New Conductivity probe going haywire...

[coralcruze]

So i decided to purchase a new Conductivity probe because my old one was 3 years old and I thought it might be going bad as it was showing low salinity for months @ 33-33.5 (slightly low anyway)... I thought this was unstable, oh man, the new one is 10x worse.

the new probe comes in and after three calibrations It will not hold steady and getting different offset readings during calibration. is this a bad probe? going to try puting the old one back on and see if it stable. checked for stray current with my multimeter and see no stray current at all.

any suggestions of what I should try?

 

[Ariel V Rosa]

So i decided to purchase a new Conductivity probe because my old one was 3 years old and I thought it might be going bad as it was showing low salinity for months @ 33-33.5 (slightly low anyway)... I thought this was unstable, oh man, the new one is 10x worse.

the new probe comes in and after three calibrations It will not hold steady and getting different offset readings during calibration. is this a bad probe? going to try puting the old one back on and see if it stable. checked for stray current with my multimeter and see no stray current at all.

any suggestions of what I should try?

Sounds like you might have issues at the BNC connector on whatever you have it hooked up to. Is it an aquarium controller? Or a portable PH meter? If it's a portable meter, check that the BNC port has not become damaged and the solder points came apart in a way not visible to the human eye but enough to give you random readings since it's not getting a good connection. If its an aquarium controller then I would check for the same isues with the added step of salt creep and moisture some how making it's way in there. The likeliness of two probes displaying the exact same symptoms is astronomically high. So that would lead me to test and check the equipment the probes are being hooked to.

 

[Breadman03]

I would also add that electrical interference along the probe wire can be a big issue. Make sure that you keep the wire away from things like lighting ballasts and cords, big pumps, etc.

 

[RFL]

Is your probe connected to an Apex? I had a similar situation with a new conductivity probe connected to my Apex so I contacted Neptune Customer Support. They sent me a procedure to reset the conductivity port. I followed the procedure - problem solved.

 

[coralcruze]

Is your probe connected to an Apex? I had a similar situation with a new conductivity probe connected to my Apex so I contacted Neptune Customer Support. They sent me a procedure to reset the conductivity port. I followed the procedure - problem solved.

Yes it is connected to Apex.. I did the same as you and contacted them...HOWEVER, problem not solved.

I would also add that electrical interference along the probe wire can be a big issue. Make sure that you keep the wire away from things like lighting ballasts and cords, big pumps, etc.

its away from all other wires as its going through the center of the room to the tank and still an issue.

Sounds like you might have issues at the BNC connector on whatever you have it hooked up to. Is it an aquarium controller? Or a portable PH meter? If it's a portable meter, check that the BNC port has not become damaged and the solder points came apart in a way not visible to the human eye but enough to give you random readings since it's not getting a good connection. If its an aquarium controller then I would check for the same isues with the added step of salt creep and moisture some how making it's way in there. The likeliness of two probes displaying the exact same symptoms is astronomically high. So that would lead me to test and check the equipment the probes are being hooked to.

conductivity probe does NOT have a BNC connector.

 

[Ariel V Rosa]

conductivity probe does NOT have a BNC connector.

Regardless of connector the same issue can arise with any connector, if the part that it plugs into is having intermittent electrical issues the read signal will bounce around like crazy. I came at this not knowing what you have this thing plugged into, sure Apex doesn't use a BNC connector there, others do. So from a diagnostic point of view, I would treat it as an intermittent signal issue and check the solder points of the connector and check for any corrosion inside of the connector itself, maybe even reflow them if you are out of warranty, or just send the unit in for service.

Sometimes issues like this arise inside of the terminal compression mechanism due to of brand use of products that "can plug" into there, and they have different dimensional tolerances. Deflecting the connection points beyond their deflection reset range and causing it not to clamp down when you do go back to an approved product that was designed with the tolerances in mind.

TLR Steel dowel goes in hole, pushes against steel spring, put steel dowel into hole bigger than normal and the spring gets pushed beyond where it can recover from, it won't ever make good contact after the first time. Check the port it self if you have the ability and tools to, if not the unit probably needs some TLC from APEX. Some ports are not designed to be connected and disconnected on a constant basis or be moved constantly (BNC is designed for constant movement and disconnects and reconnects)

With that out of the way, have you let the probe soak for a week in the sump before calibrating it? proper calibration of the probe is nearly impossible or just difficult if the probe hasn't had time to set before being calibrated.

https://forum.neptunesystems.com/showthread.php?19228-Salinity-probe-doesn-t-match-my-reads
https://forum.neptunesystems.com/sh...y-Stable-Please-Help&highlight=salinity+probe
https://forum.neptunesystems.com/sh...linity-and-PH-probes&highlight=salinity+probe

 

[coralcruze]

Regardless of connector the same issue can arise with any connector, if the part that it plugs into is having intermittent electrical issues the read signal will bounce around like crazy. I came at this not knowing what you have this thing plugged into, sure Apex doesn't use a BNC connector there, others do. So from a diagnostic point of view, I would treat it as an intermittent signal issue and check the solder points of the connector and check for any corrosion inside of the connector itself, maybe even reflow them if you are out of warranty, or just send the unit in for service.

Sometimes issues like this arise inside of the terminal compression mechanism due to of brand use of products that "can plug" into there, and they have different dimensional tolerances. Deflecting the connection points beyond their deflection reset range and causing it not to clamp down when you do go back to an approved product that was designed with the tolerances in mind.

TLR Steel dowel goes in hole, pushes against steel spring, put steel dowel into hole bigger than normal and the spring gets pushed beyond where it can recover from, it won't ever make good contact after the first time. Check the port it self if you have the ability and tools to, if not the unit probably needs some TLC from APEX. Some ports are not designed to be connected and disconnected on a constant basis or be moved constantly (BNC is designed for constant movement and disconnects and reconnects)

With that out of the way, have you let the probe soak for a week in the sump before calibrating it? proper calibration of the probe is nearly impossible or just difficult if the probe hasn't had time to set before being calibrated.

https://forum.neptunesystems.com/showthread.php?19228-Salinity-probe-doesn-t-match-my-reads
https://forum.neptunesystems.com/sh...y-Stable-Please-Help&highlight=salinity+probe
https://forum.neptunesystems.com/sh...linity-and-PH-probes&highlight=salinity+probe

You make alot of good points here that no one suggested. especially your last statement. I will try those things.

BTW i have long suspected something with my PM2 module. In fact from the start when i first purchased my apex. However, neptune just keeps saying nothing is wrong when the readings were bouncing all over. Perhaps it was the Pm2. I will take a closer look and see if something jumps out. do you mind if I pm you with pics for any added assistance on this would be appreciated. Thanks

 

[Ariel V Rosa]

You make alot of good points here that no one suggested. especially your last statement. I will try those things.

BTW i have long suspected something with my PM2 module. In fact from the start when i first purchased my apex. However, neptune just keeps saying nothing is wrong when the readings were bouncing all over. Perhaps it was the Pm2. I will take a closer look and see if something jumps out. do you mind if I pm you with pics for any added assistance on this would be appreciated. Thanks

Anytime, freely PM, Electrical and electronic things are more my expertise. I honestly think Apex is doing too much to look flashy by giving users real time point to point reading instead of using RMS readings. Not even multimeters give instantaneous readings, it all gets ran through RMS to present a reliable number to the user as a pretty reliable point of measure to make decisions with.