Help with Water Pump

It is just the pumps which draw significant current. The control circuit itself draws < 1 mA on average (tens of mA at the instant of switching a pump...but for < 200uS).

Please forgive me in advance, but I've got a question.

First, though, I should say that I recently retired from the SC DNR, where I worked at the Marine Resources Research Institute here on James Island.

Over the years we had many different fresh and salt water aquaria, from as small as a petri dish up to tens of thousands of gallons (large animal, brood stock and grow out holding tanks).

One in particular, a seawater coral reef (100 gal) on public display, was probably the most difficult to maintain (coral being more than extremely picky about their environmental conditions).

In all these cases, except where we were simulating 24 hr tidal flow conditions, the water circulation was kept at a constant rate, 24/7/365.

So, my question is: Why are you needing to pulse your pumps?

In all these cases, except where we were simulating 24 hr tidal flow conditions, the water circulation was kept at a constant rate, 24/7/365.

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This is just an educated guess based on what I know and what the OP has told us but.... The tank turnover rate, the rate at which all the water will be replaced or reprocessed will likely be a constant, like the systems your familiar with. The pumps the OP is installing now will be to stir or agitate the water that's in the tank. This more closely simulates the natural water conditions of a real reef.

The ocean is basically infinite, meaning the water chemistry almost never changes. The OP's tank is not, so the water needs to be constantly monitored and adjusted. This would be the whole tanks turnover rate and will be handled by external filters and water conditioners and such. The ocean is also very turbulent around a reef, this would be the agitation factor needed and will be handled by the pumps that the OP is trying to install now.

I'm really unfocussed right now so I could be completely wrong. In any case, that's my assumption.

I do recall a tank that had a water wheel in line with the inflow recirc water jet that powered a vane the constantly diverted the flow left and right, thus creating a good deal of cross current and turbulence in the tank.

Just a thought.

For my part, I guess I'm thinking of my having been called the Over-Engineer a lot of times (entirely deserved) and as a result, always looking for ways the avoid the moniker.

()blivion, you hit the nail on the head. Generally speaking, corals need a chaotic back and forth motion of water.

Besides the parts shown in trhe schematic in post 36, I'm getting Kester 60/40 22swg solder, prototype board, alligator clips for heat sinks, some braided solder wick, did I miss anything essential? I have a soldering station, a magnifier with a "third hand", and a multitester. I'll get or make a metal box after I see what size this thing turns out to be.

The IC CD40106B has 14 pins-which two pins should I connect?

There are four 1meg pots. Two of the 1meg have wiper=.8, one has wiper=.7 and one has wiper=.9.

There are four 500K pots. Two of the 500K have wiper=.5, one has wiper=.6 and one has wiper=.4.

Do I need to set the wipers on the pots?

The IC CD40106B has 14 pins-which two pins should I connect?

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Pin 14 = Vdd = +V; pin 7 = Vss = ground. The other pins are shown in the attached. Note the notch (or dot) on the IC, to identify the chip end where pins 1 and 14 are. Use whichever 4 of the 6 gates in the IC which you find convenient. The inputs of the two unused gates should be connected to either +V or to ground.

Do I need to set the wipers on the pots?

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Yes, to set the on or off time to whatever you want. (The numbers .8 etc are just for the simulation).

did I miss anything essential?

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Looks like you got it all figured out. Incidentally I have built similar circuits literally with nails and tin foil on a 2x4 before. So... I think your safe.

Joe

If you have any problems finding or getting parts let me know.

Ron In Cleveland.

Incidentally I have built similar circuits literally with nails and tin foil on a 2x4 before.

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I have shoot fireworks like that before.

alec_t said:

Pin 14 = Vdd = +V; pin 7 = Vss = ground. The other pins are shown in the attached. Note the notch (or dot) on the IC, to identify the chip end where pins 1 and 14 are. Use whichever 4 of the 6 gates in the IC which you find convenient. The inputs of the two unused gates should be connected to either +V or to ground.
Yes, to set the on or off time to whatever you want. (The numbers .8 etc are just for the simulation).

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Thanks Alec. Do you mean the attached from your post # 20? I apologise for still not understanding how to hook up the CD40106B. Thanks for clearing up the pot wiper adjustment.

()blivion said:

Looks like you got it all figured out. Incidentally I have built similar circuits literally with nails and tin foil on a 2x4 before. So... I think your safe.

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I guess looks can be decieving . Sounds like the kind of circuit I colud fall in love with.

Reloadron said:

Joe

If you have any problems finding or getting parts let me know.

Ron In Cleveland.

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Thanks Ron, I spent a little time today chasing down a CD40106B. An outfit in Canada is going to quote me by email tomorrow. Too bad the plan does not call for a regular CD40106. Everyone has those for sale. Just curious, what does the CD40106B do that the CD40106 does not?

Do you mean the attached from your post # 20?

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Post#36 (pumps individually controlled). If you wanted the post #20 arrangement (pumps in pairs) then you would only use 2 of the 6 gates and the unused 4 gates would all need their inputs connected to +V or ground.

Too bad the plan does not call for a regular CD40106

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Any CD40106 will do, regular or not ;-) Just make sure you don't use a High Speed (HCMOS) version (which can only work with a 5V supply).

That's terrific, I just got an email from Canics & they can't find any CD40106B.

"Pin 14 = Vdd = +V; pin 7 = Vss = ground. The other pins are shown in the attached."
I don't have the parts yet-is the attached a diagram that will come with the IC?

And yes, I am working towards the schematic in post 36 to control all four pumps independently.

https://stores.ebay.com/Tayda2009/_i.html?_nkw=+circuit+board&submit=Search&_sid=872591586

I wonder if you guys could take a look at this variety of circuit boards and give your opinion which would be the best fit for my project.

I'm looking at capacitors and noticed that 100uf and 10uf both come in a variety of voltages. What voltage will be my best choice?
Capacitor C3 and C5 on the schematic from post 36 look like they have a value of 100m, is that right?

The 10 ohm resistors I found are 1/4w, 5% carbon film. Will that do?

is the attached a diagram that will come with the IC?

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Oops! I meant to attach a pinout pic. Better luck this time.

What voltage will be my best choice?

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As the timer circuit is running from 12V I would go for 25V (or more) working for the caps.

a value of 100m, is that right?

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No, its 100n (nanoFarads). 100nF = 0.1 microFarads.

The 10 ohm resistors I found are 1/4w, 5% carbon film. Will that do?

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Perfectly.


Edit: One thing you will need, which hasn't been mentioned, is terminal blocks/plugs/sockets suitable for connecting the circuit board in the screened enclosure to the outside world.

https://stores.ebay.com/Tayda2009/_i...._sid=872591586

I wonder if you guys could take a look at this variety of circuit boards and give your opinion which would be the best fit for my project.

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Generally speaking, you want the smallest board that your project will fit on. That being said, you'll never know exactly how big it will be until you build it. Also note that some of those purchases are more than one board. With the proper arrangement you could prolly fit this project on any of those boards IMO. But you might as well get the biggest single board they have. You can always cut it smaller if need be.

As for which board type, I personally prefer the non-stripeboard, as opposed to the "veroboard" (stripboard). If you do get veroboard you have to be aware that you need to cut the strips with a razor every so often when making your circuit or you'll get shorts. With the board type that's just a bunch of plated holes you don't have to do this. You'll instead have to run wires from point to point around the circuit making connections deliberately, which I feel is much less prone to error than the alternative. You also have to run wires with the strip board, just not nearly as much. I also wouldn't get the "silver" ones (Tin plated) as they don't appear to be very main stream to me. It doesn't matter either way. It's totally up to you which you chose. In reality you can do this project with either board type just fine I'm sure.

Thanks Alec for that good info and the diagram. I was going to scavange the connector for the pump from the controller supplied with the pump and then see what kind of connector is needed to plug in the transformer. I appreciate your help staying on top of these details.

Thanks ()blivion for the tips on the boards. I agree with making every connection deliberately. I'm going to get everything ordered by this weekend and once it's all here start the build.

It occurs to me that your pump motors might under some conditions act as reverse voltage generators. To protect the FETs from such voltages it would be advisable to add some further diodes to the circuit. I've attached a revised circuit showing these (D13-D16). I've also identified the d,g and s terminals of the FETs and some pin numbers for the CD40106 and removed some of the text which related to the simulation.

Edit: I corrected post #96. 100nF = 0.1uF
Note that C2 should be a 50V working cap, not 25V as I said previously. The other 100uF caps can be 25V.

Thanks, you are awesome!