Am I correct in thinking the rdf drum only revolves when the level sensors bring on the spray jet water pump to wash?
Garfield.
Some electronics are overly complex and others are pretty straightforward as well. Take a look at any industrial system that needs to work 99.9% of the time and it will use simple electronics typically powered by a simple PLC. Not saying an RDF is a nuclear power plant but no reason to argue like a Luddite either. Everything has advantages and disadvantages. The problem with the KC is just that the early versions are a steaming pile of sh*t not that it uses electronic and/or sensors.
The reason I ask the all the questions is... I decided to go the washing machine way.
I bought a couple of s/steel rotating drums with the axle spindle and the housing for the two bearings with double seals This section attaches to the inner s/steel drum.
It all fits into an alloy housing bolted to the outside of the enamel drum.
The shaft with bearings and seals pass through the housing.
The seal faces ride on a brass collar/sleeve at the base of the shaft.
The two alloy sections are convex or concave offset anyway?
I could not work out how to create the bent backing for outer housing to be bolted onto.
I cut the enamel drum along the back swedge/swage or overlap.
I now have a concave mould/mold of the inside of the washing machine drum housing.
Waxed and poured fiber glass mould/mold release agent into it.
Built up the molded backing with layers of chop strand and resin
So far so good with a strong s/steel drum support which will take care of the back seal bearing housing and the two s/steel drums angle/ drive shaft.
I bought On/off stop start buttons, emergency stop switch , timers, relays and water level controls from Alibaba.Chinese ebay
Omron controls made in Japan. Stupid cheap including postage.
The enclosure / housing will be out +- 2 mm 316 s/steel bent up and tig welded as per Profi drum design.
The drum motor will be a 4 rpm braai /barbeque spit motor, capable of turning a 25 kg sheep carcass.
Then a EUREKA moment. It took a long while for the penny to drop regarding the concave drum support
It was an rdf on hold for TOO long a time.
Now for drawings and quotes to get the the housings made up
Garfield
Last edited by coolwon; 05-30-2017 at 02:47 AM.
Last edited by kimini; 05-30-2017 at 04:33 PM.
Author of Midlana, Build this High Performance Mid-engine Sports Car. http://midlana.com/stuff/book
I don't consider what I bought as electronics they are push and pull replaceable controls by a layman.
Are the printed circuit boards in post 16 and a couple of post above that really necessary in a garden enviroment driving a RDF filter when your pond and the inhabitants are
in danger
You are running around like a chicken without a head trying to find a rocket scientist to get the equipment up and running ASAP.
Surely all that is required is a couple of pined timers, relays and level controls as standby for the hobbyist to pull and push at
Different story if it's a pump or drum motor.
They aren't exactly an arm and a leg to have on the shelf either as stand by as some posts advocate.
Cheers
Garfield
Looks like a fun project for a skilled tech like yourself. Garfield does have valid points. There are commercial drum filters currently running that use simple level switches and simple socket plug in ISO timers and relays with LED indicators.
I wonder what a out of warranty Profidrum controller costs if one gets fried vs a few ISO plug in timers and relays that can be serviced and troubleshooted by the average homeowner using the LED indicator lights?
Definitely a very interesting thread and you are very skilled and knowledgeable.
Like I've stated earlier in the thread I'm beginning to see how mechanical relays, timers and switches are all that's needed for this type of system but I'm a software engineer and things that interact with software are way simpler for me to understand than switches, relays and timers etc.. I know it doesn't make much sense but I've spent a career mastering software complexity so that's where I feel at home. If anything this project is making me wish I had majored in EE at University instead of Computer Science because I'm just now discovering the industrial automation world and it's fascinating but I'm starting from scratch learning Electrical Engineering 101.
When I think about it I can actually make a redundant system with failovers much easier in software than I could wiring up a bunch of relays and switches in series. Again just the way my head works. Ultimately I want to be able to design something with perhaps redundant sensors as backups and create a watchdog that can notify if anything is off with the control unit, drum motor, water level or sensors. That level of logic is much easier in software.
At the end of the day it's a great learning experience.
I am learning a lot from the posts. Keep up the good work.
I applaud rayrod for going this route. Let's face it, we live in a connected world. I believe, eventually, the professionally manufactured RDFs will one day have the features that you are trying to build.
I mean, who wouldn't want data logging, wifi connectivity to signal you when the unit malfunctions, or even turn on a valve to bypass the rdf it breaks...the sky's the limit when you are using these microcontrollers.
As far as maintenance is concerned, the parts that rayrod is using is just as easy to obtain as the ones used in simpler designs. These are not exotic parts! Since rayrod is the one that built it, he would not need a rocket scientist to figure out what was broken.
True, this project is not for your average DIYer. It requires a combination of good software, hardware, and electronics skills. I think this is a very exciting project, and I am very much enjoying the updates.
All the parts on this model KC-30 save for the Bell transformer are from either China, Korea or Vietnam which would make sense considering KC is from Indonesia I believe.
I think you are missing one important sensor, the failsafe sensor. In the event of clean-side water level dropped to a critical low and won't be able to get back to the normal level. For instant the drum is super dirty and multiple cleaning cycles still could not clean the drum enough to handle the flow. The water level in this case will keep dropping while the cleaning cycles keep running which could results in some serious issues such as:
1- Electronic components burnt out
2- Not enough clean water for pump/jet pump
3- Water on the clean side dropped too low while the drum full of dirty water's still turning with its full weight which may damage the drum barring.
The failsafe sensor in this case will cut off the power from the controller and temporarily stop the operation (no more cleaning cycles running until the water level back to the good level)
Kevin