for HOT WATER: You told me that the resistance was either 0.66 or 0.86 ohms. As I continue my education in this area, I have another Q: Do those values refer to a single traction motor/generator and its associated grid resistor? I.e.; for a 6-axle diesel, there would be 6 of these circuits, right?
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for HOT WATER: You told me that the resistance was either 0.66 or 0.86 ohms. As I continue my education in this area, I have another Q: Do those values refer to a single traction motor/generator and its associated grid resistor?
Nothing really to do with a "single traction motor/generator", but each "box type" grid resistor, as they are all in series with the traction motor armature circuit. The main generator of the unit supplies low voltage/high current thru the traction motor fields, all connected in series, which then cause current to flow out of the traction motor armature circuit and into the grids (the load).
I.e.; for a 6-axle diesel, there would be 6 of these circuits, right?
No. Just like a four motor unit, the six motor unit has all the traction motor fields connected in series, and all the traction motor armatures connected in series with the grids. Obviously a 6 motor unit will have many more grids plus 2 DB grid blowers.
Thank you. I've been pondering these issues for some time now, and have more, detailed, issues that I'd like to discuss with you. But, I think it would be preferable to do this off-line; ie, via email. I hope you agree.
Please send your 'yes' message to me via: pgresho@gmail.com.
Sorry, not interested.
I'm disappointed; so I'll post my next Q's on this forum:
1. In your 2nd sentence, I assume by "unit" you are referring to the locomotive....Correct?
2. This sentence also implies that the main generator is NOT electrically-disconnected when applying the dynamic brakes. Is this correct? I thought it was 'out of the picture' during braking.
2. This sentence also implies that the main generator is NOT electrically-disconnected when applying the dynamic brakes. Is this correct? I thought it was 'out of the picture' during braking.
By varying the current into the traction motor fields from the main generator while the traction motor armature is connected to the dynamic braking resistors you can vary the amount of dynamic braking effort the traction motor provides. More current into the field = more dynamic braking provided the motor is rotating. Hot Water can tell you about the dynamic braking effort vs speed. Read up on alternators/generators/electric motors. This should help you answer your own questions.
Thanks, Matt. In reference to....."Read up on alternators/generators/electric motors.....": I AM doing that, which prompts me to ask if you are an EE; and if you would mind some off-line discussion that Hot Water declined?
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