cliff Posted February 26, 2016 Share Posted February 26, 2016 I got curious and hooked up my volt meter to my tank. I'm getting 40 volts in the water. So. I thought I had a bad device. I unplug and re plug one device at a time. And none of them change the voltage more than 1 volt. But...when I turn off the power strip I get 0 volts in the water. I am so confused.... Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 pick up a grounding rod for a tank. a combination of those is causing it most likely. Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 http://amzn.com/B0002DGSWE Link to comment Share on other sites More sharing options...
Juiceman Posted February 26, 2016 Share Posted February 26, 2016 Could also be the powerstrip itself? Is it a good quality strip? Link to comment Share on other sites More sharing options...
jestep Posted February 26, 2016 Share Posted February 26, 2016 It's voltage being induced in the tank due to current flowing through pumps, heaters, anything else in the water. Basically the same effect as a transformer. I've seen anywhere from a few volts to 50 or so. There's a ton of factors that influence how much voltage is induced in the tank, even the quality of wiring in the house can change it, but as long as you aren't reading line voltage (110/120) or aren't reading DC voltage from shorted DC equipment, it's probably not a problem. Read up on grounding rods before doing it. They're to protect people, not fish or coral from shorted equipment. RIght now, there's no path to ground in the tank so there's not actually any current flow. Once you add a grounding probe, the current can flow in the tank and can damage fish and coral. The other problem with them is that if you do short something in the tank, the grounding probe is made to cause your GFCI outlet to trip. The caveat with this, is that if you're not around to catch it, you can lose your tank. Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 when you tested water voltage, what did you ground the negative probe to? have you tried an alternate ground to make sure the initial ground point wasnt the issue, and not the tank? Link to comment Share on other sites More sharing options...
Christyef Posted February 26, 2016 Share Posted February 26, 2016 Voltage? I'm new to the hobby and reading about voltage in a tank is new to me. Can someone explain what this means or point me to a link to read on it? Thnx Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
jestep Posted February 26, 2016 Share Posted February 26, 2016 Voltage? I'm new to the hobby and reading about voltage in a tank is new to me. Can someone explain what this means or point me to a link to read on it? Thnx Sent from my iPhone using Tapatalk Basically any time you have current flowing through a conductor, it will induce (essentially transfer) voltage to another conductor that is in close proximity. This is how certain cordless battery chargers work for electric toothbrushes and cellphones. It's how transformers work as well, much more complicated though. Saltwater is a very good conductor, so our pumps and heaters sitting in the tank or sump will cause voltage to be read when measuring the water with these pieces of equipment running in it. Most tanks measure 10 - 20v, but due to various factors that can increase the overall current through our equipment, some tanks see much more than this. Voltage by itself doesn't actually mean anything. You can measure your electrical outlet or a battery and get a voltage measurement but nothing is connected to it, so no current is flowing. Current is what actually causes damage to people any anything in the path of it. It gets really technical beyond this, but this is essentially why we can measure voltage in a tank. As to the effects, it gets subjective at this point as well. Some people think that any measured voltage is a bad thing and can cause HLLE and other problems. Personally I think it's fine as long as there isn't a path to ground. Basically as long as current can't flow it's irrelevant. Link to comment Share on other sites More sharing options...
Christyef Posted February 26, 2016 Share Posted February 26, 2016 So, some voltage is ok and basically expected? I've never tested for that. I'll look into it. I lost 4 fish suddenly a couple days ago and haven't been able to pinpoint why. Looking at every angle to keep it from happening again Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
jestep Posted February 26, 2016 Share Posted February 26, 2016 So, some voltage is ok and basically expected? I've never tested for that. I'll look into it. I lost 4 fish suddenly a couple days ago and haven't been able to pinpoint why. Looking at every angle to keep it from happening again Sent from my iPhone using Tapatalk If you have a multimeter, just test from the tank to a ground hole on an electrical outlet on the AC volts setting. I'd test the outlet first just to be sure the ground works though, test from the smaller slot on the outlet to the ground hole, it should read ~110. As far as the tank goes, it's bad if you measure full 110 line voltage in the tank, this means that something is actually shorted in the tank. It's also dangerous to a human if you don't have the tank on a GFCI outlet. You can get severely shocked if this is happening, but if you're wearing shoes or are on carpet whenever you touch the water, you may still never know there's a short. Anything but line voltage is induced voltage. You can't have a partial short, it's either full line voltage or none, as far as shorts go. Link to comment Share on other sites More sharing options...
Christyef Posted February 26, 2016 Share Posted February 26, 2016 I actually do have one of those. I'll do that this evening. Thank u so much for your knowledge [emoji5] Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
cliff Posted February 26, 2016 Author Share Posted February 26, 2016 I used an extension cord plugged into another outlet on a different circuit. I put the black prong into the negative. And the red into the tank. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
cliff Posted February 26, 2016 Author Share Posted February 26, 2016 And I am going to buy a better power strip today. A metal one. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
cliff Posted February 26, 2016 Author Share Posted February 26, 2016 I am also going to get a gfi. I would much rather my tank die than my wife. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 the capacitive "radiation" should be negligible, if you are reading it, something is off, one of your pumps needs cleaning (increased friction causes this) or you may actually have stray voltage from a damaged device/cord. if you do decide to ground the sump, put it as close to the source as possible. the farther away it is, the more items in between the flow, and more issues you will have, as jestep alluded to. grounding the sump properly isnt bad, especially if you have other equipment which is wet and possibly conductive to another ground source. Plus, if you have a GFCI on the system, it has an allowable tolerance for this kinda thing, once its outside those tolerances, it will trip. if you have it on gfci, i wouldnt worry about it too much, until it starts tripping often. Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 jestep made me do a sanity check. 0.4v in a small cup which my ATO dispenses into which i put my buffer in. all plastic, no conductive elements (ie.. baseline, you can subtract this from all other readings. most meters are +/- 0.3-0.5v if i recall.) 1.1v in the pump area of my sump which has an old rio 1100 for my calc reactor and nitrate coil and jeabo dc-9000 0.8v in the other side of the sump by the skimmer feed pump 1.7v in the CARX effluent box. only thing that is conducting to is the CARX chamber, thus that recirc pump and THAT feed pump. you at 40v, theres some stray current somewhere. move the meter probe around, zero in on the area, turn off that pump, check again. Since they are off, clean em If you still cant find them, try a diff meter! harbor fright gives em away for free. I usually use one of those as a sanity check if i think something is amiss on my meter. Link to comment Share on other sites More sharing options...
Isaac Posted February 26, 2016 Share Posted February 26, 2016 it should read ~110. Should be in the 120-128 range in texas. I think the nema specs are actually 110-130. This is what my UPS says: High Line Voltage Max 126.00 V AC, Avg 124.61 V AC, Last 123.03 V AC Low Line Voltage Max 124.00 V AC, Avg 122.41 V AC, Last 122.01 V AC Link to comment Share on other sites More sharing options...
cliff Posted February 27, 2016 Author Share Posted February 27, 2016 I checked the voltage in the tank. One at a time I unplugged every single thing in my tank. The return pump, power head, heater 1, heater 2, tank light, refugium light. Everything. Nothing dropped it more than a volt. Turn off the power strip. 0. In my mind. I have hypothetically ruled out a bad device. I'm not electrician. But I am pretty sure if it's a bad device it should drop the voltage in the tank when I unplug it.... I just made a batch of water. Put a slpower head in the bucket ( not one that was in my tank ) just for grins, I tested the water. 30 volts. Went to my wife's tank. Checked hers. She only has a heater and a HOB filter. 30 volts. It's got to be residual. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
jestep Posted February 27, 2016 Share Posted February 27, 2016 At this point, I'd get someone with a different meter measure it, preferably a fluke or other professional quality meter. Also, test a power outlet in your house and make sure it reads correctly. Link to comment Share on other sites More sharing options...
Christyef Posted February 28, 2016 Share Posted February 28, 2016 Cholder777, some voltage is to be expected..... From what I've been told Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
cliff Posted February 28, 2016 Author Share Posted February 28, 2016 I checked the outlet. It's good. 120 ground to hot. 0 neutral to ground. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
cliff Posted February 29, 2016 Author Share Posted February 29, 2016 Ok. I called my dad who is a master electrician 35+ years. He came by and tested it. Same 40 volts... Fish dont seem to care. Im going to replace the powerstrip and if that doesn't fix it i'm just going to let it ride and see how things turn out. Im stumped..... Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.