AC II & Temperature Readings

[Budman912]

I've had my AC II, standard temp probe, Aquanotes 3.1 running on a computer that is constantly connected to the AC II. I don't have the ground isolated serial connection. I have my AC II set up to take readings every 10 minutes. Readings are fine and consistent until I go to my computer and wake it out of hibernation to looks at the logs in Aquanotes. My temp reading drops by about 5 degrees. It slowly rises from there back to the correct reading. My question is does not having the ground isolated serial connector affect the temp readings also. All I have read is that it affects the ph and orp probes. I havn't hooked those probes up yet so don't know if I'm having an issue with those yet.

[Budman912]

I also just hooked up my ph and orp probes. My ph is reading fine, but my orp is reading 000. Anybody know why this is happening?

[clp]

Unplug the serial cable and see if the readings change. If so there is a ground loop, and you need an isolator. The pH probe is blue and the ORP probe is red - just in case they are connected incorrectly.

Curt

[Budman912]

Thanks Curt. That was the issue. I will order a ground isolated serial connector.