acjr probe faulty readings...

michaeljames · #1 12/24/2007, 06:51 PM

hey gang, just wondering if anyone else has had the same issues I seem to be going through, I have been getting really low readings from my ph probe awhile after hooking it up to my computer so i did the sensible thing and recalibrated my probe, no luck there... so next I went and bought a shiny new probe and calibrated that one as well. still nothing... I knew it was not just low ph as I tested with two different kits and even took a sample to CF. so my next step was to ask for some tech help at neptune seems they must not make enough selling the controllers because now if your bold enough to want to use your computer you have to buy more stuff (beyond the serial cable and software) now it seems I need an isolater to run between the unit and the computer... of course I looked at the website to price one, the only one I could find came in a combo kit for 200 bucks, anyone else have similar issues?
by the way hope you all have a merry christmas and a great new years!

LFS_worker · #2 12/25/2007, 02:27 PM

try installing a grounding probe right next to the pH probe. stray electricity will affect readings.

Also if you have your pH cables anywhere near a VHO, MH, cable it also will throw off readings.

Good luck mike!
Brian

rjrobert · #3 12/25/2007, 08:17 PM

The grounding on those probes is horrible. Look for what you have running around it. And as a Computer Engineer let me say as my opinion that isolaters are only needed in rare setups.

I should take a little you tube video and show you how I can change the PH reading of the AC3 by moving the wire around . Sounds like a good DIY project to replace the standard wiring with much better wiring, an only in the distance you really need.

just my 2 cents. Let me know if you can't seem to get it fixed I could try to stop over and help route your wiring to eliminate your issues. (assuming it is interference).

Merry Christmas

rjrobert · #4 12/25/2007, 08:40 PM

Also - Try this.
Unplug the BNC of the ORP Probe from the AC. See if that fixes the issue. I did have to do that. For some reason when I had the ORP Probe pluged in it freaked out the PH Probe. Since ORP (in MY oppinion) is largely useless to monitor I never complained to Neptune about it. Also Make sure you have the PH Probe in the PH connector. That seems silly but I've seen two different people do that, One of them owns a fish store here in Rochester. The ORP probe will register in the PH connector, although the reading will be WAY WAY off.

Just wanted to send that in since I just remembered I had that problem with my AC3 a while back.

Merry Christmas again.

michaeljames · #5 12/26/2007, 08:55 AM

thanks Rob! I don't have the ORP probe, and I disconnected the serial port to the computer and the PH reading shot up to where it should be... now I just need to figure out how to get it to read correctly plugged in! hope you all had a great christmas!

chrisguy · #6 12/26/2007, 01:07 PM

You need a Ground Isolated Serial Connector.

Description:
The ground isolated serial connector (SERIPC9) is used to break ground loops between your PC and the AquaController. In some installations a ground loop is formed when a serial connection is made and can cause erroneous pH and ORP readings. This ground loop can be broken by installing a GISC in the series with the serial cable from the AquaController. If the serial cable is going to be permantly hooked up to the AquaController, then the GISC is recommended. The GISC measures 1.5" x 1.25" x .65" and has one male DB9 connector and one female DB9 connector. Note that the GISC is only for use with the AquaController, AquaController 2 or AquaController Jr.

Premium Aquatic has them for $39.95
http://www.premiumaquatics.com/Merch...Category_Code=

Search PA's site for NEP-SERIPC if the link doen't work.