Dale I don't think you need a multiplexer. I guess it is the same with other systems. First do the ph measurement in a glass of water. If that is stable then your sensor is working right. If you do the same in your sump and you get eratic readings. Then you issue is that one of your electronic devices is leaking electricity in the water. Shut of all devices one after the other till the reading is stable. Then you have the device that is bad (probably a rip in the cable or something).
-------------------------------- Last edited Mon Feb 09, 2015 1:00 pm --------------------------------
Dale I don't think you need a multiplexer. I guess it is the same with other systems. First do the ph measurement in a glass of water. If that is stable then your sensor is working right. If you do the same in your sump and you get eratic readings. Then you issue is that one of your electronic devices is leaking electricity in the water. Shut of all devices one after the other till the reading is stable. Then you have the device that is bad (probably a rip in the cable or something).