Mad Monkey Brushless RTR, NiMh or Lipo only ?

[Dandare]

A mate has just bought one of these, i assumed it could be run on either NiMh or Lipo's, most sellers state either but Modelsport state "Requires lipo battery & charger to operate (cannot be used with NiMh batteries)"

The esc also has a Tamiya connector fitted.

Could someone confirm for me what the situation is with this kit & the batteries which can be used in it ? I said he could use my spare NiMh batteries until he gets some Lipo's...

Thanks, dan.

[kaylon]

Well..according to the 2012 catalog the Mad Monkey Brushless RTR is fitted with the Sirius max 2 ESC (141000270) which again according to Ansmann can use 4-10 cell NiMh or 2-3 Series Lipo. The ESC is listed as Brushed...but it's the one in the Brushless RTR, I've checked several times.

ESC link

Expand the 'more info' on the Sirius Max 2

It's basically a modified Modelsports (Mtronics) Sniper RV-12 assault, which I have and yes it can use both and has a fail safe cut of at 3.1v for Lipo's I think.

Edit: Umm..I'm not convinced that the Sirius Max 2 is the one in the RTR, but they don't list by part number any other ESC so it's hard to find out However ALL of the actual Ansmann Brushless specific ESC can still take both types of batteries... 'shrugs' ....

J

[racingdwarf]

Best errr on the side of caution if using a lipo unless you can find out 100% it has cutoff,as soon as you see even the slightest drop in performance stop!, back when quite a few of us we using lipo with brushed ESC's it was quite easy to go for to long. Thomas discharged a couple of lipos to low and a lipo charger will not charge them again.there is a trick to get them back....but it's a bit spicey

[Dandare]

Point taken regarding using lipo's, voltage drop etc (although the guy who reviewed this in Radio Race Car thought it was ok & was using his lipo's)

I'm more concerned whether there can possibly be a problem using MiMh batteries with this esc as thats what we were gonna use to get going ??

[VintageRacer]

I can't imagine there being a fatal problem. The voltage of nimh is lower. The only problem I can see is if the ESC has lipo cutoff that can't be disabled, it might then cut off prematurely for nimh.

[Dandare]

Originally Posted by VintageRacer

I can't imagine there being a fatal problem. The voltage of nimh is lower. The only problem I can see is if the ESC has lipo cutoff that can't be disabled, it might then cut off prematurely for nimh.

That's what I wondered, so if the cut off was set for say 3.1v per lipo cell then it'll just detect when a NiMh battery drops to 6.2v ??

Would a 4000 NiMh battery last a 5min race before dropping to 6.2v though ??

[Robbiejuk]

Yeah they would but nimh discharge differently to lipo. What you will find when you boot it off the line the motor pulls so much voltage temporarilary that the Lipo cut off will kick in, so the car will start to move and the suddenly stop. The only way to get it going again is to feed the throttle in slowly.

[VintageRacer]

We are generally using around 1600mAh in a 5 minute race, but that is a with a fairly tame motor (17.5t) so 4000mAh should be plenty.

As Robbie has said though, when under heavy acceleration (at the start or out of a corner), the high current drawn will cause a significant temporary voltage drop (due to the internal resistance of the cells if you're interested) which may cause the lipo cutoff to trigger even near the beginning of the race. The only way to find out for sure would be try it.

What is your reason for wanting to use NiMh to start with?

[Dandare]

Originally Posted by VintageRacer

What is your reason for wanting to use NiMh to start with?

Initial budget really, I've offered the use of my NiMh's & charger as I don't use them, until he gets lipo's.

What I'll suggest is to try a NiMh, purposely run it low & to see if the ESC low voltage cuts in if it does then we'll know it has one, if not we'll look into the possibility it had a cut off but is not activated.

[VintageRacer]

Fair enough if the Nimh are already bought, I reckon it would false economy to buy them new now.

[Dandare]

Well, i've now looked through the enclosed paperwork & on an A4 sheet it states that the ESC can run Lipo, NiCad or NiMh & amongst other settings the cut off can be turned on & off but the default setting is on/Lipo use.

Problem now is that there is no programming card included & no instruction as to whether the ESC can be programmed using the tranny etc. I can't find anything about where to get a card either...

Now what, lol ?

[Robbiejuk]

Picture of the Speedo? Just trying to work out which one you have?

[Dandare]

Originally Posted by Robbiejuk

Picture of the Speedo? Just trying to work out which one you have?

Here's the Modelsport Ad with 2 of the pics showing the ESC: http://www.modelsport.co.uk/ansmann-...&ChassisID=823

I've just emailled AR-UK asking if there is a card available, the Dec 2011 issue of Radio Race Car has it reviewed stating that the sample kit came with a programme card. Hopefully they'll come back with some helpful info !

This is the sheet that came with it:

[Robbiejuk]

Hmm yeah looks like from the programming instructions for the programming box I have for my xirius pro. Should have come with a programming card. It has a little programming card that uses jumpers to change the settings. There is also a little programming box you can get with a digital display you can get makes it a lot easier to change settings.

I have the digital box so I never use the card that came with the Speedo so I can lend you the programming card if you want to borrow it let me know Dan.

[Dandare]

Thanks for the offer Rob, as it's not my kit i'll have to let it's new owner decide which batteries he's gonna use, if he still wants to use my NiMh's we'll give them a go on the current esc settings & see whether it keeps cutting, maybe then i'll take up your kind offer.

Interestingly even the basic card you have i can't seem to find for sale on it's own anywhere, does seem strange to actually include a list of different esc settings but no card or even a clue as to how to adjust them

Cheers again

[Robbiejuk]

Yeah, unless they are bundling them with the programming box now?

P.s. better ballrace it before he races it. I was shocked when I took apart a brushless rye madrat for one of our club members and discovered it had come with bushings, even the gearbox wasn't ballraced, including the small bearings in the diff!

[davidmog99]

Ansmann rtr instructions dont always relate to the equipment they supply. I tried programming the speedo on my car using the manual for my 1/8 with no success. Was brand new.
I googled the code i found on the speed controller and found it was a completely different model. I am not complaining it is a much better speedo and i can now use 4 cell with no problems even though the ansmann manual said 3 cell.