pros and cons between JST and XT60 plugs

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PiperCPO

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Hi all,
About to buy some batteries for my DD setup and was looking for some pros and or cons between the JST and XT60 connectors since 2C lipos come with either. My main question is there a "locking" feature on either. Last thing I want is for a "G force gremlin" getting in and disconnecting one or both my batteries from my Quantums. I am still working on designing my AV bay layout and am going to try and horizontally mount the connectors to keep the Gremlins at bay, but I have this sneaky little Irishman named Murphy lurking around myself lately. I have not had any experience with either connector. I am more use to multipin rack mounts and cannon plug setups in the avionics I have experience with.

Thoughts appreciated.
 

jd2cylman

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I'm just starting with the LiPo's myself, but the JST seems to be a pretty good connection. Not sure how tight it will be after hundreds of cycles of connecting and disconnecting though. One way to find out! :wink:
 

Incongruent

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Have you considered mounting the battery instead of the connector? If you make some slots on the sled, you can zip tie the battery directly to the sled instead of relying on the connector to maintain continuity.
 

ttabbal

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The XT60 are a tight friction fit. I prefer them over JST, at least the ones we get cheap from hobbyking.com and friends. Real JST are supposed to be better. For what we do, XT60 are overkill. XT30 are a smaller version that should be fine.

Servo type connectors are available with locking tabs or add on clips. They don't have as much current capacity, but they are probably enough for what we do. Just a few thoughts.
 

rharshberger

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I use JST connectors in all my Av-Bays for the battery to altimeter connection, usually I leave enough distance between the batteries hold down zip ties that the connect JST's can be cinched between the zip ties at which point its extremely difficult to disconnect without removing the zip ties.


L3Build140.jpg L3Build117.jpg
 

OverTheTop

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I usually use JST, as the XT is just big and bulky overkill for the currents I normally run. My Vertical Trajectory System does run an XT connector just because of the draw from the servos.

I have not had a JST come undone during flight. I normally glue (Loctite 401) one side of the connector to the sled, with the separation axis being horizontal. For high-G flights a little dab of hot-melt glue pins the movable connector to the sled for extra security.
 

jd2cylman

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Have you considered mounting the battery instead of the connector? If you make some slots on the sled, you can zip tie the battery directly to the sled instead of relying on the connector to maintain continuity.
The batteries are always mounted securely. You don't want one of those swinging around in the AV bay beating the snot out of your flight computers... I think that would be bad and you will not go towards space today... :wink:
 

OverTheTop

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Have you considered mounting the battery instead of the connector? If you make some slots on the sled, you can zip tie the battery directly to the sled instead of relying on the connector to maintain continuity.
I use cable ties to hold the batteries to the sled, but I have Velcro between the batteries to take the shear force. The cable ties just need to hold the battery down to prevent the Velcro peeling. That way you don't have to use excessive force on the cable ties, which is probably not good for the LiPo batteries.

This particular one has been launched at 62G successfully:
Sled1resize.JPG
 

Incongruent

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The batteries are always mounted securely. You don't want one of those swinging around in the AV bay beating the snot out of your flight computers... I think that would be bad and you will not go towards space today... :wink:
Thabks for the clarification. I was wondering if the batteries were getting mounted by the connectors since it didn't seem plausible at the time that the inertia of the wires and connectors could separate the connection.
Though thinking about it, if the wires were pulling and the connector was loose, it could happen.
 

Bkdoubleu

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Have you considered mounting the battery instead of the connector? If you make some slots on the sled, you can zip tie the battery directly to the sled instead of relying on the connector to maintain continuity.
Good advice
 

PiperCPO

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I am playing with several configurations, batteries horizontal or vertical, and yes they would be secured Incongruent. My concern was the slack in the wiring and the movement of the wiring at the time of high "G" load. I have a "hardwired" respect and dislike, for a certain "wee Irishman" by the name of Murphy. My inquiry was regarding the physical characteristics of the JST and XT60 connectors and if there was a locking mechanism or sufficient friction that with minimum wiring movement, the connectors would not separate.

Thanks for the ideas Over. I just got through looking at some specs on the XT60s and concur that the currents involved would not warrant the XT60s. I will have to see if I can pick up some JST leads from my local hobby shop they cater more to the RC car and small helo crowd. I will go ahead and order some LiPo's with the JST connectors.
 

OverTheTop

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Whenever you have a part that weighs "x" amount that you are trying to mount, multiply "x" by the maximum accel of the rocket (in G's). It can give you a bit of an estimate of how much you need to resist with your mounting. Scary numbers sometimes :eek:
 

Wayco

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I use JST connectors for all my LiPo's, just tape them down with packing tape. Usually, they are secured horizontally, but some configurations require otherwise. Never a problem with them becoming disconnected.
You can get packs of 10 (male, female or both) from Hobby King, but look for the US warehouse or you might be waiting for quite a while for the boat from China.
 

NateLowrie

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If your worried about the JST plugs coming undone, just put a dab of hot glue at the connection point. It will increase the force required for pullout and will peel off easily. That said, I have never had a problem with JST just friction fit in. Still, for total risk mitigation I would put a locking connector on like molex minifit jr.
 

OverTheTop

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If your worried about the JST plugs coming undone, just put a dab of hot glue at the connection point.
I use a similar method, but the hotmelt just goes onto the wires as they exit the moveable plug, pining them to the sled. Very easy to remove and does not foul the connectors.

Either method (or others) will work.
 

PiperCPO

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Thanks for the suggestions. I tend to over think the situation and forget the simple solutions.
 

T-Rex

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My electronics are set up with JST connectors. My big problem seems to be finding batteries with the same connector. I recently bought 4 new batteries with a different connector so I will have to go back and retrofit my electronics.
 

OverTheTop

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My electronics are set up with JST connectors. My big problem seems to be finding batteries with the same connector.
There are so many different batteries with different connectors out there. I just crimp on whatever I need, as I am lucky enough to have access to JST crimpers.

I have actually started using the balance connectors rather than the red JST. Extra pins can give a bit better retention force. Not much difference either way though.
 

T-Rex

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There are so many different batteries with different connectors out there. I just crimp on whatever I need, as I am lucky enough to have access to JST crimpers.

I have actually started using the balance connectors rather than the red JST. Extra pins can give a bit better retention force. Not much difference either way though.
The difficulty with connectors is my own doing. I decided that I wanted to use matching 1s batteries for everything and looked for the smallest I could find. I just bought 4 200mah blade type batteries to power my EggTimers. The smallest I could find with the red connector is 600mah and I don't need that much power. As soon as I locate my solder again, I'll swap out the power connector to match the 1.25mm connector on the new batteries. I have 2 600mah cells which I will continue use to power the pyro channels.

I will also have to fashion converter cables for my charger since my charger is set up for the red connectors. In reality, just a minor inconvenience.
 
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