Where does 540 come from ?

[FilthyPierre]

Anybody know what the "540" in 540 motors means ? Is it the length of the armature laminations or something like that ? We're now seeing the 550 size motor in the E-Maxx, and some of the smaller cars use 380 size motors, so I guess in general terms what does the number refer to ??

[RichieRich]

The numbers refer, I guess "loosely", to their length. So a 540 motor is roughly 54 mm long.

[prime]

I always thought it had to do with the number of miliwatts the motor was rated at. Any EEs here to clear this up?

[SirSpeedy]

Hmmmm....

Not sure about the 540 rating...

I do know that they are also refered to as "05" motors. That is a horsepower designation. 0.05 HP.

[Aussie_Man]

540 mean the can of the 540 motor is 54mm long. Same thing with the 550 motors, they are 55mm. And with 380, they (you guessed it) 38mm. You can get other motors like Speed 600's from some shops, they are designed for planes and are fairly big (60mm, LOL). Hope that explaned it. About the 05 bit, I have a set of rules (which are IFMAR standards) saying all mod motors must have 05 sized displacement, 36.02mm in diameter, 53mm maximum length (excluding bearing housing and shaft), shaft dia. .125inch.

[FilthyPierre]

Thanks I figured it had something to do with length. Interestingly the can of my P2K is only 37mm long, 40 if you include the bearing housing. No wonder those new Trinity 550's for the E-Maxx look so **** big by comparison. Makes you wonder though who decided on 54mm - it can't have been an (non-metric) American http://www.rccaraction.com/ubb/smile.gif
FYI Prime - power = volts x amps, so if 540 was the power rating in milliwatts, that would be 0.54 watt, which is way under the power used by the motor. Say it's drawing 5 amps at 7.2 volts (flat out), that's a power draw of 36 watts.

[2 DA MAXX]

No sorry,(unless you skrunk your P2K???? http://www.rccaraction.com/ubb/confused.gif ) My P2K IS 54 mm long, if you measure the traxxas stinger motor from end of motor case to the other end of the motor case(excluding the shaft) it also is exactly 54 mm long so yes a 540 motor is 54mm long! Mr. MAXX

[ammoace]

Man I learn something every time I log on to this BB. I always thought that the 540 referred to converted CCs or CID. I guess someone FINALLY applied the "K.I.S.S." principle.

[JP]

KISS -

Keep It Simple, Stupid.

[rvrrun]

KISS -

Keep It Simple, Stupid.

...and here I thought it was another charming reference to bygone 70's rock bands.

MS