Dosing Pump Programming Help

[LouH]

I'm looking for someone to lend me a hand doing some programming. I have not done this before, so some help would be greatly appreciated.

I'm attempting to set up two BRS dosing pumps to dose 2-part Ca and Alk solutions. I've done a trial to measure the actual flow rate through each pump and have determined how long each needs to run to achieve my daily dose targets for each solution.

My objective here is to have many small doses spread out over a 24 hour period to avoid abiotic precipitation, which is what I have now with another doser. I've calculated each doser's on and off times so that I achieve 4 dose periods per hour. Here is what I need:

Calcium Doser:

Needs to run for 2:14 and then be off for 12:46 and then repeat over and over to get 96 dosing events/day.

Alkalinity Doser:

Needs to run for 2:22 and then be off for 12:38 and repeat as stated above.

I do not want two pumps running at the same time due to the plumbing configuration, so the program would have to account for that as well. The greater time between the Ca and Alk dosing events the better (i.e. the alk doser would be running in the middle of the off time cycle of the Ca doser).

Again, any help would be greatly appreciated.

Thanks

Lou

[LouH]

Calcium Doser

OSC 000:00/002:14/12:46 Then On

Alkalinity Doser

OSC 007:30/002:22/012:38

I'm assuming that 000:00 is time marker midnight, so with the program above, the calcium doser comes on at midnight, runs for 2 minutes and 14 seconds, shuts off for 12 minutes and 46 seconds, then repeats this On/Off cycle 24 hours/day.

The alkalinity doser comes on 7 minutes and 30 seconds after midnight, runs for 2 minutes and 22 seconds, turns off for 12 minutes and 38 seconds, then repeats this On/Off cycle 24 hours/day.

By starting the alkalinity doser at 7:30, 5 minutes and 16 seconds have passed since the calcium doser stopped, essentially placing the 2 minute and 22 second alkalinity dose right in the middle of the Off period of the calcium doser.

Is my interpretation of the logic and function of this command correct?

Lou

[LouH]

Sorry, the alkalinity command should have read:

OSC 007:30/002:22/012:38 Then On

[erikkiehle]

Hi Lou, I'm a new user so DON'T suggest you try this unless others think it's appropriate.

I THINK the following might work for you.
For the Calcium outlet:
Fallback OFF
Set OFF
OSC 000:00/002:14/012:46 Then ON

For the Alk outlet:
Fallback OFF
Set OFF
OSC 007:26/002:22/005:11 Then ON

I THINK, this would do the following at midnight:
At:
00:00:00 Calcium outlet turns on
00:02:15 Calcium outlet turn off after running for 2:14 sec, all off for following 5m 11 sec
00:07:26 Alk outlet turns on
00:09:49 Alk outlet turns off after running running for 2:22, all off for following 5m 11sec
00:15:00 Cycle restarts and continues every 15 minutes through the day.

Can anyone offer feedback on my attempt at programming. I'd like to learn if this is appropriate or if there's a better way.

[erikkiehle]

Sorry, the alkalinity command should have read:

OSC 007:30/002:22/012:38 Then On

I think you have the right idea, but your overall time adds up to more than a 15 repeating cycle, so you need to shorten the last off timer to be 005:08, otherwise your Alk would come on for 2:22 out of every 22:30 period

[LouH]

Your written explanation is what I was trying to communicate but is much easier to follow. Thanks. That was what I was trying to say. You end up with 96 doses in a 24 hour period for both Ca and Alk.

Lou

[LouH]

I'll run the program overnight with Kalk topoff water and see what I get in the morning. I'll measure the container loss in weight over time.

[LouH]

Thanks for the clarification on the alk command. I'll run with that.

[LouH]

I think you have the right idea, but your overall time adds up to more than a 15 repeating cycle, so you need to shorten the last off timer to be 005:08, otherwise your Alk would come on for 2:22 out of every 22:30 period

I might be missing something here but under your program the Ca doses as it should. It runs for the programmed time, stops, and then some time goes by when neither pump operates. Then the alk dose pump turns on and runs its programmed time and stops. The issue is that the Ca doser then immediately starts again the second that the Alk doser stops. What happened to the no pumps running period of approximately 5 minutes between dosing cycles?

Lou

[LouH]

I had to modify a couple values and they now dose at the intervals that they should. I'll see in the morning how accurate my calcs were.

Thanks for the help.

Lou

[LouH]

Erik,

Your program was on the money. Nice job.

Lou

[ansek]

Erik,

Your program was on the money. Nice job.

Lou

I would suggest you put in a pH fail safe to prevent your pH from going through the roof. I have my two-part dosing setup to no dose if the pH is about 8.30.

I'm in the proces of having my two part dose 2mL every hour when my pH is below 8.31 and 0.5mL when my pH is above 8.30. This will reduce the current 0.53 meg/L Alkalinity swing I see each day. I just have to figure out how to make this happen. I think I'm going to use virtual outlets like so:

Virtual_1_1
OSC 030:00/001:30/028:30 Then ON
If pH > 8.30 Then OFF

Virtual_1_2
OSC 030:00/000:45/029:15 Then ON
If pH < 8.31 Then OFF


TwoPart_4_5
Fallback OFF
If Virtual_1_1 = OFF Then OFF
If Virtual_1_2 = OFF Then OFF
If Virtual_1_1 = ON Then ON
If Virtual_1_2 = ON Then ON

Thoughts?

[LouH]

My pH runs low, so I'm not concerned about high pH for now. I've been running a GHL doser for months now without issue. I changed over to the BRS dosers because of their low dose rates and the ability to be flexible with Apex programming. The GHL doser dose rate is faster than I like, and you don't have much in terms of options with regard to programming. I will use it for Mg dosing and automatic water changes. It will work fine for those purposes.

Regarding your proposed commands, I can't help you there. Yesterday was the first programming I've done on the Apex outside of setting up outlets to turn on or off in relation to pH, temp and/or ORP. Hopefully someone with some experience will lend you a hand.

Good luck.