700L ESC and RX placement

[rhodesengr]

I am starting a 700L build. I see most guys are mounting the ESC on the side in the front rather than either of the two positions suggested in the manual: position 1 next to the motor or position 2 behind the main shaft. Curious why more people or not using Position 2. Seems like the ESC would get better cooling in the back.

For RX placement, it seems the Align sort of assumes you are just going to use Sats. I plan on using a BD3SX with a full RX (AR8000). They don't really give you a good location for a full RX near the FBL mounting stage. My RX battery will take up all of that mounting area. Just looking for ideas.

[dchekas]

I've run the 160HV with the Align 850MX 490kV all summer without any overheating issues, and my ESC is mounted inside the front receiver tray. The ESC comes down warm, but not burning hot.

I mount my receiver on the opposite side of the front receiver tray. There's several holes allowing you to run wires back towards the motor, and then up to the FBL unit.

[rhodesengr]

OK. Thanks. I've seen some RX mounted that way. The 3SX comes with a pretty short cable loom so I'll have to see if it is long enough. They sell longer ones but a) I have to order it and b) they are like $25. I have various ideas but just thought I'd ask and see what other have done. I just did a 700N DFC gas conversion and had to mount everything on the back due to heat issues with the gas engine. I am trying to stay closer to stock intentions this time.

[magbarn]

I've found a more than 10 degree F difference between mounting the 120hv underneath the canopy vs behind the main shaft where it gets plenty of ventilation. I'm assuming the dominators 160HV is much more robust than the 120HV and should be ok under the canopy. Then again, heavy collective use and ambient temps would make a big difference too.

[Trexwilly]

The L comes with a Edge 120HV not a 160HV the Top comes with a 160 out of the box...

I put the Heli jive in the front like dchekas

But I am no stick banger so I think how you fly is an important consideration?

[xokia]

My ESC is the 160 which is mounted on the back never comes down hot. bd3sx mounted up front. I just run sats. There is plenty of room upfront though to run a full RX.

[el guapo]

mounting on the back (position 2) is no fun. it means you have to connect the lipos to the ESC at the back. which makes loading lipos inconvenient.

[rhodesengr]

Until I I try to work out the wiring myself its hard picture which way is easier. But, it occurred to me that if I mount the ESC in the back, I can use position 1 for the AR8000. The 3SX wire harness will easily reach in that case.

I do want to say that so far I am impressed with the kit and build. It is going together very smoothly.

[Trexwilly]

About a dozen flights on mine so far, having the ESC up front, and a couple of trays, makes this the easiest heli evar to insert the pack, and go fly!

[el guapo]

Originally Posted by Trexwilly

About a dozen flights on mine so far, having the ESC up front, and a couple of trays, makes this the easiest heli evar to insert the pack, and go fly!

+1
I had the ESC on the back of my V1. it was so annoying shoving the lipos in lead first. the balance leads always got snagged and damaged.

[Pitch-Itch]

Originally Posted by Trexwilly

The L comes with a Edge 120HV not a 160HV the Top comes with a 160 out of the box...

I put the Heli jive in the front like dchekas

But I am no stick banger so I think how you fly is an important consideration?

You're kind of a stick banger bro. You fly hard to me!


How are you liking the 700L? I'm trying to decide between one of these and a G570.

I should note, I absolutely love my 450L so that's why I'm very intrigued by the 700L. I also want a big heli, not sure the 570 would be a big enough step up from my Cell 500 (which is true 500 size) to satiate my big heli thirst.

[rhodesengr]

does anyone have a photo with the batteries in the tray and ESC mounted? Just looking to see how people route the wires.

[Trexwilly]

Davis I am loving the 700L

This dude is a Bad azz and the kit is very slick, servos are increadable, the CNC work is first rate... I am very pleased I chose this 700, so many to choose from...

Battery pic...

[xokia]

Originally Posted by el guapo

+1
I had the ESC on the back of my V1. it was so annoying shoving the lipos in lead first. the balance leads always got snagged and damaged.

If you heat shrink both packs together its not that bad at all. Admittedly if you just slam then in their you can snag a wire. But if you take 10 seconds its a fairly low maintenance task.

Originally Posted by rhodesengr

does anyone have a photo with the batteries in the tray and ESC mounted? Just looking to see how people route the wires.

I'll try and remember to snap a photo later.

[rhodesengr]

Originally Posted by xokia

I'll try and remember to snap a photo later.

hey that would be great. I've been going back and forth about front vs back. Back seems better for cooling but front seems easier to rout the wire and less chance for interference with the main shaft. I may try front mount first and see what sort of temps I get in the log and then if it is getting too hot, I guess its not too big a deal to change it. Since I am not planning on running high headspeed, it sounded like heating is more of a problem.

[Superholgi]

Hi there, I finished my 700L build some two weeks ago and since I put extra (waddayacallit...) fabric hose (?) around the servo wires, it would have been close to impossible to mount the ESC in position 2 (back plane)... the motor wires simply would not fit any more, and I did not want to run them outside the frame. So I, too, went for the side mount position in the nose.
Temperatures were somewhat around 80-84 degrees Celsius at 1900 rpm. It was a little better at 2000. What I did, I added a cheap 40x40 mm fan (2.60 $) and just zip-tied it onto the ESC. Now I can see my temperature curve levels out at around 70 Celsius and it stays there. It's OK like that.
I'd like to run headspeeds less that 1900 but have been warned not to trickle too much out of the Edge 120HV. Not decided what I'll do yet; I'm still getting used to the bird as my second largest is a 600 ESP which is way lighter and flies way more elegant - guess I still have to get used to the 12S power, and rely on it.

Now, someone asked for the battery wiring... I use daisy-chained 6S batteries and apart from a lot of cabling in the nose (which is big enough, luckily) I am happy with the front mounted ESC.

Want pics?

[xokia]

Motor wires are routed down the inside of the frame underneath the main gear above the battery. Some people like to slide them in there next to the main shaft around those servos. I didn't like the clearance on that. Extended the motor wires six inches and kept everything inside the frame.

[el guapo]

Originally Posted by xokia

If you heat shrink both packs together its not that bad at all. Admittedly if you just slam then in their you can snag a wire. But if you take 10 seconds its a fairly low maintenance task.
.

its not bad, I did it for years. its just sooo much better doing it the other way.

[davehour]

I really don't know why many say the 120HV runs hot at 1800. I do practice slow flights at all orientations running 1800, and sometimes stop to hover, and the temp rises to 170F (about 77C). The flight duration when running at 1800 doing the practice is 9 minutes, and the batteries still end with good voltages.

I live in a tropical climate where the ambient temp is 93-98F (about 34-37C) most of the time at the flying field.

[rhodesengr]

Look like I will maiden tomorrow morning (Saturday). I went with the front ESC mount at least for now.

So with all this talk about ESC temperature, what should I be look for? What is considered an OK temp and what is too hot?