Bosch Motors

Hi,

Last year there was a guy selling loads of bosch motors on ebay. They looked like the 12V 400W ones so i bought 4. I have finally got round to thinking about making a new robot and was wondering if anyone else bought some and have tried them out in their robot? I plan on using all 4 for drive on a 6 wheel low robot with a electric flipper.

I guess they are going to be current hungry, but the torque will be useful....

Any idea what controller would be suitable? I used two pro 120s in supernova, but they were a pain to use. i am guessing controller technology has improved?

Suren

Hi Suren

We are using them at 24v in Iron-awe 3 with a roboteq with no problems although I think John Lear had some problems with them at that voltage.

Rob
http://www.iron-awe.co.ukwww.iron-awe.co.uk

heya
I also bought 4 of these motors check my profile for what I was going to use them for. I have done lots of reasearch and sadly I am a bit limited on what I can actually use these motors on.
First off the motors move quicker in one direction then the other. No one gave a definate answer on how to correct this so I just turned one of the motors around and used that side.
As for controllers I origanally wanted to run the motors on 24volts. However if you double the voltage you quadruple the watts. This would ressult in huge current draw. I would need a controller to hand 3.2kw which is not going to happen. Some people have blown sidewinders even just running one motor on 24volts.
So I was just going to run the motors on 12volts.
However there are few controllers out there which actually run on 12volts. Wotty and sidewinder are both 18volts.
Only the robot solutions rs80d would be close and of course 4qd 12volt ones. Though I had issues modding a 24volt one to go to 12volts
However I had a linear actuator in the robot which needed to be ran at 24volts or I have a super slow weak weapon. after all this hassle I have just decided to get some bosch 750.

I am going to put one of these in a feather at crank it up to 24 volts and use it as an axe on bang bang controlle.

I do however have one last test which is to try and run a single 400watt on a modded electronize 40amp controller. Il let you know how that goes.

Another option is to try and run them on those crazy no limit tiny racing car speed controllers. Which suposidly can handle 400 amps. However nobody has any experience with them and I have my doubts. The wiring is tiny and it uses those racing car conectors. Which fuse together when 30 amps is passed through it. Wouldnt like to see it at 400!

Sorry to put a bit of a downer on you plans.

marco I found that rotating the magnets by a few mm sorts out the different speed problem. If you look at the mounts you see that the magnet retainers can be put in 3 different slots in the casing (all beside each other). They come with the retainers in one of the side slots. Putting them in the middle one seems to sort it but its a bit fiddly to do.

I have happily run a bosch 400 on a 16:1 ratio with a small car speedo (http://www.howesmodels.co.uk/RadioControl/viewProduct.php?ProdID=1605http://www.howesmodels.co.uk/RadioCo...hp?ProdID=1605). I ran a computer fan over the speedo and it got warm but nothing too bad. I wouldnt advise running without some additional cooling.

We run the Mag S28-400 on 24V with a 36V battery by adjusting the transmitter range. There is no reason to stop you using a higher battery voltage than what you run the motors on as long as the speed controllers output is limited to suit. There are of course some disadvantages if you set the system up wrong you could put more power through the motors than they can handle but at the end of the day if the current limited controllers (our drive current limit is turned off in big nipper) have a reasonable current limit set then you cannot give the motor too much power, but of course performance will suffer.

Im no electric whiz, but just a few things to add which maybe helpful as they were to me..

Well Garrys right u can rotate the magnets to sort the speed prob out.

The Sidewinder will attualy work at 14.4v
Just make sure the batteries can give the current needed so the voltage does not drop too far.. i think i attualy got my sidewinder to work down to 12.5v...
Well im going to run 2x bosch 12vs on 14.4v on my sidewinder.

There is a mod you can do to the sidewinder to run at 12v, but it by-passes a few safetys which then means if you have a dodgy battery, it can take out the brain side of things.. but run it at 14.4v and your cool - only extra few cells. Granted if your using SLAs your stuffed.

But Running the bosch 400 watt motors at 14.4v is no big who har... even running the 12v 400 watt motors at 18v on a sidewinder would be a decent wattage and keep the sidewinders happy.

Oh the other thing - yeah its a good idea to have a bigger battery pack eg 36v but use the Radio kit using dual rates or end point ajustments etc to limit the voltage to 24v or something - but be warned you do put more stress on the speed controller doing that than just using the correct voltage battery... speed controllers will get very warm fast doing that. I did it and things do get warm fast, i was advised against it.

Mr Stu

You are absolutely correct there Stu. Speed controllers, all speed controllers are the most happy at 0% or 100%, and have a hell at 70%. They heat up like a bbq.

Yep your right, forgot to mention that, most speed controller do tend to run hotter used this way and so do the motors.

all i can say burnt 3 out in 5 mins DO NOT RUN THESE AT 24V may be ok on 18 or so dont wish to try

at 10:1 ration gearing

if i ran two motors in series on each side?

thats a point if you ran them in series on 24volt would they be ran at 12volts each?

Yes.

But the motors will have double the current being pulled through (eg each motor is pulling 40amps, then the total 80amps must pass through each motor). So expect them to get warm.

Does that mean the speedo will have to handle more amps?
So it would still be best to get a 12 volt speedo and run the motors on a single 12volt battery pack in parrelel.
Or no difference running them on 24volts with the motors being in series?

some errors in the above advice, wont go into it all, but to save you blowing things up, although they do pull 12v each from 24v total supplied if equally loaded, do not lock a wheel, or something unwanted happens to the other.

I currently run...

Edgehog, 100kg, runs 2x12v 400W motors for drive, a single hawker 12v SLA battery, sidewinder controller, no problems at all.
has run 18v and 24v, without problems, but Edgehogs gearing is wrong for 24v, so it pulls too much current for my liking.
Speed at 12v is slowish but ok, 18v is good, 24v is a bit silly.

If you want any info on the sidewinder with bosch 400s Suran, drop me an email and I can give you more details about Edgehog.