The VibraRod™ vibrating
rod sensor provides reliable point level sensing in a wide
variety of applications within powder and bulk solids markets.
The vibrating probe principle utilized by the VibraRod overcomes
typical application difficulties associated with changes
in material, electrical dielectric constant, temperature
or humidity while providing reliable solid state electronic
circuitry that requires no calibration. The VibraRod has
the ability to detect a wide range of material densities.
The VibraRod line
of vibrating rod point level sensors is offered in standard
length, cable extension or pipe extension versions. The standard
length version extends into your vessel approximately 9 inches
(235 mm). The pipe extended version can be used to extend
the measuring rod up to 120 inches (3 m) and the cable extended
unit can be used to extend the probe up to about 65 feet
(20 m). Each version can be provided with either a plastic
or aluminum housing. VibraRod units
are provided with local indication using a bi-color LED and
a traditional relay output.
The VibraRod™ line
of point level sensors is a mechanical resonance system that
is excited and kept in resonance by the sensor's electronic
circuitry. Two piezoelectric crystals are mounted on the
internal portion of the probe’s base. An electrical
signal is applied to one crystal at the frequency corresponding
to the probe’s self-resonance. This electrical excitation
causes physical deformation of the crystal which in-turn
creates probe vibration. When no material is present around
the VibraRod's
probe, the vibration of the probe is received by the second
crystal. This causes physical deformation of the second crystal
which generates a voltage analyzed by the electronic circuitry.
With material present and surrounding the probe, the vibration
is dampened so that the second crystal is not able to generate
as high a voltage as when no material is present. The electronic
circuitry senses this change and the relay output changes
accordingly.
Applications
The VibraRod™ level
sensor provides reliable point level sensing in a wide variety
of applications for most bulk solid materials. The single-prong
vibrating rod principle requires no calibration, is easily
setup and eliminates the application problems associated
with build-up and clogging between tines on a typical "tuning
fork" device. The VibraRod is
ideal for bulk solids ranging from 3.12 lbs/ft³ (0.05 kg/dm³ )
with a maximum particle size of about 3/8 inches (10 mm)
and is even self-cleaning via vibration in many applications.
Typical Applications include, but
are not limited to:
Food Products
Chemicals
Clay
Sawdust
Fly Ash
Grain
Carbon
Black
Plastics
Lime
Sand
Cement
Feed
Pellets
Rice
Flour
Tobacco
Features
SINGLE-PRONG
PROBE DESIGN
The VibraRod™ provides
a probe design superior to "tuning fork" devices and
eliminates problems associated with build-up between tines of
"tuning fork" devices. In addition, theVibraRod's
vibration acts as a self-cleaning effect for most materials,
which can further eliminate problems. The reinforced 316 stainless
steel rod provides a high
level of corrosion resistance suitable for virtually any application.
IMMUNE
TO CHANGES
The unique design of the VibraRod level
sensor makes it immune to changes in many different application
variables including:
Vessel
contents
Material
composition
Density
of material
Dielectric
constant
Particle
size
Moisture
content
Pressure and Humidity
Temperature
NO
CALIBRATION REQUIRED
The VibraRod level
sensor is very easy to use. Unlike RF Capacitance type sensors,
no calibration is required. Simple switch adjustments for time
delay, fail-safe and sensitivity are all that is required to
setup and use the VibraRod point
level sensor.
SELECTABLE
FAIL-SAFE MODE
The VibraRod is
selectable for high or low fail-safe mode. This allows the
user to set the output "state" upon alarm activation
and power failure.
LOCAL
INDICATION
Each VibraRod level
sensor includes a bi-color LED to indicate power and material
absence/presence (Ordinary location sensors only).
UNIVERSAL
POWER SUPPLY
All VibraRod level
sensors can be provided in either a high or low voltage design.
The high voltage design can be used with 85-265VAC and 120-375VDC.
The low voltage design requires either 16-40VAC or 19-55VDC.
This added flexibility allows two power supply ranges to cover
all possible requirements.
CHOICE
OF HOUSING MATERIALS
A choice of either plastic or aluminum is offered.
CHOICE
OF PROBE CONFIGURATIONS
Flexibility for virtually any bulk solids point level application
(top or side mounted) is enhanced with a choice of three probe
configurations: Standard, Cable Extension and Pipe Extension.
HAZARDOUS
LOCATION VERSION
The Standard, Pipe Extended and Cable Extended configurations
of the VibraRod level
sensor (aluminum housing only) can be provided with ATEX hazardous
area certification. This allows the VibraRod to
be used in areas where hazardous explosive dust is present.
Available Configurations
STANDARD
PROBE
The standard probe is approximately 9-1/4 inches (235 mm) in
length and is suitable for both top and side mount applications.
It mounts to the vessel with a 1-1/2" NPT or BSP connection.
PIPE
EXTENSION PROBE
For high and low level applications that extend beyond the
length of the standard probe, the VibraRod™ can
be provided with a pipe extension probe. This configuration
is intended for top mount applications only. The extension
is constructed of 1" stainless steel pipe, which provides
structural strength and affords a means to secure the assembly
to the vessel. The pipe extension probe is available in lengths
up to 10 feet (3 m) in length. The unit mounts to the vessel
with a 1-1/2" NPT or BSP connection.
CABLE
EXTENSION PROBE
The cable extension probe configuration extends the detection
length beyond the standard and pipe extension probes. This
version of the VibraRod level
sensor is for use in top mount applications only and can be
used for both high and low level applications. A polyethylene
(PE) coated steel reinforced cable is used for the extension
and is available in lengths up to 65 feet (20 m). The unit
mounts to the vessel with a 1-1/2" NPT or BSP connection.
Specifications
Power
Requirements:
High
Voltage:
85-265VAC(50/60Hz)
or 120-375VDC
Low
Voltage:
16-40VAC(50/60Hz)
or 19-55VDC
Power
Consumption:
High
Voltage:
≥ 2.5VA
(AC); 1.2W (DC)
Low
Voltage:
≥ 2.5VA
(AC); 1.3W (DC)
*Process
Temperature:
Std.
Probe:
-22° to
230° F (-30° to 110° C)
Pipe
Ext. Probe:
-22° to
230° F (-30° to 110° C)
Cable
Ext Probe:
-13° to
194° F (-25° to 90° C)
Ambient
Temp:
-22° to
140° F (-30° to 60° C) all units
Output
Relay:
SPDT
isolated; 8A @ 250VAC max
Sensitivity:
3.12lbs/ft³
(0.05kg/dm³ ) min density (max particle size=3/8in(10mm);
Switch Selectable: High (>6.24lbs/ft³ or 0.1kg/dm³ )
or Low (≤ 6.24lbs/ft³ or 0.1kg/dm³ )
Time
Delay:
Switch
Selectable:
On-Delay (when immersed):
<1.8 sec OR 5 ± 1.5
sec;
Off-Delay (when free of material):
<2 sec OR 5 ± 1.5
sec
Bi-color
LED; Red indicates de-energized relay and output "on";
Green indicates energized relay and output "off";
No LED illuminated indicates improper supply voltage
or damaged circuitry
Probe
Material:
Std.
Probe:
316Ti
SS (DIN 1.4571)
Pipe
Ext. Probe:
Probe is 316Ti
SS (DIN 1.4571); 1" pipe is 316 or 316Ti
(Europe Only; DIN 1.4571)
Cable
Ext. Probe:
Probe is 316Ti
SS (DIN 1.4571) Polyethylene coated, steel reinforced
cable; max 65ft (20m)
CE Mark
ATEX(EX) II 1/2 D IP 665 T (T rating
dependent on model, consult factory) (zone 20/21)
* Influenced
by the ambient temperature. Refer to Installation & Operation
manual for details.
Warranty
Monitor
Technologies LLC warrants each VibraRod™ it
manufactures to be free from defects in material and workmanship
under normal use and service for two (2) years from the date
of purchase. The purchaser must notify Monitor of any defects
within the warranty period, return the product intact, and
prepay transportation charges. The obligation of Monitor
Technologies LLC under this warranty is limited to repair
or replacement at its factory. This warranty does not apply
to any product which is repaired or altered outside of Monitor
Technologies' factory, or which has been subject to misuse,
negligence, accident, incorrect wiring by others, or improper
installation. Monitor Technologies LLC reserves the right
to change the design and/or specifications without prior
notice.
533A.2.0406
SiloPatrol® SE Measuring coal
powder levels when nothing else will work ….
Coal-fired power plants are commonplace around the
world. In order for these power generating stations to create
huge amounts of electricity the turbines need to be feed with steam
and the steam created by boilers that are fired by … yep,
coal. But coal as it comes from the mining operations is not
what is fed to the burners. First it is ground or pulverized
into powder. It is not unusual for the coal powder to be stored
in silos awaiting the demand for it to be fed to the burners. The
inventory of coal powder in these silos needs to be monitored to
allow for efficient operation of the power plant.
So, how do we monitor the inventory of coal powder in a silo? Not
easily. In one typical application the power plant personnel
found that the only technology that would work reliably is the modern
smart weight & cable system from Monitor Technologies LLC, the
SiloPatrol® SE.
Anhui
Tongling power plant in Anhui province in China had tried almost
ever technology possible to get a reliable level measurement in their
5 coal powder silos. Radar, ultrasonic and others were tried,
but none worked reliably. It wasn’t until Beijing Conasen
walked in and proposed that the Tongling plant use the SiloPatrol
SE smart cable-based inventory monitoring system that the power plant
personnel found a reliable solution.
Mr. William Yuan, sales manager for Beijing Conasen indicates that
the power plant tried many major brands of ultrasonic, radar, and
other technologies but that due to good relations with the Tongling
plant personnel he was able to sell three SiloPatrol SE model SMU
sensors and an HMI operator interface to them. The units were
installed by plant personnel. Because of the heavy amount of
coal dust in the silos an air purge using dry compressed air was
used. The SiloPatrol sensor incorporates the patent-pending
use of Hall-effect sensor technology, a split-compartment enclosure,
microcontroller, redundant optics and many other valuable features
and technology to ensure reliable measurement even in challenging
dust applications like coal powder.
The SiloPatrol SE system has been working reliably and the plant
has since purchased two additional sensors and connected them into
the same HMI operator interface. This same sensor technology
is working reliably at other coal-fired power stations in China as
well.
For more information on the SiloPatrol SE click
here or contact Monitor Technologies LLC at 800-766-6486 in the
USA and 630-365-9403 worldwide.
CLICK
HERE TO SEND PAGE TO A COLLEAGUE