Bidirectional tidal flow - Page 2

sphelps · #11 12-07-2010, 05:24 PM

Quote:

Originally Posted by MitchM

LOL.

It sounds like it might boil down to another reeflo pump.
Now I need to find out how they stand up to constantly turning on and off.

I did find a 2" solenoid w/valve on the 'net, for a measly $2200.00.

Mitch

Yeah that will be your best bet. Turning on and off with the duty cycle you're proposing will be fine. The pumps are basically the same as those used in hot tubs which turn on and off way more than that.

Yeah and don't forget to multiple that number by at least 4 as that's the minimum number you'll need for the system if running a single pump. OM may do custom work as well but I can't see how one of those systems, customized or not, will work for you. They just use timing motors to rotate drums and syncing a bunch of them to work together the way you want will be impossible. Unless you had a common suction and two different outputs on each side of the tank with a drum that rotates to the two outputs. You'll still need some kind of timer to turn the motor on and off to provide the pattern you're looking for and to get it right it will also need limit switches to keep track of the drum position. Even if OM would do this the cost would be way more than $500.

golf nut · #12 12-07-2010, 05:24 PM

You can buy an $8 reed switch, sense the position of the drum then hook that to an Areotronics timer, select the time delay and you are done like dinner. net cost $39 .

MitchM · #13 12-07-2010, 05:32 PM

Codfather, thanks!

golf nut,

So I would use a 2-way OM unit?
What is a reed switch and Areotronics timer?

Thanks,
Mitch

sphelps · #14 12-07-2010, 05:41 PM

A reed switch works on magnetism, same type of switch you'd find on windows and doors for alarms. Problem is the OM has a thick plastic casing and you'd need pretty powerful switch to work properly and you would have to enclose one end within the drum which offers will space. Plus you'd need two switches for the two positions meaning you'll also need a smart relay to understand the two switches and control the system accordingly. It's certainly not as simple as described and the cost would be beyond $39.

sphelps · #15 12-07-2010, 05:45 PM

Not to mention the OM drum is driven by powerful magnets, I can't see a reed switch working properly to begin with.

lastlight · #16 12-07-2010, 05:50 PM

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

Overall likely cheaper to use a pair of DC controlled pump for each side. Red Dragon is apparently releasing new pumps as the previous generation had issues. I've heard good things about similar pump but can't quite recall the maker or the name sorry.

golf nut · #17 12-07-2010, 05:53 PM

How did I edit your post?

golf nut · #18 12-07-2010, 05:55 PM

Quote:

Originally Posted by lastlight

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

If you are only switching every 5 hours they will work fine, the rapid sequencing is their downfall.

sphelps · #19 12-07-2010, 05:58 PM

Quote:

Originally Posted by lastlight

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

If you had a common suction 2 valves would work. I think ideally to create the cross flow you need a suction on one side and the output on the other so in this case you would need 4, which is what I was talking about.

MitchM · #20 12-07-2010, 05:59 PM

Quote:

Originally Posted by golf nut

How did I edit your post?

Maybe because we're in the Vendor forum?

Mitch