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BANTERMAN894

Can i use 16 awg wire for this lipo?

I would really like to know if 16 awg wire can support this lipo?
Franksie

I see no reason why not
BANTERMAN894

I was just wondering as on a chart it said only 50 amps could be used but this lipo is 65 but ill try!
Franksie

I use 16AWG with my 65-135c 500mah 3S LiPo.
Boff

A Nerf blaster will only draw what it needs at the business end. That wired is rated to 50A continuous discharge and your LiPo will can output a maximum of 65A (burst or continuous, it doesn't matter). Only with Hellcats and a Honey Badger pusher do you push over 70A burst current, other systems (from memory) need much lower currents. A triple Rhino build, for example will draw 24A at stall based on 8A per motor.
OldNoob

As above.

You need to start with a logical process for component selection instead of randomly throwing stuff together.

1: Decide on motors based on how hard you want to shoot (fps) and how fast (ROF) this will set the next two stages.

2: Use the motor data sheet in The Vault to see your motor voltage- match it to a pack rating, ensure your pusher motor will work with chosen flywheel motors or use 3 the same.

3: Calculate the burst current load- Look at the STALL figure, multiply by the number of FLYWHEEL motors. Typically two. Then take the stall current of your pusher and HALVE it, as pushers gave gearing to lower stall and pull less. This is your BURST CURRENT. That is the ABSOLUTE MAX that the system will draw. Add a minimum of 10% safety margin, 20 is better. That is the burst rating you need for your PACK  and wire.

4. Choose biggest capacity pack that will fit the available tray space and has the burst rating you require. Remember discharge is related to capacity so more is more.

5: Choose circuit wire- It should meet your burst plus 10%. Remember the rating is max continuous current for ONE LENGTH of wire, so you have a bit of slack. More is always more. You don't need huge wires for pushers.

6: Check ancillary components e.g. Mosfets can meet burst current and consider overload protection e.g. fuses if you are going all out or building a large, complex loom.

7: Don't forget parts like heatshrink and connectors in your build cost. Kits can save you money here.

Build mod, enjoy safe blaster.
Boff

In addition to above, the continuous ratings for various plugs off the top of my head are as follows:

JST: 3A
XT30: 30A (duh)
Deans, XT60, Traxxas Black: 60A
XT90: 90A (also duh).

The above can handle higher loads for burst periods but it's not recommended to do so.
SSGT

Echoing all of the above (especially 16AWG 22A rating being continuous not burst - it can handle many times that for a short period - and motors drawing current rather than packs pushing current) although...

OldNoob wrote:
3: Calculate the burst current load- Look at the STALL figure, multiply by the number of FLYWHEEL motors. Typically two. Then take the stall current of your pusher and HALVE it, as pushers gave gearing to lower stall and pull less. This is your BURST CURRENT. That is the ABSOLUTE MAX that the system will draw.


...I'd still suggest using the full stall current of the pusher motor when calculating max current draw for pack burst rating selection. The gearbox simply trades speed for torque (or vice-versa depending on how it's geared) so the mechanical power at the output shaft of the gearbox is always the same (minus losses) as the mechanical power at the motor shaft.

Granted, in normal operation with a fixed external load, the load at the motor shaft will be less than it would if you had a direct drive from the motor (due to the gearing the motor effectively "sees" a smaller load than that is actually there), meaning the motor will draw less current driving that external load through a gearbox than it would if it were driving the load directly without the gearbox (you could, for instance, get away with a lower continuous current rating).

At stall, however, the external load exceeds the torque the motor can produce (with or without gearbox) so the current demand will be the same as if there wasn't a gearbox - the torque generated at the motor shaft will be the same as if there wasn't a gearbox but the torque at the gearbox output will be multiplied by the gearing. That means that at startup, or during a nasty stoppage that physically prevents the motors from spinning, the motors will still demand the full stall current for a short period of time (in the event of a "hard" stoppage that might be for anything up to a few seconds).

EDIT

Moved to Q&A and New members as it is a question.

Also, link fixed.

SSGT

BANTERMAN894

BTW Sorry might not have said that it's going in a stryfe!
OldNoob

Same process applies. Just ignore the bit about pushers.
SSGT- My pusher circuit has a PTC to protect it from stall, I forget other people don't do that.

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