Talk:GE AC4400CW

QNSL

The list of owners needs the addition of the Quebec, North Shore and Labrador, who now have 12, numbered 415 to 426. Qualicum

 Done --DP67 (^talk/_contribs) 13:10, 17 December 2007 (UTC)

AC Lightning bolt

I've seen quite a few AC's with lightening bolts painted on them. I was just wondering if this was a common enough trait among all operators or just CSX, NS, and Conrail. MY reason for asking is that I had thought of adding it to the article as a common spotting mark if it is indeed common.

--DP67 (^talk/_contribs) 13:10, 17 December 2007 (UTC)

Only CSX uses lightning bolts to distinguish their AC traction locomotives from their DC traction locomotives. Conrail used the words "Radial AC" (to denote both the radial steering trucks and the AC traction motors) along with a sine wave. NS eventually continued that tradition with their ex-Conrail SD80MACs, but I don't think they've done anything similar with their ES44ACs, which are the only other AC locomotives they own.

—BMRR (talk) 22:50, 6 April 2009 (UTC)

AC/DC=AC?

Just curious.. I've never quite figured this out. Alternators produce AC from the start (that's how they got their name). To get DC from an alternator you have to rectify it. On AC loco's they all rectify the AC to DC and then invert the DC back to AC. Yet they say it's more officiant.. Does anyone know why they convert then reconvert back again?

--DP67 (^talk/_contribs) 13:10, 17 December 2007 (UTC)

I'm not an expert on this, but I think it is desirable to power AC motors from a DC source due to the use of digitally controlled inverters. Being a DC source, there's no fixed source frequency to contend with; the inverter's output frequency is variable depending on the speed and torque the motor needs to produce. As for the prime movers spinning up AC vs. DC power, that depends on factors such as commutator maintenance and energy (heat) loss of more silicon for rectifiers. n2xjk (talk) 16:44, 17 December 2007 (UTC)

On a DC generator, the excitation is applied to the stator, and the output is from the rotor, thru the commutator and brushes. On an AC alternator, the excitation is applied to the rotor thru brushes and slip rings, and the output is from the stator. By using an alternator, the possibility of a disastrous commutator "flashover" is eliminated, providing greater dependability and power handling capability. As stated above, DC is preferable to AC as input to the inverters. Wuhwuzdat (talk) 23:19, 6 April 2009 (UTC)

Tractive effort?

It says in one place that this model is available "with 20,000lbs extra to increase tractive effort". Surely "tractive effort" is a measure of force exerted, like horsepower or drawbar pull even, not just a term for "how good the loco is at pulling stuff". The only thing that adding extra weight would do is increase adhesion. Unless adhesion is a factor in the tractive effort formula, which would seem weird. I could think of a better word for the general overall pulling power.

64.223.161.223 (talk) 04:47, 5 September 2019 (UTC)

Why the rollback?

Union Pacific 4014, why did you rollback the edits I made that added information to the citations? Slambo (Speak) 14:34, 26 June 2020 (UTC)

Alphabetical listing

It would be appreciated if the name where put in alphabetical order. Any export locomotives need to be listed below the North American railroads. Original owners only. Not current operators. If SPC Rail Group bought 32 SD70M's, that doesn't mean that that company is an original buyer. Even though Santa Fa is what was seen on the side of the locomotives, the name needs to be listed as AT&SF, then BN and BNSF after that.

Eric Erie Ericerie (talk) 01:27, 30 October 2023 (UTC)