Thermal Reckoning, a Fire in the making...

Grey Guy

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Eliminating 120 A.C. Power cords whenever possible is a good idea. Most low voltage transformers will burn out before they burn up. I've been wondering if anyone is working on a D.C. Tank heater, or some kind of power other than 120 A.C. Unfortunately household electgricity can start a fire without ever tripping the breaker. Ironically Thomas Edison said that A.C. Was too dangerous for the household and advocated D.C. Only. Then he has one of the largest A.C. Suppliers named after him. Of course A.C. Was chosen because it was cheaper. How much is a human life really worth?
 

Brew12

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Eliminating 120 A.C. Power cords whenever possible is a good idea. Most low voltage transformers will burn out before they burn up. I've been wondering if anyone is working on a D.C. Tank heater, or some kind of power other than 120 A.C. Unfortunately household electgricity can start a fire without ever tripping the breaker. Ironically Thomas Edison said that A.C. Was too dangerous for the household and advocated D.C. Only. Then he has one of the largest A.C. Suppliers named after him. Of course A.C. Was chosen because it was cheaper. How much is a human life really worth?
Agree with the first part of that statement with trying to go with more low voltage equipment.

AC wasn't chosen because it was cheaper, it was chosen because of transformers. To use DC would have required a power plant every few blocks in a city and rural residents would have needed their own generators or one for every few houses. Transformers allow AC to be sent long distances.
 

Grey Guy

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And you don't think that would have cost more?
 

Brew12

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And you don't think that would have cost more?
At the time, not as much of a difference as you may think. The cities were built with without any infrastructure in place. The capability to build the massive turbines, generators, and transformers hadn't been well developed yet. They didn't have the modern equipment in place to perform miles long cable pulls. Most major cities already had some DC plants in place and sold power, mostly used for arc lighting. It was all about the transformer. In many ways, DC still is more cost effective and now that HVDC has been made reliable enough, it isn't impossible to think of a future where AC is phased out almost entirely.
 

Grey Guy

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O.K. You win. How come you know all this stuff? Just curious, where did you learn it?
 

Brew12

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O.K. You win. How come you know all this stuff? Just curious, where did you learn it?
I used to teach electrical theory and we included lessons on the history of electrical power.
 

Grey Guy

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Awesome. Thanks. It is an honor to chat with you.
 

Turbo's Aquatics

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@Brew12 I was happy to see you post that because I have to regularly correct people when they say "you can't do DC over long distances" and I'm like "hhhrrrump hrrrrump....here let me google that for you"
 

Brew12

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@Brew12 I was happy to see you post that because I have to regularly correct people when they say "you can't do DC over long distances" and I'm like "hhhrrrump hrrrrump....here let me google that for you"
I've had the privilege of working with some of the ABB power rectifier engineers on a project or two. I was doing large scale power factor correction but it isn't too dissimilar. HVDC is really an incredible advancement.
 

Brew12

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Daddy-o

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I ran 2 new dedicated gfci outlets and keep all wiring up on the wall. I do a lot of electrical repairs during the day and the two biggest issues I see are loose screws holding wires and when the wire was stripped, too small of a diameter cut was made on the insulation and the conductor is partially cut/crimped. This will slow down the electricity at this spot and create heat. Much the same as when you kink a hose.
Cheers! Mark
 

Brew12

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This will slow down the electricity at this spot and create heat.
Well, it doesn't actually slow it down, but it does increase the current density and create heat. Excellent advice on what to look for. All connections need to be tight and conductors are sized the way they are for a reason!
 

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Well, it doesn't actually slow it down, but it does increase the current density and create heat. Excellent advice on what to look for. All connections need to be tight and conductors are sized the way they are for a reason!
Okay - not slow down - but density - Thanks!
Cheers! Mark
 

powers2001

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If you look at it from the point of view that it's the only reason you installed the GFCI, you have reduced the likelihood of a flare up, but GFCIs are notorious for tripping easily (as designed) and some hobbyist choose not to incorporate them based on past experiences with the outlet turning off their entire system. I'm all for safety so better that, than risk a fire that threatens the lives of my family. In addition, GFCI protection devices fail at times, leaving the switching contacts closed and allowing the device to continue to provide power without protection and a real reason to test it regularly or habitually.
To avoid GFCIs from tripping and turning off your reef's whole electrical system, get GFCIs that have Automatic Reset. Once the ground fault no longer occurs the outlet resumes "on". I had some GFCIs that didn't have Auto Reset and once they tripped they stayed off. They protected my EB8 from my heaters from grounding out and the heaters would turn off and stay off. Spend the extra money and get decent GFCIs.
 

VelocityTech

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Great write up. I have had this happen.

I don't know why. But i woke up, randomly, 3 a.m Came upstairs to find my entire upstairs COVERED IS THICK SMOKE!

I was previously working on a MP40, and never strapped the power supply back up! And the fitting on my Reactor broke, spraying water ALL UNDER the tank. And as we know salt water, extremely well conductor. The Power Transformer sitting on the floor, smelted, and melted, burning the plastics. Filling the house with smoke!
 

Grey Guy

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To avoid GFCIs from tripping and turning off your reef's whole electrical system, get GFCIs that have Automatic Reset. Once the ground fault no longer occurs the outlet resumes "on". I had some GFCIs that didn't have Auto Reset and once they tripped they stayed off. They protected my EB8 from my heaters from grounding out and the heaters would turn off and stay off. Spend the extra money and get decent GFCIs.
As far as I know, a GFCI may not prevent a fire unless it causes a ground fault. Also, GFCI’s are circuit interrupters and not circuit breakers. A fire can start way before either one trips. I just moved all my electrical above my tank so it won’t get wet.
 

Brew12

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As far as I know, a GFCI may not prevent a fire unless it causes a ground fault. Also, GFCI’s are circuit interrupters and not circuit breakers. A fire can start way before either one trips. I just moved all my electrical above my tank so it won’t get wet.
Very true. Odds are that most electrical faults resulting from saltwater will trip a GFCI due to it creating a ground fault. Many faults, such as internal shorting in a light fixture or pump will not and can generate as much heat as a space heater without tripping the branch supply breaker. GFCI is a tool, it will not save you from poor design and housekeeping.
 

Jon McCutcheon

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hi everyone, i am new to site and am doing lots of research before going big into saltwater aquariums, happened upon this thread(is a bit old but is a point worth mentioning) i currently have a fluval 13.8 as mt starter (3 ,months running, has 2 snowflake clowns, fire shrimp, emerald crab, turbo snail and 5 blueleg hermits) a 120g freshwater and a 55g with condo on top red ear slider tank also a 15g fresh tank(wifes in her office)

one thing i didn't see mentioned here was that in a lot of older homes(35+yrs) alot of the electricians ran multiple outlets and fixed lighting on one line, so if your aquarium is on the last outlet of the line and many things are running the voltage drops causing the items to work harder(use more energy) which also causes heat and deteriorates the wires, so when calculating the wattage consumed by the aquarium you maust also take into account everything else that may be on the same line, our house is 97 years old and was wired by someone not certified i am sure as there was only 5 breakers for the outlets and lights in our 2.5 story house

when we bought our place we already had the 120g and 55g tanks and after tripping the breakers many times started investigating the wiring,(have since had house rewired) were the 2 tanks are i had them wire the top outlet and bottom outlet to seperate 20amp gfci breakers, i then but a 15 amp gfci power strip to each, i have the power strips screwed to wall 3" above bottom of tank with the drip cord clamped to floor, this causes all cords to have a drip loop, cords from above are ran thru a clamp on back of stand(below tank obviously) then back to power strip, cords from in stands i cut a hole at very bottom of back wall to run them up thru another clamp to cause a drip loop, i then have a peice of acrylic that is screwed to wall just above the power strips but wider than them(approx 2') that extends from wall approx 5" then goes down approx 5" to help protect against display tank splashing from excited fish or water changes also from unexpected future leaks

sorry for long post but again is a very worth while topic for all to read
 

jasonrusso

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Very true. Odds are that most electrical faults resulting from saltwater will trip a GFCI due to it creating a ground fault. Many faults, such as internal shorting in a light fixture or pump will not and can generate as much heat as a space heater without tripping the branch supply breaker. GFCI is a tool, it will not save you from poor design and housekeeping.
Isn't that why the require arc fault breakers now?
 

Brew12

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Isn't that why the require arc fault breakers now?
AFCI breakers do help with this. If there is arcing involved it should detect it and clear the fault. Right now, a combination of GFCI/AFCI is the best we can do, but we still need to properly maintain and design everything.
 

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