9 motors too much?
 

So for most teams its "panic now" time and it just really hit me that my team is using 9 motors in all for our robot (4 for drive and 5 for the arm). I was wondering if any other team was using 9 or more motors. Because right now I'm having nightmares of of the 120 amp APP CB tripping :eek::ahh::yikes:. I would feel a lot better if there are other teams using 9 or more motors.

Re: 9 motors too much?
 

We are only using 7 (4 drive and 3 for arm/lift). I don't think any of our past designs used any more, some also used pneumatics to supplement that but still...

Re: 9 motors too much?
 

6 on our "little" guy. i wouldn't worry about the # of motors, so long as they were/are being used within design spec. I use that phrase loosely, because FRC is worse than GM/Ford/etc proving grounds.
Also look at which are being used for what. will they all be powered simultaneously?

Design, create, re-design, band-aids, rinse and repeat.

Re: 9 motors too much?
 

We're using 9 this year. In the past we haven't used more than 6-7 so...

- Sunny

Re: 9 motors too much?
 

We have at least 8 (4 for the drive and 4 for the elevator). We're still figuring things out but we may have up to two more, depending on our manipulator.

Re: 9 motors too much?
 

8 motors, and 6 pneumatic cylinders...

...not including the minibot, which has 2 more motors.

9 motors is not unreasonable at all.

Your 120A breaker shouldn't trip, provided all 9 of your motors are properly geared, and you aren't stalling them.

Re: 9 motors too much?
 

That is actually the exact number we are using and they are set up the same way(4 drive, 5 arm).

In my five years in FIRST the most motors that I have every used before this year was 8 and we never had a battery problem and we have never poped the 120 amp main breaker,ever.

Re: 9 motors too much?
 

8 motors and 2 or 3 pneumatic cylinders here.

Re: 9 motors too much?
 

2175 will have at least 8 (6 drive, 2 manipulator) + at least 2 pneumatic cylinders. Minibot deployment is likely going to add another cylinder or 2.

3573 is keeping simple, 5 motors total (2 drive, 2 arm, 1 minibot deployment).

Re: 9 motors too much?
 

We're currently using 7 motors: 4 CIMs, 2 RS775s, and 1 RS550/540 and 3 Pneumatic Cylinders. There is a possibility of us adding another motor or two in the coming weeks, but it's unlikely.

Considering that some teams are going to have 6 motors + in their drives this year, I think you're doing okay.

Re: 9 motors too much?
 

11 Motors and 10 Pneumatic Cylinders.

Re: 9 motors too much?
 

Andre,
Since the 120 amp breaker was introduced, I think I can count on one hand the number of tripped main breakers I have seen or were told about. Of those, I suspect most were due to defective breaker or some other catastrophic failure. The 120 amp breaker can withstand over 600 amps for several seconds before trip.

Re: 9 motors too much?
 

4 Drive, 4 Arm. 3 pneumatic cylinders. Plus Minibot deployment.

Re: 9 motors too much?
 

We have 4 drive motors, and one arm motor, and one claw cylinder. We're working on getting another motor to actuate the minibot. Since it seems to take us a week or two to mount one motor and get it operating, I don't see us having more than 6

Re: 9 motors too much?
 

it is unlikely the internal resistance of the battery is to high to deliver 120 amps unless you physically get a short. we had 10 motors on our 2009 bot and never blew the breaker we ran at 6-7 volts though.