CIM Motor Sacrifice

[Ether]

Originally Posted by Aur0r4

@Ether

Perhaps I am wrong (and there's always an opportunity to learn) but we went through the specs last year and we were unable to find anything that showed that the 18V version running at 2/3 the nominal voltage performed better than the RS-550 at nominal.

Here's the specs for the 775-18 operating at 12 volts:

M7-RS775-18-AT12V.pdf

[nickcvet89]

We are considering this

AM Planetary with 2011 Fisher Price KOP Motor Installed (am-0822)

Performance Data:
Input voltage: 12 volts
Stall Torque: 1.4 ft-lb
Free speed: 5500 rpm
http://www.andymark.com/product-p/am-0822.htm

Specs are really close to a regular CIM motor

[magicole]

Originally Posted by Garrett.d.w

Back to OP, this year we are placing a BB 775 with a CIMulator gearbox in places where a CIM would be normally used.
You could do this on your drivetrain or anywhere else really. If you are going to build a ball pitcher, I would use the 775s and keep the more powerful CIMs for drive.

this is a great idea. hopefully it will keep our weight and power consumption down.

[Ether]

Originally Posted by Garrett.d.w

Back to OP, this year we are placing a BB 775 with a CIMulator gearbox in places where a CIM would be normally used.
You could do this on your drivetrain

Some numbers to consider:

CIM stalled at 60* amps generates ~325 watts of waste heat

775-18 stalled at 60* amps generates ~500 watts of waste heat.

Has anyone run a test to see how long a 775-18 can be stalled at 60 amps before it smokes?

EDIT: see this post: http://www.chiefdelphi.com/forums/sh...&postcount=237


*per the datasheet, 40 amp MX5 can sustain 60 amp for up to 47 seconds

[Mara]

Our team believes that four CIM's is essential for our drive train. We need our most powerful motors to get over the bump. We'll be using some other motor for our shooter. Perhaps a bane bots or fisher price.