Esc ??

[Walmsley2012]

Hi people, sorry to keep clogging up the forum with silly little questions but learning more and more each day. I have seen so many topics on esc and still this is still an area i cannot get my head around.

Im running 2no 7.2v 3300mah batterys in my ram bot, these in turn running my lovely 12v argos motors

I am now looking to get a pair on esc but this whole area in a blur to me.

Any recommendations on some cheap and cheerfuls??
Also any information on esc's is greatly welcome.

Thanks everyone

[maddox10]

Re: Esc ??

ESC's for feathers. Personal opinion/experience.
Electronise. Cost , ok. Bang for the buck, ok. Reliability, needs some work. Size, annoying. Control mediocre.
IBC. Cost, painfull. Bang fot the Buck good. Reliability high. Size problematic. Control fine.
Robot Power XXL. Cost, painfull. Bang for the buck, reasonable. Reliability high. Controle Fine
Robot Power Sidewinder. Cost, horrible. Bang for the buck, painfull. Reliability high. Control fine.

Random el cheapo RC model ESC's, waste of money. Smoke generators.

But. Botbitz, 2 Aussie roboteers are reprogramming and adapting brushless speedo's to be used for brushed motors. They get good marks for dependability, speed of service and bang for the Buck
Cheaperthan thisyou won't find atm.
But let me tell now, It's a 1 to 2 chance you'll blow these in any situation close to a real fight.
The 25A version should hold a tad better, but the quality from the supplier was dropping, so they don't have one in this range atm.

The TZ85
got good marks on bang for the buck, reliability and size. Cost is painfull. Same range as the Scorpion XXL. Control. No personal experience, but the drive of Tormenta 2 was good enough to win.

[Walmsley2012]

Re: Esc ??

Many thanks for your reply.You clearly have used a fair few esc's.

my original message wasn't hugely clear but im finding more trouble understanding what Amp Esc i should be looking at. 25a? etc. Or more so how the devil you work this out?

[maddox10]

Re: Esc ??

The amount of amps are depending on a lot of factors.

2 or 4 wheel drive. 4 Wheel drive needs a lot more amps.

High top speeds need more amps.

Very grippy wheels. More amps.

Team RCC's current Featherweights.
Hannibalito 3. Speed 900/MSR 12-54 Drive.130mm wheels. 4S A123 (13.2V) with Scorpion XXL. Bloody fast, extremely agile, but lacks pushing power due bad geometrics.

Hannibalito 4. 2wheel drive, Gimson 9.6V GR01's, 170mm wheels. 3S (11.1V)LiPo pack and Scorpion XL speedo (25A limited). Drives very controlable, but lacks pushing power.

Kashei. 2wheel Speed 900/MSR 12-72 drive. 100 mm wheels. 6S LiPo (22.2V) with Sidewinder. Ludicrous speed. Extremely nervous control due center of gravity positioning of the wheels.

[Ellis]

Re: Esc ??

For drills, assuming 1 per speedo, you're looking at about a worst-case scenario of 15a draw when stalled (changes a little depending on voltage but you're safe reckoning about 15a). Using that as a rule of thumb, a single speed controller of 15a continuous+ should run a single drill-scale motor safely, in most robot situations. So with that in mind, a 15a Electronize speed controller would control it happily, but the drive precision and bad customer service by Electronize doesn't help their case. That said, we have found the 30a models (more pricey, but still cheap as ESCs go) to be very reliable. They'd hard speedos to break as speedos go. They just result in clunky drive; they have a delay between fwd/rev as they're relay-based.

The Botbitz 25a models should run a single drill each comfortably. But as mentioned their quality is questionable. We haven't had experience with the 25a model, but we are currently running the 85a model (could take 3 drills or something stupid happily!) and we are very impressed for the price. Great customer service too.

Links: www.electronize.co.uk and www.botbitz.com

Also don't worry about asking too many questions, as long as you're not asking which direction it is to tighten a screw we're happy to help.

[RogueTwoRobots]

Re: Esc ??

as long as you're not asking which direction it is to tighten a screw we're happy to help.

That rules out being allowed to ask which direction it is to tighten a screw in a drill chuck then :wink:

[Ellis]

Re: Esc ??

as long as you're not asking which direction it is to tighten a screw we're happy to help.

That rules out being allowed to ask which direction it is to tighten a screw in a drill chuck then :wink:

I retract my comment about screws.