Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[bj]

No really sure where to post this so redirect if necessary....

Does anyone know the rating of 4mm gold plated bullet connectors or where to find the necessary information?

Thanks

... having written the above I did find https://sites.google.com/site/tjinguytech/reviews/rc-connectors but comments, please.

[derekwarner]

bj........Courtesy of Google...........Derek
4mm Gold Plated Bullet Connectors with Heat Shrink for attaching your Motor to your ESC and other electrical connections
These standard 4mm bullets are rated for up to 70A to 80A of current.

[ukmike]

That must be Chinese amps, certainly not European amps.

Good quality 4mm connectors good for about 30amps for several mins.

The 70-80 amp figure is for seconds only, then they could melt.

[derekwarner]

  ...certainly not disputing your comment Mike......my posting was copied straight from Google.......Derek 

[spearfish99]

Graupner used to sell some rated at 80 amps.

Some people, however, worry about the amps the plugs will take while using wire that will no way handle high currents. It is important to match wire size to connectors to avoid shorts, fires , etc

[bj]

... having written the above I did find https://sites.google.com/site/tjinguytech/reviews/rc-connectors but comments, please.

I copied and pasted the above link but it does not seem to work. Hopefully, if you go on to https://sites.google.com/site/tjinguytech/reviews and then select "Choosing an RC Connector" under "Solutions" that seems to bring up the page. Maybe it is related to the "s" in prefix of https......... The text is worth the read

[inertia]

As you say, it's the 's' in https that's the problem. I read the article with much interest and then I found the bit which made me whoop and throw my hat in the air ;

 First up is the wire size on the esc input. The esc makers know what their esc can handle and so they will use the appropriate wire size for the esc. Say a common 450 sized esc has a wire size of 16awg. A quick online search for "16awg amperage" will tell you that the wire is rated for a maximum average amp draw of 15-22A. So it would be safe to assume that your esc is designed to handle no more than 15-22A average amp draw no matter what the esc has written on the side.  (My highlight)

That makes at least two of us who are highly suspicious of very high-power ratings in ESCs with 'normal' thickness cable fitted. One of my customers put it very succinctly - "That's why fire engines don't use garden hoses". Worth thinking about, is that.
DM

[malcolmfrary]

3 hats in the air, Dave.  I also liked the preceding paragraph in the link regarding calculating current draw - 


As it turns out none of the above numbers mean squat when trying to figure the average amp draw. They can tell you the maximum potentials and limits but that does nothing for you, as you actually decide the amps draw by how you setup and fly the heli. There are basically 2 approaches to finding the average amp draw, one is to actually measure it and the other is to make an educated guess.


So much for the flyboys who claim that "there are tables of figures for flyers, why not for boaters?".  Turns out that there is just as much "poke and hope" for them.  Just change the words at the end of the second sentence so that they relate to boats.

[thething84]

so what do most people use as connectors on here. I know tamiya connecters are not great and have a habit of melting. I am currently looking at deans connectors.

[spearfish99]

Hi All

  Deans connectors are reasonable for relatively tame motor setups. They are probably fine for setups that run at 20amps or less, over that and they can start to get a bit warm.  They can be quite awkward to solder until you are used to them, but do have the advantage of polarising the connection automatically, i.e., it is difficult to connect the wires incorrectly.

 Personally , I prefer bullet connectors on my boats, most of which are offshore racer style boats of about 36" long and powered by 700BB motors. These are run on 2x7.2v nimh in series to give 14.4v and are fitted with 4mm gold bullets.

 Recently I have built a 40" Cigarette with a Turnigy T600 1400KV outrunner brushless motor designed to run on 6S (i.e. 22.2v) LIPO cells. On this set up, I have gone up in size to 6mm connectors due to the potential current this set up may pull. I have also used heavier gauge (good quality) silicon wire than on the brushed boats.

 I must admit that I have to watch for polarity issues when connecting up the boats as some time ago I chose to go a slightly different route to what is considered normal.  When I replace the Tamiya or Deans plugs on my batteries, I install two female connectors on the battery, fully sheathed in heat shrink tubing. All my motors and ESC's that plug into them have the male  connectors. Power OUT from the ESC is again female connectors.

The norm is one male and one female connector on each battery but the male connector unless kept insulated , to me at least, has always seemed to have the potential (no pun intended) to short out. Everything is colour coded, so with a little care this system works for me, others may not agree. I just prefer anything on the output side of the power system to have female connectors

[Steve J]

Deans connectors are reasonable for relatively tame motor setups. They are probably fine for setups that run at 20amps or less

I beg to differ, IMHO genuine Deans Ultras are good to at least 50 amps.

Most of my LiPo's above 1000mAh have Deans Ultra connectors. The exceptions are ones used in a catamaran where I have two packs in series and use 5.5mm bullets.

Steve

[emlra]

Hi All

 

 Personally , I prefer bullet connectors on my boats,
 

 Recently I have built a 40" Cigarette with a Turnigy T600 1400KV outrunner brushless motor designed to run on 6S (i.e. 22.2v) LIPO cells. On this set up, I have gone up in size to 6mm connectors due to the potential current this set up may pull. I have also used heavier gauge (good quality) silicon wire than on the brushed boats.

 I must admit that I have to watch for polarity issues when connecting up the boats as some time ago I chose to go a slightly different route to what is considered normal.  When I replace the Tamiya or Deans plugs on my batteries, I install two female connectors on the battery, fully sheathed in heat shrink tubing. All my motors and ESC's that plug into them have the male  connectors. Power OUT from the ESC is again female connectors.

The norm is one male and one female connector on each battery but the male connector unless kept insulated , to me at least, has always seemed to have the potential (no pun intended) to short out. Everything is colour coded, so with a little care this system works for me, others may not agree. I just prefer anything on the output side of the power system to have female connectors

That is exactly how I blew 3 regulator chips on my Hermes last year!
I now fit a Female socket to the battery side of the +ve feed and a male on the -ve side.
-ve is is normally used as the common return on most circuits so little chance of cross polarising now!
 
Rex

[spearfish99]

I beg to differ, IMHO genuine Deans Ultras are good to at least 50 amps.

 Steve,

  Would probably agree with you on genuine Deans Ultras.  Most of those around, however, tend to be Chinese lookalikes which are not as good.  As I mentioned before, I think that the quality of the wire being used with them and the soldering used to attach them is as important as the connector itself

[Steve J]

Most of those around, however, tend to be Chinese lookalikes which are not as good.

That is true of all connectors, not just Deans. Cheap components are often a false economy.

I think that the quality of the wire being used with them and the soldering used to attach them is as important as the connector itself

Very true.

Steve

[Steve J]

I now fit a Female socket to the battery side of the +ve feed and a male on the -ve side.

I have a clubmate who does this. On at least one occasion he has connected a battery to itself.....

I do it myself for the batteries in my catamaran, but I much prefer keyed connectors for general use.

Steve