Support - FAQ - Application and Use of Product
Q:
How do I select the best sensor for my bulk solid point level application?
A:
There are several criteria that need to be considered. Please refer to our White Paper titled “Application Considerations for Point Level Monitoring of Powders and Bulk Solids”. You can also Contact us to discuss your application with a technology and application expert.
Q:
How do I select the best bulk solid CONTINUOUS level or Inventory sensor?
A:
There are several criteria that need to be considered. Please refer to our White Paper titled “Application Considerations for Continuous Level and Inventory Monitoring of Powders and Bulk Solids”. You can also Contact us to discuss your application with a technology and application expert.
Q:
When is the best time to consider a capacitive proximity switch?
A:
The best time to consider a capacitive proximity switch is when you need a small sensor because space in the mounting area is very limited, the material is dry and free-flowing or a clean non-sticky liquid, and the switch output is not required to switch a heavy current load, perhaps just to be used as an input to a PLC. The Model CPH Capacitive Proximity Switch, when the application meets these criteria, can also be one of the lowest cost sensors. Refer to our White Paper previously mentioned regarding application considerations for point level sensors for further information. Don’t forget to check our entire Media section for other resource materials that may offer more information.
Q:
What is “fail-safe”?
A:
"Fail-safe" refers to the position of the relay output should power to the sensor fail. In case of a power failure the relay output will go into the Alarm condition, whether the point level sensor is used for High level detection (material presence = alarm) or Low level detection (material absence = alarm). Refer to the product Installation, Operation and Maintenance instructions.
Q:
How do I select the correct “fail-safe” setting?
A:
There are two possible “fail-safe” settings, High and Low. You select the one that matches your application, or how you are using the point level sensor. If you are using the sensor as a High level sensor where detection of the presence of material is your Alarm condition, then choose the “High” fail-safe setting. If you are using the sensor as a Low level sensor where detection of the absence of material is your Alarm condition, then choose the “Low” fail-safe setting. Refer to the Installation, Operation and Maintenance instructions of the specific sensor you are installing for more information.
Q:
Why are so many “paddles” available for the Model RH/RHX bin level indicator?
A:
The Model RH/RHX is a rotary paddle bin level indicator. The "paddle" that attaches to the output shaft performs part of the sensing function as it impacts the sensors' sensitivity to a variety of material bulk densities. The Model RH/RHX Rotary Paddle units can sense the presence of powders and bulk solids with densities ranging from 5 pounds per cubic foot to over 100 pounds per cubic foot. This wide range of sensing is accomplished by the choice of the “paddle” that is attached to the output shaft. Six (6) paddles are commonly available. The choice is simply based on bulk density, particle size and whether the paddle needs to be inserted in through the mounting coupling or if a mounting plate accessory will be used. BlueLevel Technologies offers folding insertable paddles, standard insertable paddles and conventional multiple vane paddles.
Q:
Why is there AC and DC capacitive proximity level switches?
A:
A Capacitive Proximity Switch senses the presence/absence of material using capacitance sensing principles. The sensor uses a solid state switch output. The output can be provided to switch either AC or DC loads. This is why there are both AC and DC proximity switches. An AC switch is used if you are switching an AC load and a DC switch is used for switching a DC load. Refer to the Media section of our website for a White Paper on Capacitive Proximity Switches for Level Sensing for further information.
Q:
Why use a vibrating fork over a vibrating rod?
A:
Generally speaking the advantage of a fork over a rod is price and sensitivity. However, vibrating rod devices have become very competitive. Rod units promise better performance with materials that are NOT free-flowing. This may be true, depending on installation orientation and the application. In the majority of applications where the material is relatively dry and free-flowing, the fork and rod can be found equal in performance. For low density materials the fork also proves to be lower in price and can be better performing as well.
Q:
When should I consider using a vibrating fork sensor?
A:
Refer to the White Paper previously mentioned regarding application considerations for point level sensors for more information. Vibrating fork point level sensors are superb alternatives to RF Admittance or Capacitance level sensors because they do not require tuning or calibration adjustment. Vibrating fork point level sensors also can detect the presence of a wide range of bulk density materials, many of which cannot be detected by any other technology. Don’t forget to check our entire Media section for other resource materials that may offer more information.
Q:
What applications should the rotary paddle bin level indicator NOT be considered?
A:
Obviously materials of construction compatibility with the process media and also process and ambient temperature limits must be considered. Other than those limits, the rotary paddle units can be used with an extremely wide range of powder and bulk solid applications and even some liquid or slurry applications where the unit power pack and process connection area will never be immersed in the fluid. Refer to the White Paper previously mentioned regarding application considerations for point level sensors and don’t forget to check out our entire Media section for other resource materials that may offer more information.
