Sign in to follow this  
Followers 0
kcor

gallons in totes

7 posts in this topic

have a question, have some chemical containers that we call totes, and they hold about 800 gallons each. they are mobile, to a point, what that means is that they are moved from one area of a plant to the other from time to time, they are not always stored together in a central location. They are filled by a outside chemical rep from large storage containers. Am wanting to put a sensor, most likely at the moment, a ultrasonic level sensor to be able to know and display how many gallons are in the tote. I know I can do this with a plc and some analog input cards, but was asked by the manager in the area if there was a way to just mount a sensor and have it connected back to a controller and just display the amount of gallons in the totes before they are filled, and how many gallons after they are filled. Has anyone done something like this using a level sensor such as ultrasonic level sensor and connected it back to some type of meter such as a red lion. I was thinking it may be possible to use a 4-20ma ultrasonic sensor, connect it to a redlion type controller, and calibrate the display on the red lion to display gallons based on the 4-20ma input signal. Any suggestions Thanks

Share this post


Link to post
Share on other sites
I have done it with PLC;s and SCADA with remote dial into sites to give a 24hr product usage profile and to prompt the end user to order some more... Back to your problem though i suggest that the meter should be able to have a resetable high (max) & low (Min) points... which i am sure could be a function of most common display meters (along with scaling)

Share this post


Link to post
Share on other sites
We use a lot of totes at my facility. I assume these totes are made to be moved by a fork lift truck, ours are. The easiest and most trouble free way to deal with these totes, is a scale. There are many mfgs. of floor scales that are made to accommodate pallet sized loads, they're portable, and can be moved to anywhere in the plant. No PLC required, display built right in, just have to know the density of the material, and produce a cheat sheet, showing weight versus gallons for the floor people to use. For filling you simply tare the scale, and then fill, the amount added will be displayed on the scale. Just a suggestion.

Share this post


Link to post
Share on other sites
I would think that this would be so common a request that someone would have made a portable handheld meter with an ultrasonic prox, that would be able to display the level of the tank. (taking into account the cross-sectional area of the tank)

Share this post


Link to post
Share on other sites
Actually, a scale makes a whole lot more sense than a level sensor. A level sensor will give you just that -- the level. It doesn't concern itself with the geometry of the tote. Surely, it's not just a pure cube or a pure cylinder. However, a scale will tell you how much is in the tote. Now the geometry of the tote doesn't matter. Plus, a scale will be much quicker and easier to configure -- and it's trackable.

Share this post


Link to post
Share on other sites
Thanks for suggestions. At the moment, it looks like i will end up using either a micrologix1200 or possibly a 1100 since it has ethernet and a small panelview, such as a 300 micro I have usese the 1200 on about a dozen small projects so far and used the analog expansion module, never done anything yet with the 1100 and analog, but i assume it should be similar to 1200. There will 8 totes, that hold 1000 gallons each of different chemicals.

Share this post


Link to post
Share on other sites
The original idea to use a level sensor to an indicator is great, particularly if the plant works in 'gallons', because level will provide a volumetric reading convertible to gallons. However, if the plant uses pounds or Kg as a mass unit (rather than volumetric unit), then a scale would be a better approach. Most indicators come with a transmitter power supply option to power the loop, too. The difficulty with an ultrasonic level transmitter is that all industrial ultrasonics have a dead zone (some call it a blanking zone) beneath the face of the transducer of about 1 foot, in which the device cannot read a return echo. The standard approach for getting around that is to use a 12" standoff. The limitation of a stand-off on a tote is the access point, I suspect it's bung hole sized, about 2" in diameter? For long shots (10M+), rule-of-thumb for a stand-off is 4 or 6" diameter. But a tote is short shot, and could very likely work well with a 2" pipe stand-of. I suspect Siemens Probe LU would work fine in a 12" stand-off of 2" pipe. Your local Siemens instrument distributor (not necessarily the Siemens PLC distributor) would probably let you borrow one to try it. Probe LU: https://pia.khe.siemens.com/index.aspx?Nr=11641 I've heard that others have used Flowline for short shots. Dan

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0