AC vs DC traction motors?

[Rich_S]

Believe it or not, the discharge circuits, I believe, are not checked on a regular (92 or 126 day) basis.

That is true. In fact the railroad that I work for only does 92 day inspections on 26L air brake equipped locomotives. All other locomotives are now on a 184 day inspection cycle. If the locomotives are not showing faults for the discharge circuits they are not looked at.

[Rich_S]

I'm waiting for one of the discharge circuits to fail. It should make for a fantastic show

It's now a rule that before any AC motors are changed on the motor drop table, they have to be checked and manually discharged. Hopefully we can keep from killing someone as long as this rule is followed. On a side note, are you a electrical engineer? Maybe working for one of the two big name locomotive builders?

[dfcfu342]

On a side note, are you a electrical engineer? Maybe working for one of the two big name locomotive builders?

That would be a no and a no. I would hope with the large gaps in my knowledge I would not be designing locomotive systems

[Rich_S]

Absolutely fascinating stuff!

I graduated with a degree (B.Sc. Hons) in Electronic & Electrical Engineering, but I haven't done anything even remotely related to motors and circuits since then (I was bitten by the software bug in my second year). This discussion brings it all back! Perhaps I should have stuck with the electrical engineering side.

Might I suggest that someone write an article on this for RSC's Engine Driver? You could collaborate on it - maybe one could write a draft and others could review it. Just an idea.


Mike

Mike, I tried computer programming as a profession, Cobol and C, for a large company that creates software for doctors and hospitals. As time went on the dead lines and stress became more than I could take. I was actually relieved the day my job was eliminated due to downsizing. Now I actually get paid to work on locomotives, plus I get to move them around and test them on our test track. It's not all peaches and cream, it's like a lot of jobs you have good days and bad days, but the stress level is 75% less than what I had with that programming position. Those of you still in the computer industry, I feel for you.

Rich S.

[BillS]

Interesting; when the things you enjoy and love become your way of making a living, sometimes it's not the bowl of cherries you thought it would be.

I've been early-retired, for almost 20 years now, and near the end of my career the way companies do business changed. I was, "down-sized", out after 20 loyal years. They wanted to run, "lean and mean", and get more done at the expense of their remaining employees. Then, the guys in the "ivory tower" wonder what the problem is? Sometimes companies forget that the most important asset that they have is the people that work for them. There's no reward (and I don't mean just money) with many companies anymore. They don't care whether you do a good job or a half-as___ job

(Sorry, after reading this entry, and Rich mentioning, "feeling sorry for the guys in the computer business", it kinda reminded me of my working days. Not blaming you Rich, it just ,"struck a nerve", so-to-speak).

Okay, back to trains!

BillS

[mrennie]

Interesting; when the things you enjoy and love become your way of making a living, sometimes it's not the bowl of cherries you thought it would be.

I've been early-retired, for almost 20 years now, and near the end of my career the way companies do business changed. I was, "down-sized", out after 20 loyal years. They wanted to run, "lean and mean", and get more done at the expense of their remaining employees. Then, the guys in the "ivory tower" wonder what the problem is? Sometimes companies forget that the most important asset that they have is the people that work for them. There's no reward (and I don't mean just money) with many companies anymore. They don't care whether you do a good job or a half-as___ job

(Sorry, after reading this entry, and Rich mentioning, "feeling sorry for the guys in the computer business", it kinda reminded me of my working days. Not blaming you Rich, it just ,"struck a nerve", so-to-speak).

Okay, back to trains!

BillS

I could write a novel about where my career went over the last 30 years (moved country, founded a company, wrote software, single-handed, for instruments onboard science satellites, eventually fired myself from my own company, after it had been taken over, rather than be forced to fire other people ...). Anyway, now I'm much happier at home making models for TS, and so ... back to trains.

Any thoughts on writing up that article? I'm sure it would get published.

[GSkid]

I'm waiting for one of the discharge circuits to fail. It should make for a fantastic show

It's now a rule that before any AC motors are changed on the motor drop table, they have to be checked and manually discharged. Hopefully we can keep from killing someone as long as this rule is followed. On a side note, are you a electrical engineer? Maybe working for one of the two big name locomotive builders?

I remember having to discharge tube TVs years ago before working on them. We had a huge discharge probe that had chunks nicked out of it from arcing events.

What do you guys use to discharge those AC motors?

I kinda hope I live to see superconducting AC traction motors on locomotives. So far they've only been demonstrated in ship propulsion motors.

[Rich_S]

What do you guys use to discharge those AC motors?

It's a long fiberglass probe with a metal tip and a grounding cable attached to the metal tip. It also has a hand protector that kind of reminds you of a fencing sword. So far the crowbar circuitry on the locomotives have been working, so I haven't had to use the grounding probe yet.

[GSkid]

It's a long fiberglass probe with a metal tip and a grounding cable attached to the metal tip. It also has a hand protector that kind of reminds you of a fencing sword. So far the crowbar circuitry on the locomotives have been working, so I haven't had to use the grounding probe yet.

Ok. I know what kinda fiberglass probe you are talking about. I've seen them used in high voltage test laboratories to induce arcing events to help simulate a lightning strike on outside electrical equipment to design them more resistant to failure.. Also it's similar to the fiberglass poles high voltage power line workers use to engage those clasp latch-like switches on your residential power lines.....but they don't usually have the fencing sword guard on theirs though.

I learned to only fix consumer electronics back in the day, but I really respect power line men and the dangers they face. A guy I know worked on that stuff and told me of a friend of his that died on the job. There were these huge high voltage transformers in an enclosed concrete cinder-block room that was fairly dark inside. One of them was leaking coolant or something. There was a pool of it around the base of the transformer. The guy didn't see it and stepped in it. The voltage and current was so high that the guy literally vaporized and left a silhouette of himself on the adjacent wall. It looked like the guy's shadow. Scary stuff!