Power Lines

Sammynels · Jul 8, 2015

Was flying way too close to a service drop tonight and the interference made my UAV crazy and I lost connection. Next thing you know, my video feed comes back and I'm bouncing up and down off of a power line until I lost signal. I tried to CSC, nothing. Learn from my mistake. I lucked out and only need a new set of props and needed to reconnect my GPS ribbon cable. Ugh.

Sammynels · Jul 9, 2015

And battery popped out of course

Dome · Jul 9, 2015

Oh oh power line are enemy no.1 of p3, but RC in general ...stay at least 40mt away in every direction!!!

ianwood · Jul 9, 2015

This is odd. I've flown very close to high voltage power lines without any issues. It's when you hit them that they're a problem!

pstockton · Jul 9, 2015

Has anyone tried flying close enough to a large pylon to take inspection video?

Dome · Jul 9, 2015

Power middle or high tension line are really dangerous for RF appliance. The more current flows in there the more you risk an rf blackout. Why risk?

Dmacken1 · Jul 9, 2015

Wow this just made me realize something. My home is in a cal de sac. And my electrical panel for my home is not on the garage side of the house. This means my "Service Drop" runs through my front yard to my service panel on the other side of the house. And this front yard area may be where I have been taking off from and also calibrating my compass. I have never had a bad flight but this is certainly something to consider. Electrical lines underground and how they may effect my setup prior to flying.

F6Rider · Jul 9, 2015

I have a 10,000 volt line running along my back property line, was checking my solar panels for dirt (more fun than climbing on the roof) and flew within 20' of them without issue, may have to rethink that next time.

ianwood · Jul 9, 2015

Dmacken1 said:
Wow this just made me realize something. My home is in a cal de sac. And my electrical panel for my home is not on the garage side of the house. This means my "Service Drop" runs through my front yard to my service panel on the other side of the house. And this front yard area may be where I have been taking off from and also calibrating my compass. I have never had a bad flight but this is certainly something to consider. Electrical lines underground and how they may effect my setup prior to flying.

Good observation. Important to avoid for calibration and take off. Shouldn't be an issue when you're in flight though.

Buckaye · Jul 9, 2015

Sammynels said:
Was flying way too close to a service drop tonight and the interference made my UAV crazy and I lost connection. Next thing you know, my video feed comes back and I'm bouncing up and down off of a power line until I lost signal. I tried to CSC, nothing. Learn from my mistake. I lucked out and only need a new set of props and needed to reconnect my GPS ribbon cable. Ugh.

sounds like you got really lucky on the damage

that's good luck!

Sammynels · Jul 9, 2015

Yeah. I'll tell ya, I have been flying RC for years and I have flown my P3 with precision with no incidents until now. SOB! Lol! Every dog has his day fella's. Yesterday was my day!

shipdriver · Jul 9, 2015

I did a shoot at a state park where transmission lines essentially bisected the park at elevation. I ended up dividing the shoot into below the lines where I could set a max attitude underneath them (I made a 20m buffer) and then above the lines. Since I couldn't set a minimum altitude, I just kept well above them. The nature of the park terrain meant that everything was LOS. I did at one point, when I was above and beyond the lines, lose the connection for what seemed Iike about 20 sec, but it just hovered in place there until the signal came back. Planning the shots around the transmission lines was my primary concern that day. Here is the video from that morning:

eseckinger · Jul 9, 2015

Have high voltage lines behind my house and flew my p2 and p3 lots of times no issues. I go up 250 plus though.

Dome · Jul 9, 2015

Underground power lines are also a weird reason why you can't make a correct compass calibration sometime, specially in a city area.

walker16 · Jul 9, 2015

Dome said:
Power middle or high tension line are really dangerous for RF appliance. The more current flows in there the more you risk an rf blackout. Why risk?

Might be emf from the high voltage (14k and up)
The way ohms law works is that the higher the voltage the lower the current.

That's why people can be hit with a taser with 500,000 volts and live cause the amperage is very low but 120v with say 40 amps could kill you instantly.

Sorry I got off topic but I'm an electrician and just got my first phantom so that's about the most I can contribute to this forum right now!! [emoji106]

acherman · Jul 9, 2015

I flew down to these railroad tracks, with the power lines between me and the P3 (I was at the highway in the small clearing you can see on the left of the frame). No line of sight, probably a couple hundred meters away. The lines on the right aren't power, they are rock guards for the tracks/trains.

N017RW · Jul 9, 2015

walker16 said:
Might be emf from the high voltage (14k and up)
The way ohms law works is that the higher the voltage the lower the current.

That's why people can be hit with a taser with 500,000 volts and live cause the amperage is very low but 120v with say 40 amps could kill you instantly.

Sorry I got off topic but I'm an electrician and just got my first phantom so that's about the most I can contribute to this forum right now!! [emoji106]

Are you referring to say an AC motor that draws 10 amps at 120volts but 5 amps at 240volts?
This is because of the phase difference of the two 'hot' legs but the power consumed (watts) is the same.

Is this what you meant: that higher voltage requires less current for the same Power?

Now with regards to ohms law, an increase in voltage results in an increase in current.

Current (I) = volts (E) / resistance (R)... I=E/R
As Voltage increases Current MUST increase as well.

Chuck Young · Jul 9, 2015

walker16 said:
Might be emf from the high voltage (14k and up)
The way ohms law works is that the higher the voltage the lower the current.

That's why people can be hit with a taser with 500,000 volts and live cause the amperage is very low but 120v with say 40 amps could kill you instantly.

Sorry I got off topic but I'm an electrician and just got my first phantom so that's about the most I can contribute to this forum right now!! [emoji106]

So I do communications at a Hydroelectric power plant. Pretty sure 60 milliamps is enough to kill under the right circumstances.

Chuck Young · Jul 9, 2015

N017RW said:
Are you referring to say an AC motor that draws 10 amps at 120volts but 5 amps at 240volts?
This is because of the phase difference of the two 'hot' legs but the power consumed (watts) is the same.

Is this what you meant: that higher voltage requires less current for the same Power?

Now with regards to ohms law, an increase in voltage results in an increase in current.

Current (I) = volts (E) / resistance (R)... I=E/R
As Voltage increases Current MUST increase as well.

Here is what I am guessing

Right now we are generating electricity it is at 6,900 volts at 1,100 amps per phase and 3 phases. After we put it through the power transformer in our switch yard it goes down the high tension line at 69,000 volts and 110 amps per phase. The higher the voltage the lower the current can be for an equal amount of power. Probably what Walker16 was referring to if I had to guess.

N017RW · Jul 9, 2015

Chuck Young said:
Here is what I am guessing

Right now we are generating electricity it is at 6,900 volts at 1,100 amps per phase and 3 phases. After we put it through the power transformer in our switch yard it goes down the high tension line at 69,000 volts and 110 amps per phase. The higher the voltage the lower the current can be for an equal amount of power. Probably what Walker16 was referring to if I had to guess.

That's what I asked him but I agree that must be his intent within the context of distribution.