Voltage drops by half under load??

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Old 04-09-17, 06:44 PM
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Voltage drops by half under load??

I bought. Kasco 4400vfx display aerator for HOA pond. There was already an electrical receptacle near the bank to which a low voltage landscape light transformer was attached, so I figured I was set on the power source. Even installed a conduit direct from the waterline to near the receptacle for easy install.

Plugged the fountain in and it barely functions. Puny display. Then the LED lights failed. Then the fountain switched off after about 15 minutes.

So I tested the voltage with a multimeter. Reads 120v as it should. No difference when I plug in the LED transformer. The minute I plug in the fountain, HUGE voltage drop by almost exactly 50%!

The fountain is 120v and 11.3 amps. I actually pulled the fountain to verify the specs printed on the pump. It's basically a hair dryer in terms of load.

I also inspected the power cord, which was supplied by Kasco for the fountain specifically for this fountain and for underwater use. No kinks or damage that I can see. Fountain is brand new.

What do you think the problem might be? Something with the power source or is it a problem with the pump? What should I test? I am NOT an electrician.

Thanks!!
 
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Old 04-09-17, 07:04 PM
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Plug something with similar power requirements (that hair dryer would probably work) into the same receptacle and see if the voltage drops in the same way. If so, you know the problem is on shore. If not, you know the problem is with the fountain.

You could also plug the fountain into a known good receptacle to see if it works (but just for a few seconds as it won't be in water).
 
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Old 04-09-17, 07:21 PM
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How long is the supply line to the receptacle ?
With long distances.... voltage drop increases rapidly with high current loads.
 
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Old 04-09-17, 07:29 PM
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Odds are that the run to the outlet from the main panel is undersized. Not as big a deal with a puny little transformer for the LEDs, but then you put a heavy load on (75% of max on a 15amp circuit, 56% on a 20amp circuit) and the voltage drops drastically. Same as you could run a 100W worklight on a 100 ft 16 gauge extension cord, but trying to run a circular saw would probably burn the motor out.

The pump probably shut off due to a thermal overload. If you reduced the voltage by half, then the amps doubled. You're probably on a 20 amp circuit or the breaker would have tripped.

Find the breaker and whatever else it attached to that run, then look at (or get someone to look at) the gauge of connected wire. Then measure the distance from the breaker to the outlet. With those numbers I'll bet the Pro's tell you it's undersized wire feeding the outlet for that large a load.
 
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Old 04-09-17, 08:17 PM
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So.... you're saying if the receptacle is 600 feet from the breaker that might be the problem? Crap! I'm seeing a lot of dollar signs.

So what are my options here? Either run a new heavier gauge line all the way from the existing breaker (I'm sweating just thinking how expensive that'd be) or somehow install a new breaker close by? We have houses with backyards less than 50 feet from the shore so there gotta be some high voltage line much closer than the current breaker. Thoughts?
 
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Old 04-09-17, 08:21 PM
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the receptacle is 600 feet from the breaker
That distance is a major problem. Assuming #14 wire with a ~12 amp load your voltage drop is ~45 volt, about 38%. What is the actual wire size feeding it? You would need #6 copper or #4 aluminum wire to even get close to having enough current (5.9% voltage drop). To meet the often recommended sweet spot of 3% even larger wire. Probably need to consider aluminum mobile home cable or having a meter installed.

Note the breaker needs to be 20 amps given the amperage of the fountain.
 

Last edited by ray2047; 04-09-17 at 08:47 PM.
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Old 04-09-17, 08:45 PM
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Darn. Im guessing installing a new meter is going to be the best option, and I'm guessing that's still gonna cost a pretty penny. Uggg.
 
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Old 04-09-17, 08:52 PM
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To be clear I meant a meter at the fountain. You may be able to mount a combo meter and breaker box on an architectural feature nearby such as the back of a sign. Are there electric company lines overhead near by or are they buried in backyards? If the latter that could mean trenching through someone's lawn.
 
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Old 04-09-17, 08:56 PM
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The normal rule is only one service to a property.
 
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Old 04-10-17, 05:46 AM
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I would ask my local inspect if he/she would allow a 480V feed. This would not be allowed inside the home, but MIGHT be allowed outside. UF is rated at 600V, but I personally would not do this with a non-conduit feeder. You would need a 4:1 transformer at each end.
 
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Old 04-10-17, 06:07 AM
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The normal rule is only one service to a property
But is this an isolated outdoor area not connected to other common areas. Maybe an esplanade at an entrance. I was visualizing the fountain at the entrance to the subdivision.
 
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Old 04-10-17, 06:14 AM
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I would ask my local inspect if he/she would allow a 480V feed
If the current feed is #12 that might work without running new wire. I get less than a 6% drop at 480 but the calculator I used only does 3 phase at 480. I'm not how that affects the reading. (113 volt after step down if I got my math right.)
 
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Old 04-10-17, 06:35 AM
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Learn about "voltage drop". Search google.com for those terms.

Also search for voltage drop calculator. With that, you can plug in various wires types and sizes and see what happens.

Be aware that due to voltage drop, the electric company boosts the voltage higher - this will travel over long distances with much less of a voltage drop. Then they switch the voltage down at the point it where it will be used (house, building).

With that said, you can get your own transformer pairs which will accomplish the same results. Ask at an electrician's supply (where electricians shop). Or ask an electrician - one which does commercial work.

Another option is for the electric company to install a separate meter at that location, then they would take care of the transformers.

And of course using larger gauge wire.
 
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Old 04-10-17, 07:02 AM
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Here is a map of the area. I labeled the location of the outlet and the breaker. The breaker is attached to the back of a stone column in a hedge row and I'm pretty sure there is a meter there, too.

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So basically, you can see that this is a neighborhood pond. There are a lot of houses nearby. There's also a pool house with a meter there that might be marginally closer to the outlet, but not much. No overhead power lines - it's all buried in the neighborhood.

I don't know exactly how the wire runs from the outlet to the meter, but I expect it runs along the ponds and feeds several other outlets along the way (there are numerous outlets along the ponds where we have transformers plugged in for our extensive LED lighting system). I'm guesstimating a 200 yard run to the meter if it follows the ponds before crossing under the street somewhere.

I don't think it would be hard to add an additional meter closer to the fountain (our neighborhood already has 7 or 8 meters throughout to run things like the pool, wells, irrigation, lights, etc.) - I expect there is heavy high voltage line running along the backyards - but it would obviously be quite costly to install a new meter.

This is a neighborhood fountain, so simply running it off a neighbor's meter isn't an option.
 
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Old 04-10-17, 07:13 AM
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I expect it runs along the ponds and feeds several other outlets along the way (there are numerous outlets along the ponds where we have transformers plugged in for our extensive LED lighting system).
Given the fountain draws 12 amps it needs to be on a 20 amp circuit which wouldn't give much to spare for any other loads. Really needs to be on a dedicated circuit.
I expect there is heavy high voltage line running along the backyards
You need to ask for an engineer from your electric power company to look at the situation and tell you the best/cheapest way they can provide power.
 
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Old 04-10-17, 07:28 AM
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Ok, but assuming it was a dedicated 20amp circuit, what wire would be needed to make it 600 feet? I'm confused as to how voltage, amperage at the source, amperage consumption of the tool, and awg of the wire all relate.

I know voltage drops over the length of the wire due to resistance, heavier awg means less resistance and less drop, but why does my multimeter still say I'm getting 120v all the way at the outlet - until I plug in the fountain and the voltage plummets? The heavy amps needed by the fountain obviously come into play.

By the way, total distance is actually closer to 700 feet because of the fountain's 12awg power cord. I was thinking of testing the fountain by buying a 12awg extension cord, which would be enough to connect the fountain's cord to my backyard external outlet, but that outlet is on a 15amp breaker. Would it work?
 
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Old 04-10-17, 08:08 AM
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Because current (amps) is also a contributing factor in the voltage drop equation. Remember resistance is the opposition to the flow of current through the wire -- resistance plays no part until there is a current to resist. When the current is very low (e.g. only your meter leads), then there is undetectable voltage drop. As soon as you put any significant current on the line the voltage drops correspondingly.

What you're asking is virtually impossible to do at 120V. You would need #2/0 aluminum cable to attain a 3% voltage drop which is roughly $2/ft. Switching to a 240V pump is a necessity. That brings you to only needing #6 aluminum conductors, and you should be able to pick up a 1000' roll of 6/3 aluminum URD cable for somewhere around $650-700 and have a ton of cable left over to resell. Maybe you can find a distributor locally that will let you buy only the part of the roll you need, even better deal. That's a pretty good solution for a run of this length.
 
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Old 04-10-17, 09:50 AM
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It would be a huge pain and added expense, but I could potentially exchange the pump for a less powerful 3/4hp model running on 4 amps at 230 volts. I'd prefer to keep what I've got, but the estimate from the electrician could change my mind.

What a horrible expensive mess I've made. Frustrating that it is so difficult to get adequate power to a spot so close to so many homes. Maybe the electrician will have better news for me, but it's not sounding good.
 
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Old 04-12-17, 08:42 AM
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I met with an electrician and he confirmed the voltage drop problem. He said it would be less expensive to install a new meter closer to the pond bank and confirmed that there is an electric easement with those big green transformer boxes along the backyards only 50 feet west of the pond. Then a short trench from there to install an outlet about 10 feet from the bank.

He said this would be more economical than running a new 240v circuit from the existing meter, not to mention having to replace the pump with a 240v version.

I guess the meter itself is rented from the utility for maybe $12 a month. Any guesses on approximately what it should cost for electrician to install the meter, a breaker box (I assume) and 40' trenched wire to a new outlet?

I'm bracing myself for the bids!
 
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Old 04-12-17, 10:17 AM
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It is impossible to guess local prices but you are probably looking at more than a couple of thousand dollars.
Then a short trench from there to install an outlet about 10 feet from the bank
You will also need a breaker box but he may have meant a combined meter and breaker box.

there are numerous outlets along the ponds where we have transformers plugged in for our extensive LED lighting system
You need to verify the voltage drop at night the lights are on. These receptacles may be getting low voltage which could decrease their life span. You may need to consider supplying some of these from the new breaker panel if it is closer.
 
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Old 04-12-17, 12:51 PM
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Originally Posted by ipbooks
What you're asking is virtually impossible to do at 120V.
...
Switching to a 240V pump is a necessity.
The fountain & pump are 600' from the receptacle.

Uh, perhaps we're focused on the wrong end of the problem?
Would the water pressure drop for a large 600' hose be less than the voltage drop over 600'?

Curious, what about a submersible 240v agricultural irrigation pump near a shore outlet,
and 600' of irrigation hose or used fire hose along the bottom of the pond,
supplying the fountain?
 
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Old 04-13-17, 07:45 AM
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Not THAT is thinking outside the box - good idea!

(Forget about the wiring and instead place the pump at the house and run pipes to the location!)
 
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Old 04-13-17, 08:19 AM
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Pipe friction loss and additional head on the pump will have a similar effect on overall system performance as will voltage drop in the wiring. Physics doesn't give you anything for free.

It sounds like the onsite electrician's plan to install a new meter base in the power company right-of-way near the pond is going to be by far the best option. This is going to be the lowest materials and labor cost of any of the options as long as the power company and local government have reasonable meter tap and permit fees.
 
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Old 04-13-17, 08:52 AM
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Best option appears to be the meter, but it'll come down to cost.

A far less expensive option would be to just run the fountain off my house electric, which backs to the pond and I think could be suitably accomplished with 1 100' 12awg extension cord. I think a 15amp circuit would support that. Looks like it would result in voltage drop of about 7%.

But then of course I'd be billed personally about $75 a month in electric usage for an HOA fountain. Given that I am responsible for getting Board approval for the purchasing and installing the fountain without understanding the added expense of installing a meter, I'm going to go this route until I get approval for the meter.
 
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Old 04-13-17, 09:00 AM
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Can you hide a solar panel close to the pond to run the pump?
 
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Old 04-13-17, 09:30 AM
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I doubt solar is a suitable option. We want to run about 16 hours a day, well into the evening. Would take such a big battery and array to reliably power it that I expect the break even point as compared to installing a meter would be waaaay too far out.
 
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Old 04-13-17, 09:52 AM
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think could be suitably accomplished with 1 100' 12awg extension cord.
That would be a code violation. Extension cords or for temporary use only.
 
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Old 04-13-17, 02:12 PM
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Is there a definition of "temporary" in the code? As I said, I don't intend for this to be a long term solution.
 
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Old 04-13-17, 06:21 PM
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Oh I get what you were saying. Yeah, this would only be temporary.
 
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Old 04-14-17, 01:15 PM
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Fountain is running with the 100' 12/3 extension cord to my house. It is glorious, especially illuminated at night. I haven't checked voltage drop, but it ran 5 hours last night and then fired up again this morning on the supplied timer. I know I need a more permanent solution so I'm keeping fingers crossed for the bids.
 
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Old 04-14-17, 02:41 PM
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Temporary is considered 90 days or less.
 
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Old 04-14-17, 05:17 PM
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This fountain seams like a neighborhood/association item, are you sure you want to be paying to run this thing? 1500 watts (12 amps) running for 16 hrs a day x 30 days @ .15 per KWH = $108 a month.
 
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Old 04-15-17, 09:09 AM
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Our electric is only about 11 cents a kWh. About $70 a month. This is a temporary solution until a meter is installed. I'm happy to pay in the interim given that I spearheaded purchasing the fountain without realizing we'd have such a power problem.
 
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Old 04-18-17, 08:39 AM
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Got two bids and the lower price was $2,300 to install rack, meter enclosure, conduit to transformer, 100 amp outdoor service panel, grounding, trenching 20amp 120v wire to new receptacle about 30 feet away near pond bank, plus the permits.

I still wonder if it might have been cheaper to go with a smaller 3/4hp 230v 4amp fountain and bury a new 10 gauge wire from the existing meter 700 feet away. Would have increased the price of the fountain by $500, plus the wire, plus all the trenching, plus boring under the road, plus the new outlet/breaker. Probably not.
 
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Old 04-25-17, 07:01 PM
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Here is the finished product....

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Old 04-25-17, 07:08 PM
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Looks very nice. Thanks for the follow-up .
 
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Old 04-26-17, 05:32 PM
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Very nice! I hope everybody likes it!
--------------------------
 
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Old 04-26-17, 07:42 PM
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I've gotten lots of compliments. It is a real show stopper. Now they want similar fountains in our other two ponds. We're going to have similar power problems but next time I'll consult an electrician to pick the best combination of fountain and wire run before I order. The 230v versions are so much more expensive that they aren't necessarily the way to go, but they might depending upon the cost of the cable run.
 
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Old 04-27-17, 12:09 PM
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Looks nice! Glad it turned out well. Don't worry about the other plan -- boring under the road alone could have soaked up your whole budget.
 
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Old 04-27-17, 05:29 PM
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Now look what you started!

The advantage about using higher voltage motors are they draw less current, so you can use smaller wire and have less voltage drop.
 
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