What metal OK for RO water?

[midgetwaiter]

You are making this harder than it needs to be.

Your membrane flush is on the waste water side so you never come in contact with RO and it goes down the drain anyway, so it doesn't matter.

In order to switch the RO on and off to fill your holding tank I'd seriously suggest switching the input water. If you switch on the output side you will need to use an RO safe valve and you have increased leak potential because the unit will be pressurized. There's at least twelve points on a pressurized RO/DI unit that could fail but it you shut off the feed you only have one fitting that has any pressure.

[banditpowdercoat]

Originally Posted by midgetwaiter

You are making this harder than it needs to be.

Your membrane flush is on the waste water side so you never come in contact with RO and it goes down the drain anyway, so it doesn't matter.

In order to switch the RO on and off to fill your holding tank I'd seriously suggest switching the input water. If you switch on the output side you will need to use an RO safe valve and you have increased leak potential because the unit will be pressurized. There's at least twelve points on a pressurized RO/DI unit that could fail but it you shut off the feed you only have one fitting that has any pressure.

OK, Heres the deal.
This is for an automation of a 4 tank setup. The setup is going to be PLC(Programmable Logic Controller) controlled. The RO unit WILL have a main Solenoid controlling inlet. But also solenoids to run the RO unit for 20 min before filling the Main reservoir. Also, there will be a Run timer that after X hrs of water making, the RO unit will go into a Membrane Flush mode. When the reservoir gets to a pre determined level, the PLC will control the RO unit for a Purge, and fill of the Res. The PLC will also control independent level of 4 tanks. With this PLC, there will be safety timers for maximum RO run time as well as level control is managed bu Ultrasonic non contact level sensors. Nothing to stick, no salt creep to worry about etc.

Once this is complete, I'll be making a lighting program with another PLC.

I LOVE designing and building things

[golf nut]

Originally Posted by banditpowdercoat

OK, Heres the deal.
This is for an automation of a 4 tank setup. The setup is going to be PLC(Programmable Logic Controller) controlled. The RO unit WILL have a main Solenoid controlling inlet. But also solenoids to run the RO unit for 20 min before filling the Main reservoir. Also, there will be a Run timer that after X hrs of water making, the RO unit will go into a Membrane Flush mode. When the reservoir gets to a pre determined level, the PLC will control the RO unit for a Purge, and fill of the Res. The PLC will also control independent level of 4 tanks. With this PLC, there will be safety timers for maximum RO run time as well as level control is managed bu Ultrasonic non contact level sensors. Nothing to stick, no salt creep to worry about etc.

Once this is complete, I'll be making a lighting program with another PLC.

I LOVE designing and building things

why not build the whole thing out of polymers and drive it with buried magnets

[banditpowdercoat]

Originally Posted by Mr OM

why not build the whole thing out of polymers and drive it with buried magnets

I could, but wheres the challenge in THAT????

[Pescador]

I'm using parts from these guys, maybe you can source them elsewhere.
http://www.spectrapure.com/St_PTD_p0.htm

[mark]

bandit, not to highjack but in you controller plans have you considered continuous water changes such as RC TOTM,

(how it's not a highjack is you would need SW compatible valves and for sparing etc, might be easier just to go with one type of valve)

[banditpowdercoat]

Yes auto water changes are also in the thought stages. I just havn't figured out how to effectively keep a mix of fresh SW made. What would be the cat's Meow would be to have a Salt hopper and a auto salt adder. SG meter feedback yo a auger feed style hopper. Wonder if I can make THAT fit under the kitchen sink LMAO.


Incase someone wondering, I do not mind working on my tanks, in fact, I love it. BUT, I work out of province for 21 days at a time. The Mrs is also buisy, with going to school, and raising our Daughter. The automation is as much for her ease, as it is my need to tinker. I know I am going WAY overboard, but what is Marine Aquaria without Excess????