Grounding probe caused my pumps to die?

[bubblemytip]

So three days ago, I installed a ‘titanium’ grounding probe on my reef, placing it in my sump.

Within 12 hours, my vectra m1 died. The driver still lights up and a reset didn’t help. A new power supply didn’t solve the issue either. 15-16 months old. Not under warranty. Had had zero issues up till now. Great (!) luckily I had a spare return, an AC Eheim Compact+ 3000.

I thought it was just the vectra having issues as some people have experienced...

However, the next day, my tunze 6040 powerhead died in a similar fashion - controller still receiving power, but the impeller just not turning - motor apparently dead.

This raised my suspicions. I checked the grounding probe and found corrosion/plating. Electrolysis? Pic below.

Has anyone experienced something similar? Or could someone explain the issue? Or is it just coincidence?

Only other things with wires in the tank are a tunze calcium reactor, two eheim heaters controlled by my Apex that haven’t turned on in the last seven days, and the return pump. Not currently running a skimmer.

I have two mp10s that are unaffected. Possibly because their motors are outside the tank.

I have ordered a multimeter to test for stray voltage. But the heaters’ outlets have been off since early last week. Any other ideas welcome.

Thanks!

 

[ksed]

@Brew12

 

[Brew12]

So three days ago, I installed a ‘titanium’ grounding probe on my reef, placing it in my sump.

Within 12 hours, my vectra m1 died. The driver still lights up and a reset didn’t help. A new power supply didn’t solve the issue either. 15-16 months old. Not under warranty. Had had zero issues up till now. Great (!) luckily I had a spare return, an AC Eheim Compact+ 3000.

I thought it was just the vectra having issues as some people have experienced...

However, the next day, my tunze 6040 powerhead died in a similar fashion - controller still receiving power, but the impeller just not turning - motor apparently dead.

This raised my suspicions. I checked the grounding probe and found corrosion/plating. Electrolysis? Pic below.

Has anyone experienced something similar? Or could someone explain the issue? Or is it just coincidence?

Only other things with wires in the tank are a tunze calcium reactor, two eheim heaters controlled by my Apex that haven’t turned on in the last seven days, and the return pump. Not currently running a skimmer.

I have two mp10s that are unaffected. Possibly because their motors are outside the tank.

I have ordered a multimeter to test for stray voltage. But the heaters’ outlets have been off since early last week. Any other ideas welcome.

Thanks!

The ground probe wouldn't cause a problem, but it could be showing indications of other problems.

Do you use a GFCI? Or is your tank close enough to a bathroom/kitchen to run an extension cord to one?

 

[Brew12]

@Brew12

Thanks for the invite!

 

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How old is the home?
I’ve seen some interesting wiring jobs where neutrals were crossed with negatives

 

[bubblemytip]

In New Zealand, all domestic wiring now has to have RCDs (another name for GFCIs, I believe?) and the tank is definitely on an RCD-protected circuit. The house is new, wired in 2015, I believe.

 

[bubblemytip]

The ground probe wouldn't cause a problem, but it could be showing indications of other problems.

Do you use a GFCI? Or is your tank close enough to a bathroom/kitchen to run an extension cord to one?

If the heaters are plugged into the Apex powerbar and not 'on', could they still be leaking current? Just in case, I have unplugged them for now until the multimeter I have ordered arrived. Don't want my backup return pump to fail too before the replacement arrives (Tunze 1073.05 on its way to replace the Vectra M1).

Any other suggestions would be more than welcome.

 

[Brew12]

In New Zealand, all domestic wiring now has to have RCDs (another name for GFCIs, I believe?) and the tank is definitely on an RCD-protected circuit. The house is new, wired in 2015, I believe.

Yup, GFCI's and RCD's are the same thing.

I've never seen a ground probe look like that before. Moderate amounts of current flowing through it may have explained it but that is unlikely in a RCD protect outlet.

Is your ground probe plugged into a power strip or into an outlet?

 

[Brew12]

If the heaters are plugged into the Apex powerbar and not 'on', could they still be leaking current?

In theory, they can if not plugged into outlets 4 and 8 on the older style EB8's. However, if they were, that should trip the RCD.

Don't want my backup return pump to fail too before the replacement arrives (Tunze 1073.05 on its way to replace the Vectra M1).

I'm struggling to see how any of these are related. Unless you have a wiring issue any interaction with the ground probe should cause an RCD trip.

 

[bubblemytip]

In theory, they can if not plugged into outlets 4 and 8 on the older style EB8's. However, if they were, that should trip the RCD.


I'm struggling to see how any of these are related. Unless you have a wiring issue any interaction with the ground probe should cause an RCD trip.

Thanks for the replies. The ground probe was plugged into an outlet on one of my three EB6 (all the outlets are the same on the 220v Apex powerbar). Two of the EB6 share a wall outlet (ground probe and tunze 6040 on one of these), and the third is on a different wall outlet altogether (vectra on this one).

It's got me puzzled too.

 

[bubblemytip]

Multimeter measured 5-6v in the sump and in the display. Is this significant? It did not change when the return pump or calcium reactor pump was switched off. Only other wires in the tank would be from pH/temperature probes and a tunze osmolator float switch.

 

[[Cameron]]

This looks like some stray voltage issue either from the probe itself or some other device. If the multi-meter was set for AC, negative plugged into the wall outlet ground, positive put in the tank and it showed any voltage you most likely have a stray voltage issue. Best to start unplugging items one at a time until the meter stops moving. I would start with the heaters and ground plug itself. It is possible salt creep might be sucking in voltage from outside the tank so check the lights and such as well.

 

[Brew12]

Multimeter measured 5-6v in the sump and in the display. Is this significant? It did not change when the return pump or calcium reactor pump was switched off. Only other wires in the tank would be from pH/temperature probes and a tunze osmolator float switch.

Is this with the ground probe installed, or without?

 

[TheEngineer]

The ground probe was plugged into an outlet on one of my three EB6

This seems problematic to me. Ideally the probe should be plugged directly into your RCD at the wall. If you have a wiring issue in the Apex it could be causing your stray voltage. The oxidation seems strange to me too. When in the water, do you notice bubbles on the probe?

 

[alton]

If you have voltage at your wall receptacle grounding prong your service equipment ground is not good enough or you have a secondary panel which feeds the receptacle that has the grounding and grounded wires on the same bar. Also in reading about RCD's they provide protection but not even close to our GFCI breakers (trip at 5MA). RCD can be from 10-300 MA, similar to our two pole GFCI breakers made for spa's-hot tubs and swimming pools 30 ma which have now been lowered to 6 ma class A.

 

[bubblemytip]

Is this with the ground probe installed, or without?

This was with the ground probe out of the water and being used as the ground for the multimeter.

 

[bubblemytip]

This seems problematic to me. Ideally the probe should be plugged directly into your RCD at the wall. If you have a wiring issue in the Apex it could be causing your stray voltage. The oxidation seems strange to me too. When in the water, do you notice bubbles on the probe?

No bubbles that I could see but maybe a time lapse would pick them up. Not sure.

 

[bubblemytip]

If you have voltage at your wall receptacle grounding prong your service equipment ground is not good enough or you have a secondary panel which feeds the receptacle that has the grounding and grounded wires on the same bar. Also in reading about RCD's they provide protection but not even close to our GFCI breakers (trip at 5MA). RCD can be from 10-300 MA, similar to our two pole GFCI breakers made for spa's-hot tubs and swimming pools 30 ma which have now been lowered to 6 ma class A.

You may be right. I’ll look into getting some RCDs or GFCI plugs with a lower threshold. This is a pic of the RCDs installed. Only have two, as I live in a tiny house.

In terms of the voltage in the tank, what next steps should I take and how to measure etc? Reasonably clueless when it comes to electrical engineering. Studied biology and law

Many thanks for your time so far.

 

[ksfulk]

Is it actual corrosion on the grounding probe, or is it just precipitation? Ive had a vectra just crap out on me, it was a motor block problem, but it was running fine and just died. Im guessing it more coincidental than anything else. I cant think of a way that a grounding probe would cause the pump motors to stop working.

 

[Brew12]

You may be right. I’ll look into getting some RCDs or GFCI plugs with a lower threshold. This is a pic of the RCDs installed. Only have two, as I live in a tiny house.

In terms of the voltage in the tank, what next steps should I take and how to measure etc? Reasonably clueless when it comes to electrical engineering. Studied biology and law

Many thanks for your time so far.

Even though he is correct, I wouldn't worry about changing breakers. We are still talking such small currents that it won't have a meaningful impact.

This is what I would do next. Take an extension cord and run it to an outlet in a different part of the house. Take a voltage reading between the ground on the extension cord and the ground on the EB8. I would also take a voltage reading between the tank and the extension cord ground.

I cant think of a way that a grounding probe would cause the pump motors to stop working.

This is exactly what I am struggling with. A ground probe cannot impact a properly functioning motor. Well, unless you jam it into the impeller. The only way they can interact is if part of the motor winding is exposed to the salt water. The issue with this is that it would trips your RCD immediately.


I like the precipitation thought. Do you have dosing lines that discharge near the ground probe?