Aquarium and electrical safety

[Paul B]

i just heard about Miami here on this thread and i feed really bad. i had many conversations with him.

The 50 volts came from leaking powerheads so that would be stray voltage.

i dont want to get into ground probes, electric eels and all that because i am an
"A" rated, master construction electrican and disagree with much of the forum electricity talk. but i will say that all electricity leaking from a heater, light or other appliance touching the water will be line voltage over 110 volts

lower voltages are just induced and for the most part inconsequential.

sorry about the typing. i had my right shoulder replaced a few days ago

 

[exnisstech]

i just heard about Miami here on this thread and i feed really bad. i had many conversations with him.


i dont want to get into ground probes, electric eels and all that because i am an
"A" rated, master construction electrican and disagree with much of the forum electricity talk. but i will say that all electricity leaking from a heater, light or other appliance touching the water will be line voltage over 110 volts

lower voltages are just induced and for the most part inconsequential.

sorry about the typing. i had my right shoulder replaced a few days ago

Thanks Paul. Hope you heal quickly.

 

[BeanAnimal]

Hey all. Great post. Can someone chime in with the real story on these devices? I am not interested in the debate about stray voltage and inhabitants. I am much more concerned if this helps with HUMAN safety:

The ground probe provides a current path to ground. When used with GFCI protection, the device will trip if there is a fault.

Used without GFCI protection, you create (in theory and in practice) a danger that did not otherwise exist.

Let me briefly explain five variations of the same scenario.
Scenario:
You have a light fixture over the aquarium that has faulted. The metal case of the fixture is "hot" because somewhere inside of the fixture, the hot wire is touching the metal enclosure. The light happily chugs along without tripping the breaker.

You reach into the tank to do some work, your ear (or shoulder) or whatever touched the metal fixture.

1 - NO GFCI and NO GROUND PROBE. You are wearing rubber soled shoes.
In theory, no current flows. There is no path through your body to lower potential even though your hand is in the tank and your ear or shoulder touching something energized by a fault. The situation is still very dangerous, but the tank and your body have no path to ground.

2 - NO GFCI but there IS A GROUND PROBE. You are wearing rubber soled shoes.
In theory and practice you are going to get shocked. Current will travel from the fixture through your ear (or shoulder), then through your wet hand and out through the ground probe. YOU become the connecting wire.

3 - GFCI protection with A GROUND PROBE. You are wearing rubber soled shoes.
In theory and in practice you are going to get a minor shock that you may or may not feel. The moment that your body becomes the "wire" the GFCI will sense the fault and trip, saving your life.

4 - GFCI protection WITH or WITHOUT A GROUND PROBE. You are barefoot. Same protection as #3. The moment that your body completes the circuit, the GFCI trips to protect you.

5 - NO GFCI and NO GROUND PROBE and you are barefoot. You don't need to touch the tank, the moment you touch the fixture, you get shocked!

 

[Shinji Ayanami]

Had a small incident 3 weeks ago where a pump died. Was holding it and reached for the light switch.

Thankfully here in Aus our regulations mean that every power circuit is on an RCD safety switch.

I also use Safety Switch boards as an extra bonus - the one that always catches me though is the water change station.
Pumps getting moved in and out of tanks and drums, the cables get weak around the connection points and start to break.

I think that’s what happened to my Reef Casa pump about 3 weeks ago. I came home to my ATO high-water alarm, which usually means the return pump is off since there was no water on the floor. I reached in and grabbed the pump and gave it a few smacks thinking it was gummed up.

After a few minutes of heavy-handed troubleshooting, I went to reach up and turn on the fan light and got a nice little surprise. Nothing major, but the arm holding the pump was definitely energized I was able to drop the other hand off the light and yank the plug from the wall.

That’s now the second time I’ve gotten shocked working on a tank one freshwater, and now one salt. Both times I just brushed it off, but I’m realizing now that was probably a mistake. Any number of tiny differences and I could’ve gotten more than just a tickle.

So is the standard now just to shut everything off before putting your hands in the tank?

All three of my tanks run on a Geeni smart plug strip and are connected to a standard 120V American home outlet pretty sure they’re all on the same circuit.

 

[Paul B]

just for information, gfcis are designed to be "fail safe" which means they fail in the safe position, or off.

thats the plan anyway

 

[Reefer Matt]

Here’s a video I made on this topic a couple years ago that almost no one watched. I tried to illustrate the proper configuration for using a gfci and ground probe.

 

[vetteguy53081]

Wow! This has been a horrible week. First loosing my dog and now after taking a few day break from here R2R only to return and find out the tragedy my friend Baruch/ @Miami Reef has been lost . Seems he has passed from an electrical incident while working in his tank. Unsure how this has happened!?!? He just had an electrician over several months ago to fix some issues and correct them. Regardless I think it’s important to discuss proper electrical safety with our glass boxes. At most maybe we can help prevent this from happening to someone else!

I’m am not a licensed electrician but am familiar with electricity. I’ve wired sub panels in for my tank amongst several other electrical projects.

**** A MUST FOR ANY TANK***

Please ensure your tank equipment is on a GFCI circuit! Weather it be an outlet or breaker in the panel. Our tanks must be installed on either! Safety, fire hazard, etc!

A standard GFCI outlet

Your equipment should be plugged into an outlet like this! It’s possible the circuit your tanks on has one further up the branch. These work by tripping the outlet and anything further down the circuit branch will be without power until it’s reset and the fault is corrected.

Another option is installing a GFCI breaker in the electrical panel. This option ensures the entire electrical circuit is protected by GFCI

(Photo from my subpanel in basement. The 20amp GFCI/arc fault breaker with the purple test button is my dedicated fish circuit for everything in the basement)

Even with a GFCI outlets they can wear out and fail! Luckily for $15 you buy a GFCI tester at your box stores or amazon. I recommend purchasing one and testing your GFCI circuits for proper operation.

To add onto the essentials of GFCI protections there’s several other things to take into considerations. Outlets that aren’t in use I like to install child proof plugs to help somewhat with moisture possibly. Might not do much but can’t hurt.

Other things to consider though much debate on though is grounding rods installed in your tank. A titanium heater with a 3 prong outlet can double as a grounding rod.

Between cord management and safe electrical set ups there’s many things we should all review and correct. Let’s let this be a lesson and hopefully learn from it so it doesn’t happen to someone else. If you’re unsure and not comfortable with electricity I’d recommend calling out an electrician to review your set up and insure it’s GFCI protected. If not, while over have them install one.

Feel free to add/correct anything I’ve mentioned. I just don’t want to see anything like this happen again. So let’s educate everyone on this subject to ensure we’re all safe in our tanks. Sorry I’m not the greatest at writing things like this but just trying my best to come to terms with loosing my friend.

RIP brother @Miami Reef

A clear reminder that water and electricity do not mix and outcomes are never positive. Ive seen GFCI fail but rarely and if in doubt, always worth the expense of a licensed electrician.

 

[Tangdora]

Yes BRS titanium heaters act as grounding probe. Any titanium heater with a 3 prong plug.

Still have probes in the box that I never setup, time to find. But the titanium heaters completely slipped my mind. Have 3 currently down in my sump (on gfci only) so sump is good but don’t if they should be relied on as the primary source for a whole tank with sump unless you plan to keep one in each area. Given the only direct path to the main tank is thought the return. When maintenance is being done returns are typically off thus creating two independant water sources. Would still wise to have a dedicated probe still in the display if planning to use one.

 

[jonelder68]

Still have probes in the box that I never setup, time to find. But the titanium heaters completely slipped my mind. Have 3 currently down in my sump (on gfci only) so sump is good but don’t if they should be relied on as the primary source for a whole tank with sump unless you plan to keep one in each area. Given the only direct path to the main tank is thought the return. When maintenance is being done returns are typically off thus creating two independant water sources. Would still wise to have a dedicated probe still in the display if planning to use one.

Good point!

 

[mcarroll]

GFCI

Most experts I know will not use GFCI's on tanks because they tend to trip for no reason when folks are away and then the whole tank is killed.

Can you (or someone) talk about why this happens and how it can be avoided?

(I know a little about why, but not enough to explain it. It's important and usually gets glossed over along with the stray voltage issue, so if someone in the know could address both it would be great.)

 

[mcarroll]

The ground probe provides a current path to ground. When used with GFCI protection, the device will trip if there is a fault.

Used without GFCI protection, you create (in theory and in practice) a danger that did not otherwise exist.

Let me briefly explain five variations of the same scenario.
Scenario:
You have a light fixture over the aquarium that has faulted. The metal case of the fixture is "hot" because somewhere inside of the fixture, the hot wire is touching the metal enclosure. The light happily chugs along without tripping the breaker.

You reach into the tank to do some work, your ear (or shoulder) or whatever touched the metal fixture.

1 - NO GFCI and NO GROUND PROBE. You are wearing rubber soled shoes.
In theory, no current flows. There is no path through your body to lower potential even though your hand is in the tank and your ear or shoulder touching something energized by a fault. The situation is still very dangerous, but the tank and your body have no path to ground.

2 - NO GFCI but there IS A GROUND PROBE. You are wearing rubber soled shoes.
In theory and practice you are going to get shocked. Current will travel from the fixture through your ear (or shoulder), then through your wet hand and out through the ground probe. YOU become the connecting wire.

3 - GFCI protection with A GROUND PROBE. You are wearing rubber soled shoes.
In theory and in practice you are going to get a minor shock that you may or may not feel. The moment that your body becomes the "wire" the GFCI will sense the fault and trip, saving your life.

4 - GFCI protection WITH or WITHOUT A GROUND PROBE. You are barefoot. Same protection as #3. The moment that your body completes the circuit, the GFCI trips to protect you.

5 - NO GFCI and NO GROUND PROBE and you are barefoot. You don't need to touch the tank, the moment you touch the fixture, you get shocked!

Thanks for hitting question of the grounding probe!


Now if someone can explain the "false positive" shutoffs that GFCI's are subject to....

 

[jonelder68]

Thanks for hitting question of the grounding probe!


Now if someone can explain the "false positive" shutoffs that GFCI's are subject to....

Bean could probably explain better than I could attempt. But honestly I’ve had no issues with fails trips so far with my GFCI/AFCI combo breakers. Ideally you also have two separate circuits incase of this. That way one is still providing oxygen/gas exchange.

I will say GFCI outlets like everything have an expiration date. When I first bought my house 12 years ago my bathroom GFCI wall outlet would trip frequently. Replaced the outlet and hadn’t had anymore issues for years. The bathroom has since been gutted and completely remodeled now and is on GFCI/AFCI combo breakers.

The GFCI tester tools are also great for checking GFCI issues. I recommend getting one and testing outlets & breakers at least annually.

 

[mcarroll]

Most of the time you need a plugin GFI to plug into ordinary househoold outlets....so that's mostly what I'm referring to.

Like this:

Seems like any blip in the AC-side supply would cause it to pop. In businesses it seems worse, but unreliable.

 

[jonelder68]

Most of the time you need a plugin GFI to plug into ordinary househoold outlets....so that's mostly what I'm referring to.

Like this:

Seems like any blip in the AC-side supply would cause it to pop. In businesses it seems worse, but unreliable.

Ya I have no experience with those. I’d always recommend having a breaker or proper outlet installed. I don’t know the pricing as it would be different across the country but surely for a few $100 or so an electrician would install either. If you’re not comfortable/knowledgeable to do it yourself. A few hundred dollars for safety is a small fee in my opinion.

 

[mcarroll]

I think the phenomenon is called "nuisance tripping" and it seems the general recommendation is not to plug life-support devices into GFCI outlets.

Is avoiding GFCI/AFCI the most correct answer or is there an actual workaround?

 

[zbrusko]

Leave the probes in the spots that they are in.
Turn the dial to to the red setting at 5:30 that has the diode symbol (triangle with line) and speaker (sound) symbol.

Touch the probes together. You should hear a tone. The display will show 0 or (or close). This means continuity (an electrical connection).

Now do the same with the heater. Touch one probe to the center pin of the plug and the other to the heater's body. If you hear a tone, then there is a connection.

Great, thank you!

 

[don.chaneaux]

Having no true knowledge of electricity, would testing the water with a multimeter be beneficial before reaching into the tank? What test settings should be used?

Granted this will not prevent any issues while working inside the tank (splashes, equipment failures, etc) but might help in some cases.

 

[BeanAnimal]

Can you (or someone) talk about why this happens and how it can be avoided?

A GFCI compares the current flowing out on the hot conductor to the current returning on the neutral. Any difference means current is leaking somewhere else. So, possibly through you or water, and it trips.

UL 943 specifies that a GFCI must trip when the imbalance is between 4 mA and 6 mA.

Such leaks are called faults and may result from real insulation faults. They may also not be actual faults, but rather small capacitive or inductive leakage inherent to normal devices.

If a single device is connected, it can leak up to about 4 mA before tripping. Large transformers (think MH ballasts), capacitors (LED power supplies), or motors (pumps) with poor power factor can cause brief transient imbalances when energized.

When many aquarium devices share one GFCI, each may leak a small amount (often < 1 mA) of current. This is normal and expected. However putting say, ten devices on a single GFCI might total 3.5 mA of normal leakage. A short inrush event adding just 2 mA raises the total to 5.5 mA, exceeding the trip threshold.

Most homes have GFCI breakers or a single GFCI receptacle fed from a standard breaker. The single GFCI breaker or receptacle feeds multiple outlets resulting in “downstream” protection. This makes nuisance trips common for complex systems like our aquariums where we cram pieces of equipment onto a single GFCI. The better approach is to have an electrician install multiple GFCI receptacles or circuits so equipment groups are isolated. That limits nuisance trips and keeps critical gear running when another branch trips.

Extension cord and plug-in type GFCI adaptors are often more prone t nuisance tripping. They are typically set to the lower end of UL 943 (closer to 4 mA) and often often more sensitive (not a bad thing) to transients than dedicated NEC approved devices. Also many "trip" when unplugged to prevent a power tool from coming back on after a power failure.

 

[BeanAnimal]

Having no true knowledge of electricity, would testing the water with a multimeter be beneficial before reaching into the tank? What test settings should be used?

Granted this will not prevent any issues while working inside the tank (splashes, equipment failures, etc) but might help in some cases.

Not for most people. The readings are ambiguous in most cases. The proper thing to do is properly utilize GFCI protection with ground probes.

 

[BZOFIQ]

Most experts I know will not use GFCI's on tanks because they tend to trip for no reason when folks are away and then the whole tank is killed.

Can you (or someone) talk about why this happens and how it can be avoided?

(I know a little about why, but not enough to explain it. It's important and usually gets glossed over along with the stray voltage issue, so if someone in the know could address both it would be great.)

You can get around it by either installing multiple circuits or splitting a single circuit into multiple GFCI outlets (not inline). If One trips the others will continue working.

Here is one way.

Additionally, you can monitor for tripped outlets using your controller.