IC40 COM Link issue related to Intelliph

[Usma92]

I have a Intellichlor IC40 and an Intelliph system hooked up to my pool for just over two years (pool is 4 years old. IntelliClor was installed with original equipment, I added the Intelliph 2 years ago). Last fall (October), I received a COM Link issue on my IntelliTouch panel under the diagnostics screen, and the "status" light on my Intelliph was red. When I opened the Intellichlor power center, I could smell a "burnt" smell. Upon visual inspection, I could see heat distress on some of the components (R13 on the DT+ terminal in picture) on the printed circuit board (PCB). I ordered a replacement, did an exchange and everything seemed to be functioning properly. However, the status light on the Intelliph was still red. I removed the panel from the intelliph and also saw some heat distress on the board (transistor bank to the right of RL 1) and one one of the connector pins (top row, third from left in photo). At this point the IC40 was working, so I disconnected the Intelliph and just ran the Intellichlor while I waited for a replacement panel for the Intelliph. I waited to install the new Intelliph panel once the weather warmed up and had the need to add acid. I installed the new panel in May and everything was running fine. After a few days, the COM Link issue reappeared, and I found the same issues on both the IntelliChlor and Intelliph boards. Pentair stated that it was probably a power supply issue, and that since my IC40 was ~4 years old, that it could be the issue as well. I replaced the Power Center, the IC40 and the Intelliph panel at the end of May. Within a few days, the COM Link error returned, and again both boards were fried! The only think I haven't changed is the motor on the Intelliph tank and pump assembly and the cable from the Power center to the Intelliph panel. I have replaced the PCB in the IntelliChor power center once again, but have not reconnected the Intelliph system. The system will run fine unless I hook up the Intelliph. I'm running out of parts to swap (money as well) and am looking for ideas. Pentair told me to change the power center again, which I don't plan on doing. They also don't seem to attribute any root cause to the Intelliph system, but that is where I believe the problem resides. Thanks for your time.

 

[kimkats]

Not good at all. It sure does sound like you know where the problem is but there is really no way to prove it

 

[ogdento]

Hi Usma92,

I don't have an intelliph or intellichlor, and I don't have an answer for you but I've dealt with loads of rs485 comm errors and maybe some of the following will help figure out what's going wrong...

In your top photo, next to RL1, what is that 8-pin chip? I'm guessing it's a max1485 or il81483 rs485 comm chip? - and if so then the two similar sized 2-terminal black rectangles between RL1 and the 8-pin chip are surge protection thyristors (one on each D+/D- line) that are supposed to help protect the comm lines against spikes and transients. What are their markings?

In the bottom photo, one of the protection devices on the comm lines is clearly burned up, so something very bad happened to it... this would usually be a big surge or a bad short to one of the power lines. What are the markings on the remaining protection device marked D8 (or D9), next to R14?

If both of the boards shown in the above photos have been replaced, were working at least for a little while but now are failing... then I would suspect either faulty cabling, a faulty power supply or some kind of bad power surge. It didn't blow up the moment you installed the new boards so the cause could be intermittent. I can't imagine how the motor would produce a surge on the comm lines but if it were faulty I suppose it could be interfering with the power supply (back emf from motors/coils can absolutely damage electronics).

Is there anything else connected to the comm bus with these two boards? As far as the cabling goes could there be a nick in the sheathing or some other fault in the cable that might short it only under certain conditions... have you experienced any heavy rain or lightning around the time of the latest fault?

What I see in the photos looks worse than the usual accidental short of D+/D- to the red power line on the comm port because that normally doesn't cause parts to burn up that badly, unless it was in that shorted condition for an extended period. A diode would normally only burn up like that if it experienced a reverse voltage or forward current that was way over spec.