EC5 desoldering negative lead

[atomiccomp]

My compass 7HV has twice now during flight de-soldered the negative lead from the EC5!

On both occasions after autoing down the leads were only mildly warm and the batteries and ESC were barely warm to the touch.

Maybe it's a coincidence but this has only started since I installed a HW phase sensor and switched from the internal gov to the vortex gov so I could use the auto bail out.

ESC is a YEP 180 HV with a 800MX motor running 1950 and 2050 headspeed. using 2 Opti 5000 6s 30c's in series and have two connectors on the ESC lead.


They were correctly soldered on and have worked perfectly during the last year or so. The EC5's look in good shape with no pitting or corrosion. This has happened with two different battery packs.

Has anyone else encountered this sort of problem with EC5's?

[kenny d]

Twice with badly soldered joints on second hand heli's both on ec5's , I've never had a problem with the ones I've done myself

[torque to twist]

Take a look at the ramp up in the vortex it can be very aggressive on start up it. You may be using huge current on wind up.
If you are using longer blades this will impact start up.
With a180 it exceed the rating of the EC5 without breaking a sweat!

[philipjdall]

I had the same problem. I now don't use ec5's.

Apparently I'm a terrible solderer too...

Save your heli, switch to something better.

[Pj1969]

I had a problem on a heli I bought 2nd hand and the wires looked mint, but on maiden the positive de soldered and it went in. Looking at the joint it seemed to be sh*t solder and only just about pushed in the connector. The solder these days is pants and it pays to shop around and get some decent stuff, I even go to old school garages with old fellas working in them asking if they have any solder laying around as it's normally pure lead lol. Flux paste also helps, not saying that you can't solder, but going on my experiences.

[Mike Sanders]

switch to something better.

What?

[Granpappy]

Sounds like your new Governor set up has increased current draw on the packs. I use supra X connectors on my 7HV. If you change connectors I would also reduce the flight time on the first flight just to check the pack state after say 4 minutes. Don't want to puff the batteries. I don't know what voltage your receiver supply is but HW phase sensor is 6 volts max apparently.

[atomiccomp]

Thanks for the responses guys, I have to say that the soldering on the connectors is bang on. I use a large iron and 60/40 lead solder and have never in 4 years of flying 12s setups encountered anything like this!
I even got another experienced solderer to re-solder the joint and it still failed. he thought it was a fluke however I've seen this behaviour before years ago on a 500esp with 3mm bullets on the motor which did the same thing. It de-soldered
everytime it was flown. Switching to 4mm bullets cured the issue.
The strange thing is it took 3 flights to fail again and it was only doing 1950 head speed, whereas initially it was at the higher head speed the first time it failed.
I'm wondering if the gov gain is too high. Other than that I'm stumped!
I really don't fancy changing all my connectors to a different type, as I use the batteries on other 700's.

I might try the old gov setup and see if the issue goes away. I'm sure I can live without auto bailout..maybe.

I have to say this 7HV has been no end of trouble (It's probably not the models fault), ranging from failing to pull out of a dive-which I never got to the bottom off, s-bus connector leads failing and now this! Each time it's been an expensive do, requiring new blades, shafts and so on.

[waveydavey]

When we're talking about desoldering we're talking 180 degrees C, the plastic surround would be in bits if that were the case and more than likely anything else it was in contact with. So I know theres a number of EC5 failures but not sure it's down to heat alone

[atomiccomp]

When we're talking about desoldering we're talking 180 degrees C, the plastic surround would be in bits if that were the case and more than likely anything else it was in contact with. So I know theres a number of EC5 failures but not sure it's down to heat alone

I agree Dave, however I can't see how else it could go? The connectors were only slightly warm to the touch after I retrieved the model. From experience he plugs take ages to cool down when I solder them at 450 degrees c.
I did notice last week before all this that the ESC leads were quite hot when I disconnected them after a flight.

[hanson]

Thanks for the responses guys, I have to say that the soldering on the connectors is bang on. I use a large iron and 60/40 lead solder and have never in 4 years of flying 12s setups encountered anything like this!
I even got another experienced solderer to re-solder the joint and it still failed. he thought it was a fluke however I've seen this behaviour before years ago on a 500esp with 3mm bullets on the motor which did the same thing. It de-soldered
everytime it was flown. Switching to 4mm bullets cured the issue.
The strange thing is it took 3 flights to fail again and it was only doing 1950 head speed, whereas initially it was at the higher head speed the first time it failed.
I'm wondering if the gov gain is too high. Other than that I'm stumped!
I really don't fancy changing all my connectors to a different type, as I use the batteries on other 700's.

I might try the old gov setup and see if the issue goes away. I'm sure I can live without auto bailout..maybe.

I have to say this 7HV has been no end of trouble (It's probably not the models fault), ranging from failing to pull out of a dive-which I never got to the bottom off, s-bus connector leads failing and now this! Each time it's been an expensive do, requiring new blades, shafts and so on.

Have you changed the connectors on the end that didn't desolder? The esc side?

[atomiccomp]

Have you changed the connectors on the end that didn't desolder? The esc side?

It was the ESC side that de-soldered. I haven't changed them yet. This happened at a show at the weekend so I was low on spares.

[_tj_]

I've just brought a load of XT 150 connectors to change to.
I've been using XT90 on my 550x and although they seem good and reliable for that.

I don't want this to happen on the 12s 700 setup.

Hopefully they will take away any doubts I have with the XT90 on the 700.

[waveydavey]

If I get time tonight I'll try to get enough transfer heat on a connector and see if I can pull the core out, 60/40 solder and a 150W iron.

[Mike Sanders]

I have soldered up dozens of EC 5 connectors and I have only ever had one fail. That too was the negative to the ESC. I still don't know why it failed and I have put it down to a lack of attention while wielding the soldering iron. I now check the connector every week, just by giving it a pull and it seems OK. Keeping my fingers crossed.

I don't profess to be an expert at soldering, although I have been doing it for 50 years so I think I know something about it. The best advice I can give anyone is, avoid lead free solder like the plague.