"TRUE" FAIL-SAFE ROTARY PADDLE BIN MONITOR

BULLETIN 253

?Imagine a bin level sensor that is more than just an indicator of the presence or absence of material. Picture technology that allows inteligent devices to indicate when something is wrong. Dream that a level sensor provides real-time information when the quality of the sensor function no longer allows it to operate as you expect. That is a “self-validating” bin level indicator. Now you can wake up, your dream has arrived. Costly overfilling and outages due to sensor failure can now be avoided!

The SafePoint® self-validating bin monitor is the state-of-the-art in rotary paddle technology. Going beyond traditional fail-safe sensor technology that only protects against power failure, the SafePoint bin monitor is the most reliable, rotary paddle point level control sensor available.

The SafePoint bin monitor provides the ultimate in performance wherever critical continuous operation must be ensured. Detection of both material presence and its own operational status is performed on a continuous basis.

The SafePoint level sensor monitors its electrical and mechanical operating condition. This, in conjunction with separate outputs for material sense and unit status (fault conditions) make the SafePoint a self-validating device.

Principle of Operation

?While the SafePoint bin monitor is an evolution in rotary paddle technology, it continues to use tried-and-true operating techniques. Unlike many other available units, the SafePoint incorporates a feature that automatically shuts off its motor when the paddle is in a stalled condition. This extends the life of the unit and minimizes maintenance.

The operation of the SafePoint® rotary paddle bin monitor uses patented technology to detect material presence and operational status of the unit. The unit is installed through the wall of the vessel so that the paddle protrudes inside the vessel. A small electric motor drives the paddle, which rotates freely in the absence of material.

The rotation of the unit’s shaft is continuously monitored by detection of a magnetized rotating disk. When the paddle is impeded by material, the shaft rotation stops. The motor rotates within the housing and magnetized sections of the motor mounting plate are detected. Use of these patented magnetic sensing techniques eliminates problems that occur with fouling of the optical systems used by other brands.

The built-in microcontroller performs self-validating diagnostics and monitors both shaft and motor mounting plate rotation. This allows the SafePoint to easily distinguish between material presence and any electrical and mechanical failure of the unit. When material presence is detected, the SENSE relay changes state and the drive motor is de-energized to extend motor life. This output is available to control a process function or alarm circuit. When the material level drops, a tension spring returns the drive motor to its original running condition and is reactivated.

A unit failure is detected by sensing a lack of shaft rotation while material presence has not been detected by rotation of the motor mounting plate. In a failure condition the independent FAULT relay will change state. Monitoring the state of both the SENSE and FAULT relays provides the most flexibility for control and monitoring that is beyond being just “fail-safe”.

Applications

The rugged and reliable fail-safe design of the SafePoint® bin monitor makes it the best choice for critical level control applications. The unit is compatible with many granular, pelletized and powder bulk applications. It can be utilized for high level indication of materials over 10 lb/ft³ (160 kg/m³ ) and for low and intermediate level indication for materials over 5 lb/ft³ (80 kg/m³ ). The SafePoint bin level monitor can be installed almost anywhere dry bulk materials are stored including bins, hoppers, silos and tanks.

Features

Available Configurations

Accessories

PADDLE ASSEMBLIES
Monitor offers a variety of interchangeable paddle assemblies to meet the needs of a wide variety of applications. Different material densities, particle sizes and flow characteristics require specific paddles to provide optimum performance. See the paddle selection guide for more detailed application recommendations.

Dimensions are shown in inches with millimeter equivalent in brackets.

1.) Standard Stainless Steel Three Vane Paddle: The most popular of all paddles. For use with average weight materials. P/N 1-4146
2.) Large Stainless Steel Three Vane Paddle: Provides accurate level control for lightweight materials. P/N 1-4141
3.) Insertable* Stainless Steel, Scimitar Single Vane Paddle: Provides low and high level control for light to average weight materials. P/N 1-4193
4.) Insertable*, Stainless Steel Single Vane Paddle: Provides low level control for average weight materials and low to high level control for heavy materials under 1-1/2 inch (40 mm) in diameter. P/N 1-4145
5.) Stainless Steel, Two Vane Paddle: Provides low and high level control for heavy materials under 1-1/2 inch(40 mm) in diameter. P/N 1-4135
6.) Stainless Steel Four Vane Paddle: For use with average to heavy weight materials in low and high level control installations. P/N 1-4156
7.) Stainless Steel Triangular Arc Single Vane Paddle: Provides low and high level control for light to averageweight materials. P/N 1-4144
8.) Ex-Flex Three-Ply 20 inch (508 mm) Belt Vane Paddle: Provides low and high level control for heavy materials over 2 inch (50 mm) in diameter. Top mount only. P/N 1-4137
*Insertable paddles eliminate the need for a mounting plate. 1-4193 is insertable through either a half or full 1-1/4” or 1-1/2” coupling, that is welded to the bin wall. 1-4145 is insertable through a half 1-1/4” or 1-1/2” coupling.
FLEXIBLE COUPLING The flexible coupling works to absorb heavy loads, side loads and loads caused by product surges, thus protecting the internal workings and extending the life of the paddle unit. A flexible coupling should be used with heavy materials and in top mount installations where a solid shaft extension is used. Monitor offers the following coupling option: Spring-Flex: P/N 1-3335

MOUNTING PLATES
Mounting plates allow the paddle units to be mounted from the outside of a vessel to curved or flat surfaces. All mounting plates featured below mount via six bolts.

1.) Half Coupling Mounting Plate: For use in side mount installations. Available in powder coated carbon steel for general purpose applications and stainless steel for use in corrosive environments. Stainless Steel Plate: P/N 1-0112. Carbon Steel Plate: P/N 1-0101 for 1-1/4” NPT connection and P/N 1-0100 for 1-1/2” BSPT connection.

2.) Full Coupling Mounting Plate: For use in top mount installations where a shaft extension and shaft guards are required. Available in powder coated carbon steel for general purpose applications and stainless steel for use in corrosive environments. Stainless Steel Plate: P/N 1-0113. Carbon Steel Plate: P/N 1-0102 for 1-1/4" NPT connection and P/N 1-0115 for 1-1/2" BSPT connection.

3.) K-Flange Aluminum Mounting Plate: For flat surfaces or thin walled vessels where extra strength is required. Ideal for semi-corrosive environments, including outdoors. P/N 1-3316.

SHAFT GUARDS
Shaft guards are recommended for use with solid shaft extensions to limit the movement caused by side loading that would otherwise damage the working components of the paddle unit. Shaft guards should be the same length as the extension and should always be used when the extension meets or exceeds 18 inches (460 mm) in length.

Specifications

*Influenced by mounting, material thermal conductivity and ambient temp.

Warranty

Monitor Technologies LLC warrants each SafePoint® rotary paddle bin indicator it manufactures to be free from defects in material and workmanship under normal use and service within two (2) years from the date of purchase. The purchaser must give notice of any defect to Monitor 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 shall not apply to any product which is repaired or altered outside of the Monitor Technologies LLC 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.

U.S. PATENT 6,696,965 B2

253A.4.0207

Global Flour Processor Uses Flexar® Guided Wave Radar

A large global flour processor and food products company recently began using the Flexar® guided wave radar in a total of eighteen (18) silos and bins to manage their finished product inventory.  Readings from these continuous level sensors is reported as being reliable and accurate, even during pneumatic filling, contrary to their previous measuring system.  A previous non-performing ultrasonic system was replaced by the Flexar level sensors.  Flexar guided wave radar level sensors were chosen as the best for pneumatically filled dust laden flour silos.

Eight (8) Flexar level sensors are installed in load-out silos that fill bulk trucks with processed and finished flour.  These silos are 12ft in diameter and 35ft tall.  The finished flour is pneumatically conveyed into these silos.  During filling the internal environment of the silos is very dusty and turbulent.  The finished flour in these silos is used for loading bulk transport trucks for distribution.  In addition, ten (10) Flexar level sensors are installed in 40ft high bins that contain bran.  This material is also sent by bulk transport to end users.

All of the Flexar level sensors are equipped with an RS485 digital communications output that is connected to a PC with a graphical user interface for inventory management purposes.  Monitor’s SiloTrack™ inventory management software is used by the facility to monitor and manage material inventories of both the finished flour and the bran.  SiloTrack allows for multiple user viewing and data access via LAN and this is how the facility will be using the software that provides a flexible, graphical user interface, alarms, report generation and history analysis functions.

Guided wave radar is especially well suited to level measurement applications of dusty powder materials even when measuring during pneumatic filling.  Flexar guided wave radar utilizes TDR (time domain reflectometry) technology.  Radar pulses are continuously transmitted down the sensor’s probe and guided to the material surface where they are reflected back to the electronics along the wave guide.  The time-of-flight of the pulses is measured and directly related to the distance to the material surface and its level.

>>Click here for more information about Flexar guided wave radar continuous level measurement sensors.
>>Download Product Bulletin 353A
>>Click here to visit our Flexar Website