A few comments on my RJ60+

[hexabc]

For the last several days the weather was pretty consistent - 85 to 90 degrees and sunny skies. FC at the end of 8-hours SWG run would be around 5 - 5.5 ppm, in the morning 4.5 - 5 ppm, CYA 70, SWG output 60%. The overnight loss of FC <= 1 ppm.

I tried to adjust the output to reach 6 ppm. So I increased it from 60 to 65%. My pool didn't react in a noticeable way. The next day I bumped it up to 70%, and again - no noticeable response. For both settings there were about 3 chlorination cycles: 2 hours ON - 1 hour OFF /2 hours ON - 1 hour OFF / 2 hours ON.

Today I set the output to 75% and got a very different timing. The cell stayed in ON state, producing chlorine, for about 4 hours, then it switched to OFF for less than an hour, and again to ON for the remaining time (these are aproximate numbers). At the end of 8-hours day FC reached 6.5 ppm.

This is a very unintuitive behavior. I think the switching frequency is just too low, making it hard to predict and adjust FC production. I don't see any justification for that, the algorithm is executed by RJ60's microcontroller software and a much higher frequency could have been implemented.

Having said that, if the SWG turns out to be reliable, and the cell lasts a long time, I will still be happy with it. Especially after switching to a VS pump and going with longer daily runs instead of 8 hours.

 

[Texas Splash]

You seem to be experiencing many of the same things as some of us. As you said, regardless of hourly or overnight expectations, as long as the cell is maintaining the FC we require over a 24 hr period it should be fine.

Circupool RJ-45 Production Test

Fellow RJ-45 owners, I am curious to know what type of FC production you are seeing with your SWG - specifically an overnight GAIN test. For my pool, just under 18K, the APP shows that my cell should provide ~3.9 ppm of chlorine in 7 hours at 100% output. I have conducted four overnight gain...

www.troublefreepool.com

 

[JoyfulNoise]

How are you measuring the cell generation time (ON time)?

 

[hexabc]

How are you measuring the cell generation time (ON time)

Just sitting on the patio with a beer, listening to music and checking the LEDs on RJ60 through binoculars from time to time

 

[markayash]

Just sitting on the patio with a beer, listening to music and checking the LEDs on RJ60 through binoculars from time to time

On for 3 beers off for 1. Wait it’s been 4 hours and I can’t remember

 

[JoyfulNoise]

Well, every manufacturer does their own thing in terms of duty cycle. It could be that the ON/OFF cycling just refers to when the chlorine is being generated and when the unit is ON, the actual cell current and reversal is on a much shorter cycle. These SWGs use a non-membrane bipolar cell so there’s no exact recipe for when to power up the cell and reverse polarity. It’s up to the manufacturer to figure out what works best.

 

[hexabc]

Well, every manufacturer does their own thing in terms of duty cycle. It could be that the ON/OFF cycling just refers to when the chlorine is being generated and when the unit is ON, the actual cell current and reversal is on a much shorter cycle. These SWGs use a non-membrane bipolar cell so there’s no exact recipe for when to power up the cell and reverse polarity. It’s up to the manufacturer to figure out what works best.

The cell's case is clear, it can be seen when chlorine (or rather hydrogen) is generated. The switching interval is really very long - it goes in hours. It seems that the correlation between output setting and actual production level could be better, if that interval was much shorter...

 

[Texas Splash]

Just sitting on the patio with a beer, listening to music and checking the LEDs on RJ60 through binoculars from time to time

 

[markayash]

Just sitting on the patio with a beer, listening to music and checking the LEDs on RJ60 through binoculars from time to time

 

[laprjns]

This is a very unintuitive behavior. I think the switching frequency is just too low, making it hard to predict and adjust FC production. I don't see any justification for that, the algorithm is executed by RJ60's microcontroller software and a much higher frequency could have been implemented.

I always wondered about the 180-minute cycle times until I found this thread from 2007 which had this explanation for long cycle times.

One important comment about driving cell with AC voltage is it's lifespan. Every time you revere the anode you damage it. Reversing cell every 1/50th of the second will kill it very quick. Anode material manufacturers usually state maximum reversal rate when the supply anode to SWG manufacturers. The rate fluctuates from 2 - 8 hours ( as maximum reversal infrequency). Reversing it more often will reduce the nominated by manufacturer lifespan.
The whole concept of manufacturing powersupply module to operate the cell is about making the cell last the distance. There is a number of specialized circuits and logic that operates the cell module the particular way to maximize it life. The reason why cell module so carefully looked after is the cost. The cell cost to SWG manufacturers as much as the rest of the machine. Not many people realize how hight tech the anode material is and how much it cost...

Regarding your other comments;
Changing the power level from 60% to 70% over 8 hours will only increase FC by 0.5 ppm, so I doubt you would notice the difference in daily readings. Maybe you would see the FC creep up a bit after a week or so.

The RJ60 uses, I believe, 180 minuted cycles, At a 75% setting it will produce at for the first 120 minutes of the cycle then rest for 60 minutes, then repeat the cycle. The SWG doesn't know that you will shut it off after eight hours, so running at 75% for 8 hours produces the same FC as running for 9 hours at 75%.
Regarding your observation that it produced for 4 hours and was off for one hour, there are only two possible explanations. One is that there is a problem with the electronic controller the other is that there is an issue with the beer.

 

[hexabc]

I don't know how to delete a response ... :-(

 

[hexabc]

I always wondered about the 180-minute cycle times until I found this thread from 2007 which had this explanation for long cycle times.
...

Sorry I missed the response. Very interesting link. I think that current reversal doesn't have to be in sync with the cell's duty cycle. Also, the thread is from 2007, when, I'm quoting: "specialized circuits and logic that operates the cell module the particular way to maximize it lifespan". These days software-driven microcontroller chips implement optimal SWG strategies - the sky is the limit and complex algorithms do not impact the price of the controller.

I'm not really trying to disparage CircuPool SWGs. As a matter of fact I am a happy customer. With the sunny weather, CYA at 70 ppm, 8-hour run and SWG's output set to 65%, the FC in my 24k pool stablized at about 6 ppm as measured early morning.