts efficiency further.

When a gas unit fires it draws in air around it, heats the water, and then expels warm exhaust outside. Since no house is airtight, this suction action causes a drafting condition where cold air from the outside seeps back in through door cracks and other parts of the house that may not be airtight.

By nature of the design, the Tempra® is nearly 100% efficient; converting 100% of the electrical energy it consumes into heat. All that heat is then transferred to the water - none is lost to the outdoors.

The Tempra® is a tankless water heater system, and is thereby not subject to seismic code. There is no need for preventative construction, as required when using a tank type water heater.

The Tempra® has several temperature and flow sensors which feed their readings into the unit’s proprietary microprocessor control. Heating elements are engaged in stages, achieving the temperature you desire. The Tempra® continually monitors the water temperature it produces.


Friday, June 20, 2014

Bosch / Ariston S series Mini-Tanks

Ariston Mini-Tanks updated to S series - Flow Factor

The new Ariston GL6S Plus electric mini-tank water heaters have just arrived. This water heater is the direct replacement for the recently obsoleted Ariston GL6+ (GL6PLUS).

The main difference between the older GL6+ and the new GL6+S is that the GL6+ came with a power cord that plugged directly into a 120V wall socket while the new GL6+S does not come with a power cord. The GL6+S must be hardwired at the time of installation.

Globaltowne does carry a 6' cord for the Ariston GL6+S

Here are the features of the new GL6+S: 
  • 6-year warranty on tank
  • Glass-lined tank for longer life
  • Mounts on wall or floor
  • Temperature/pressure relief valve included
  • Must be hard-wired to 120V
  • Dimensions: 17.5" x 17.5" x 14 1/2"
  • Recovery at 90 Deg F Rise: 7 GPH
  • 12.5 AMPS and 1500W Heating Capacity
  • Temperature Range: 65 Deg F to 145 Deg F
  • Meets ASHRAE 90.1 Standard
  • Relief Valve = Installed
  • Power cord not included
The new Ariston GL6+S model has many new improvements since it has been upgraded. The mini tank has a new temperature adjustment knob on the front of the unit to raise and lower the temperature from 65 Deg F to 145 Deg F. On the older model you would have to remove the blue oval cover to access the temperature knob.

The Ariston GL6+S model has a new improved thermostat that features a new sensing probe that is attached to the thermostat and inserts into the cavity of the new element so the heater can adjust temperatures quicker and maintain a more consistent heat.

Designed by the world's leading point-of-use water heater manufacturer, the New Ariston GLS series combines Italian design and state of the art features including glass-lined tanks, a 6-year warranty and highest recovery time. 

Installing an Ariston electric mini-tank water heater under the sink puts hot water right where you need it - at the point of use. Lightweight and compact and also the Ariston mini tank heaters are great for those long hot water runs from your tank heater or tankless heater and will shorten the wait time for hot water.

The New Ariston GL2.5S mini-tank electric water heater stores 2.5 gallons of hot water. 

The New Ariston GL4S mini-tank electric water heater stores 4 gallons of hot water. 

Please note: The New Ariston GL2.5S is not the direct replacement for the Ariston GL2.5 as the Ariston Gl2.5S is 10 3/4" in depth and the older Ariston GL2.5 was 10 1/4" deep.  The new Ariston GL4S is not the direct replacement for the Ariston GL4 as the GL4S is 13 1/2" in depth and the older Gl4 was 12 1/4" deep.  The replacement parts for the new Ariston GL2.5S and the GL4S will not work for the older GL2.5 and GL4 mini tank heaters.

  • 6-year warranty on tank 
  • Glass-lined tank for longer life  
  • Mounts on wall or floor 
  • Temperature/pressure relief valve included  
  • Plugs into standard 120 volt outlet
  • Dimensions: GL2.5S-13 3/4" x 13 3/4" x 10 3/4", GL4S-13 3/4" x 13 3/4" x 13 1/2"
  • Recovery at 90 Deg F Rise: 7 GPH 
  • 12.5 AMPS and 1500W Heating Capacity 
  • Temperature Range: 65 Deg F to 145 Deg F  
  • Meets ASHRAE 90.1 Standard
  • Relief Valve = Installed
The new Ariston GL2.5S & GL4S models have many new improvements since they have been upgraded.  The mini tanks have a new temperature adjustment knob on the front of the unit to raise and lower the temperature from 65 Deg F to 145 Deg F.  On the older models you would have to remove the blue oval cover to access the temperature control knob.

The Ariston GL2.5S & GL4S models have a new improved thermostat that features a new sensing probe that is attached to the thermostat and inserts into the cavity of the new element so the heater can adjust temperatures quicker and maintain a more consistent heat.


Saturday, May 31, 2014

Robertshaw Capacitance Level Information

Flow Factor Robertshaw Capacitance Level Control

For a quote or information request, please click HERE.

Capacitance instrumentation is an example of measurement where the
process variable (level for example) causes a capacitance signal to be
generated that the instrument acts upon to provide an output or signal
proportional to the change in the process variable.

Electrical "capacitance" is the property (or measure) of two conductors (or plates), electrically insulated from each other, to store energy when a
difference of electrical potential exists between them. Under these
conditions, an electrostatic field exists between the conductors and the
amount of stored energy is a function of the area, spacing, electrical
potential and the material between the conductors.

The unit of measure of capacitance is the "Farad", however the "pico-farad" is used in capacitance instrumentation. This is abbreviated "P? and is equal to 1 x 10 to the -12 Farads. Most capacitance instrument manufacturers specify the operating range, sensitivity, adjustments, etc. of the instrument in pico-farads.

The amount of "capacitance" in any given capacitor is determined by the area, spacing of the plates and the material between the plates.  This can be
seen in the equation for the capacitance of a simple parallel plate capacitor as shown

Capacitance = 0.225 K x A/D
Where :  K = Dielectric constant of material between the plates
               A = Area of the plates
               D = Distance between the plates

The equation indicates that the capacitance is directly proportional to the dielectric constant, directly proportional to the area of the plates, and inversely proportional to the spacing or distance between the plates.
Dielectric constant (K) is a dimensional number to relate the amount of capacitance generated when anything other than air is used as the material between the plates. For example, if some material was inserted in the "air" capacitor that caused the capacitance to double, the material would have a dielectric constant of 2 or twice that of air. The dielectric constant number, then relates capacitance generated to that of air.
All materials have a dielectric constant value. For practical purposes, all gases (including air) have a dielectric constant equal to (1). If then, the air in an air-filled capacitor was displaced by a liquid, the capacitance increase of the capacitor would be directly proportional to the change in dielectric constant (K) between the liquid and air.
This is the fundamental concept upon which all capacitance instrumentation is based.
Generation of the Capacitance Signal
For most applications of capacitance instruments, the method used to
generate a capacitance signal consists of placing a rod type electrode
(probe) in contact with, or in close proximity, to the process material.
If, for example, it were a level application, the changing level of the
material within the vessel would create a change in the measured
capacitance at the probe. The magnitude of the capacitance change is
determined by the geometry of the installation, probe type, vessel and the product being measured.

When measuring a non-con0uctive material, the change in level is
indicated by a change in the dielectric constant (K) of the material between the plates of the capacitor. As the level rises, the air or gas normally surrounding the probe is displaced by material having a higher dielectric constant. The grounded metal vessel acts as the ground plate, and the mass of material between the plates is the variable. As the level changes, the capacitance varies because the dielectric between the electrodes has changed.

When measuring a conductive rather than the vessel wall acts as the ground plate. In this case, the area (A) in material, the measured material itself, contact increases as the level increases, resulting in a change in the capacitance of the system. Insulated probes are used in this type of application to separate the conductive material from the probe. The thickness of the insulation is the distance (D) between the plates.

In proximity (non-contacting) type sensors, the distance (D) between the plates decreases as the level rises. If the material is conductive, the surface of the material forms one plate of the capacitor. If the material is nonconductive, two capacitors are in series - one through the air, and one through the measured material. For either conductive or non-conductive material, the capacitance changes as the material approaches the probe, because the distance or dielectric between the electrodes has changed.

Successful application of any capacitance instrument depends upon an
adequate change being generated by the process. The word "change' is
emphasized since all capacitance measurement systems start with an
initial or "terminal" capacitance value and increase to some final value as a function of the process variable. The change in the capacitance is denoted delta C. Each instrument has a specified minimum capacitance change upon which it will operate, therefore, an estimation of the generated capacitance signal must be made to ensure satisfactory instrument performance.


1. Continuous
a. Overall with indication and/or output
b. Interface with indication and /or output
c. Proxlmity with indication and/or output
d. a, b, or c with relay/alarm outputs

Note: Continuous interface (immiscible liquids only) measurement can only be accomplished when one product is conductive and the other is nonconductive (oil/water, toluene/water, etc.) A vertical mounted probe is used and, in most cases there can only be two variables involved and tank should always be full with no air. Exceptions are where the third variable is very close in dielectric constant to the non-conductive product or where you can use a sheath to eliminate the error introduced by the third variable. The sheath will extend through the upper third variable (air for instance) and below the lowest point the overall liquid levels will ever reach. In all interface measurements you will be measuring the conductive product. Interface applications should be considered by individual application. Emulsion layers are also a problem.

2. On/Off Point Level (s) with or without Differential

a. Single or multiple point
b. Interface (no differential)
c. Proximity

Note: On/Off interface measurement uses a horizontal mounted probe and the product being measured must differ in dielectric/conductivity than the other products in the tank. Emulsion layers are a problem.

Principle of Short Stop Operation

In point level control, a conductive coating on a horizontally mounted
probe often causes false relay trips when the material level has risen
above, and then falls below, the detection point. The current passes
through this coating to the vessel wall, completing the circuit. The point level switch continues to indicate - now incorrectly - that the level is above the alarm point.
The Short-Stop feature ignores the effect of conductive material buildup. A second element added to the probe is electronically maintained (or driven) at the same voltage and frequency as the measuring tip. This means that no current can flow through the coating to the vessel wall. When the actual level reaches the bare tip, current can flow to the tank wall only through the material being detected. In this way, the driven shield technology eliminates erroneous signals due to current passing through the material coating the probe.


Probe Installation

Horizontally mounted rod type probes must be installed in the vessel at the desired point of level detection. This type of installation provides the closest control (smallest deadband) in that a small change at or near the probe will produce a large capacitance change. On applications involving viscous liquids or materials that have a tendency to "cling" or "build-up" it is recommended that the probe be mounted on a slight downward angle to permit draining of the material from the probe. The instrument actuation point should be set so that the high level point is always below the gland" If the horizontally mounted probe is to be installed in a recess or nozzle, the use of a "sheathed" probe is recommended. This type of probe has an inactive (sheathed) portion near the mounting gland so as to eliminate false operation if material collects or packs within the recess or nozzle.


Vertically mounted probes can be mounted in either the top or bottom of the vessel with the probe midpoint corresponding to the approximate desired level detection point for On-Off instruments. This allows a variation in the level detection point up and down the length of the probe by means of the instrument zero adjustment.
Proportional instruments for level measurement require a probe longer
than the intended measurement span. For probe lengths exceeding 10 feet, a flexible probe is recommended, primarily for shipping considerations. Long flexible cable probes are offered with optional lower end fittings for weights or tie-downs. If top mounted probes are mounted through a nozzle and process has high vapor content or subject to condensate forming in the nozzle, then a sheath should be considered.

Continuous Level Measurement in Liquid Products

The Continuous measurement of level in a tank containing liquid can be
made by a number of methods. One of the simpler and more reliable
methods is by capacitance techniques. The liquids and slurries which can
be measured by capacitance covers a wide range of products, including
aqueous solutions, hydrocarbons, acids, alkalies and slurries of rock
products, paper products, etc. The "self-cleaning" characteristic of Teflon
covered probes, as well as their excellent chemical resistance, make the
capacitance method almost universal in its application to liquid level
measurement. An advantage of capacitance techniques in liquid level
measurement is that the specific gravity of a product is not a factor except in terms of viscosity (ability of the product to freely flow or drain from the probe.

Typical Applications

The probe can be either the rigid or flexible type. The rigid types are
usually limited to 10 feet in length, while flexible types can be made up to 100 feet or more. Figure 1 shows graphically the range of dielectric constants with various products. The low dielectric materials are liquefied gages such as LOX and nitrogen - typically these products range from 1.05 for helium to 1.5 for oxygen. Hydrocarbons will range from 2.0 to 6.0 with the heavier oils being the higher of the group. Next is the family of alcohols and ketones which range from 12 to 35. The very high dielectrics are aqueous solutions and many of the common acids or alkalies. These are in the range of 75 to 90.

Probe Selection and Location

Very low dielectric materials will produce low capacitance changes when compared between air (vessel empty) and the vessel full capacitance. The
liquefied gases have such low dielectric constants that the total capacitance
change with standard probes is insufficient to produce full span outputs.
Therefore, the probe or installation must be modified to produce a larger
capacitance change. In low dielectric liquids, that are free of solids, this is
most easily accomplished by using a concentric probe. This probe will
produce several times more change per foot of measured product on low
dielectric materials than the standard probes.
The minimum range (span) of the Level-Tel instruments is 10 Pf for full
output. It is therefore required that the measured material produce a
capacitance change of at least 10 Pl but a much higher change is
preferred. The maximum range (span) of the Level-Tel varies with the
particular instrument, but ranges from 1OO0 Pf to 6000 Pf and represents
many feet of material when the dielectric is low.
The higher dielectric materials, such as alcohols, aqueous solutions and
acids and alkalies, produce large capacitance changes with only a few feet
of measured material. Therefore, these products are measured most
satisfactorily with standard probes, either rigid or flexible. The probes are
mounted so that they are located in a vertical position within the vessel as
indicated in figure 2. The probe should be located so that the product does
not flow on the probe during filling. In applications where considerable
turbulence of the liquid occurs, it is suggested that a 'stilling well" be
Continuous Level Measurement in Granular Products

Continuous level measurement of granular products is one of the more
difficult measurements because of the physical characterisitics of the
materials. Capacitance techniques offer one of the more accurate, reliable
and simplest methods of continuous level measurement of granular or
powdered materials in silos, hoppers and bins.

Typical Applications

A probe, either rigid or flexible, is installed within the vessel in such a
manner that the measured material will surround the probe. The
capacitance, as sensed by the probe, will vary directly with the level
(height) of the material in the vessel. Figure 3 shows a typical graph of
dielectric constant versus capacitance generated for some common low
dielectric products. Remember that the net change is the difference
between air and the product being measured. For example, wheat flour has
a dielectric constant of approximately 3.0. With a flexible probe mounted
concentrically in a 24" vessel, wheat flour will generate approximately 9 Pf
per foot on the probe. With air surrounding the probe (vessel empty), the
capacitance is approximately 3 .5 Pf/ft Therefore, the wheat flour will
produce a net capacitance change of 5.5Pf/ft Avessel of 15 feet in height,
having a "full" design point of 12 feet, would produce a new capacitance
change of 56 Pf ( 12' x 5.5 Pf/ft.)

The Level-Tel transmitters have a measuring range (span) from 10 Pf
minimum to several thousand Pf maximum. The minimum full span of
level for wheat flour is approximately 1,8 feet (10 Pf divided by 5.5 Pf/ft),
while the maximum span could be well over 100 feet. Notice that the span
can vary from a few feet to many feet dependent upon the material being

A general rule of thumb is that low density products, those which weight
only a few pounds per cubic foot, generally have low dielectric constants
while high density materials (in the same family) will have higher
dielectric constants. The change in dielectric constant with density for a
given family of products results from the particle size and shape, which
affects the amount of air entrapment in the material. The greater the air
entrapment, the lower the dielectric constant. Mineral oxides generally
have higher dielectric constants than flours, cereals, etc. because they have
higher densities.

Probe Selection and Location
The probe must be mounted to hang vertically in the vessel so that it may
continuously sense the rise or fall of the material. The probe, if the rigid
type, is entered and supported at the top by its gland assembly. Typically,
rigid probes are limited to 10 feet in length. For vessels requiring longer
probes, the flexible type is used and is either mounted by means of its
gland or suspended by means of insulators, which are supported by
mechanical means within the vessel. Typically the probe is mounted
midway between the center and sidewall of the vessel, as shown in figure
4. ln this way, it measures the average volume of material in the vessel
even when the product has a large angle of repose. Flexible probes are not
fastened or tethered to the bottom of the vessel in most granular


Proximity (Non-Contact) Measurements

On many level control applications, it is impractical to use immersed
probes as the sensing element. Products which have adhesive
characteristics can often be controlled within close limits through the use
of a non-contacting probe which is placed above the product surface. Many
products, having a tendency to congeal and harden when exposed to air or
changes in temperature, can make use of this technique. Other applications
include those where thickness of product must be maintained within tight
specified limits. All of these applications can make use of "proximity."

Typical Application Data

There are 2 major areas which must be considered when using proximity :
1. The size of the probe (or flat Plate)
2. The dielectric of the material being sensed

The first consideration is the size of the probe which can be installed in the
vessel whose level is to be controlled. The area of the probe must
correspond to the material level control requirements. Reference figure 5
shows the relationship between the area of the sensing probe and the
capacitance change which will result as a conductive material changes its
level. Consider a typical application where it is desired to control the level
of a conductive adhesive material : the material is in a heated vat and is
used as a coating product for paper, fabrics, etc. It is desired to control the
level to + or - 0.25" and the maximum free space available in the vat will
permit a probe approximately 6 x 16 inches. This probe should be spaced
from the sides of the vat and any rolls or mechanisms by at least one inch.
The active area of the plate will be 6 x 16 : 96 square inches. Referring to
figure 5, it will be observed that for a plate of 100 sq. in., the level will
move from a minimum distance of 1 inch to a maximum of 2.5 inches to
produce a capacitance change of 13.5 Pf, (9 Pf to 22.5 Pf = 13.5 ).

The second curve, which shows the capacitance generated for a 25A sq, in.
plate, would produce a change in capacitance of 17 Pf for a level change of
approximately two inches. To produce a change of 10 Pf would require a
total level change of approximatety 3 / 1 inch. Notice that the portion of the
curve considered has been through the center of the curve. This should
always be done for any particular plate area since it is in this area that the
capacitance change is most nearly linear to level change. Other curves are
easily calculated from the formula and it is suggested that for any
particular application, the curve be plotted for the probe area in order to
determine the desired spacing capacitance generated.

The second consideration mentioned earlier involved the dielectric
constant of the material. When the material is a conductive fluid or
product, such as aqueous solutions, acids, alkalies, etc. , the curves may be
used directly. When the materials involved have low dielectric constants, a
factor must be applied. For example, if the material is a hydrocarbon
having a dielectric of 3.0 to 4.0, the capacitance change will be
approximately L/6 of the change which would have occurred from a
conductive or high dielectric material. Thus, it will require a much larger
change in level to produce a given capacitance change, BUT THE MAXIMUM