Limitless Any Benefit to having separate Battery for Cooling FAn?

[ArrmaFreek2022]

Arrma-Freaks, question. Does anyone know if there is truly any benefit to having my fans connected to a separate batter source over having them connected directly to the receiver on Speed Runs?

I wondering if its worth the extra weight and whether there is any battery drain from the Fans during the actual fun (voltage, amps etc)

 

[SrC]

Depends on the Fan(s) you are using. Large 12 volt fans requiring a dedicated 3s pack are heavy as well, not just the additional dedicated "Fan pack". With speed running , I don't think weight is much of an issue to some extent. Some would argue that they want the Rx and ST Servo to get exclusive use of the BEC circuit. A failsafe of sorts. Adding fans to that circuit can be a liabiity. Simply depends on the size/power requirments of the fans you choose..
And with Hardcore speed passes,, it is rare you keep running that mains lipos for some time, like you do with bashing. You make several passes and that's it. Replace or charge those packs again for continued passes. A temp gun will determine if you even need a fan(s). A good ESC/ Motor combo setup usually doesn't need fans for basic speed passes. Cooldowns between each pass is always par for the course. Temp gun in hand.

 

[DLK83]

I'm not a speed runner, but my short answer would be no- and yes.. the weight from a small 2/3 cell is negligible, so I wouldn't worry about that part of it... if you talk to Promodeler, they highly encourage a separate battery for the steering servo to keep "clean" power going to it, and avoid potential "brownouts"... that being said, I've been running one of his big servos in an Xmaxx for awhile now, powered from the bec in the esc, exactly what he says not to do, and it's been fine, knock on wood... I like the separate battery for fans because if you're running big fans(that pull an amp or more ea), that can pull down your main batteries if you're running long enough... again, most of this isn't applicable to speed running, more for bashing, but nonetheless

 

[rotauq]

Speedrunning you don't necessairy cool during the run, but in between runs. And you don't want that idle time flooding your logs.
Depending on the car i either have a fan on it and plug in the battery during the cool down, or i use a complete seperate fan unit which isn't in the car at all.

I do run lights for long distance visibility. When you run with 2 batteries, i'd advise not to pull power from a single battery.(from the balance lead for example)
Best add a vrm at your main leads to convert it to 5v or 12v, so any drain is equal amoungst the batteries.

 

[SrC]

+1
Don't just tap off one pack's bal. lead to power the Fan(s). Not fundamentally correct to do.
This keeps both packs from staying matched, while in series under load. With tandem lipo packs..

 

[Donutjohn]

Arrma-Freaks, question. Does anyone know if there is truly any benefit to having my fans connected to a separate batter source over having them connected directly to the receiver on Speed Runs?

I wondering if its worth the extra weight and whether there is any battery drain from the Fans during the actual fun (voltage, amps etc)

in my mega 4x4 i use a power hobby fan from a scx24 7.4v battery then the esc fan runs off 3rd channel.

It takes a good 5mins of bashing to need either fan.

Id say for speed runs get 0 fans and also the smallest mah to get down the track.
With 1/1 speed passes sometimes they could only make it 1/4mile.
F1 cars are desined to last 1 f1 race.
Lemans cars are designed tolast 24 hours.

If i was you id have mine set to last 5 mins.

Im really just looking to post. Hope this helps