ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 263 guests, and 17 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#47725 01/25/05 10:04 AM
Joined: Mar 2002
Posts: 360
T
Member
Here at the railroad we have a drop pit. A section of track that is supported by 4 screws that are turned by this complex arrangement of gears and shafts. Takes about 20 minutes to drop the 10 feet or so to the bottom. The thing is run by a 25 hp motor. The motor is started by the item in question.

To start this thing the handle is moved to the start position, and when everything is turning, about 3 to 5 seconds or so, then you move the handle through the "off" into "run", prop the stick in it, and watch to make sure that you have the end of the car supported and you didn't forget to chain up the end of the truck.

My question is, The "starter"'s nameplate says that it is a GE starting compensator, # CR1034 K1B. It has an oil bath in the bottom, it's ancient.

We are looking to replace it with a more modern starter, (don't ask why) and I would like to know how this one works, and I can't find anyone who knows.

Does anybody here have any experience with these things? How does it work?

Thanks

TW

By the way, nobody knows why railroad signal hardware is 1/4-24. [Linked Image]

Joined: Jul 2001
Posts: 599
J
JBD Offline
Member
The old manual compensators, that I know of, were basically manually controlled autotransformer style reduced voltage starters. Oil switching was used to control the arc and provide insulation in order to reduce the size of the switch.

Instead of timing circuits and magnetic contactors, the transformer taps were controlled by the operator. The faster you moved the handle the shorter the acceleration time, to the point were you could have almost no soft start at all. It was also possible to not move fast enough causing the transformer to over heat.

Joined: Mar 2002
Posts: 360
T
Member
I kinda thought so. There is a lot of moving machinery to get rolling in this thing. So a soft start, or a reduced voltage starter would be just the ticket. now to get the price past the boss's nose without him having a stroke. [Linked Image]

TW

Joined: Apr 2002
Posts: 2,527
B
Moderator
 
TW — I agree that it sounds like a manual-autotransformer motor starter. The old Allen-Bradley versions also had a bell that, during starting, sounded after rotor speed increased to normal—signaling the operator to transfer the “slot machine” handle to the running position. [In mills in the northwest. oil-immersed contacts minimized arc-induced sawdust detonation.]

Modern autotransformer magnetic starters have taps at 50, 65 and 80% of line voltage, to allow inrush-current and starting-torque matching.

[The "prop stick" muat have been a custom accessory.]

Joined: Mar 2002
Posts: 360
T
Member
Yup, the prop stick was this polished (from use) mahogany, (a cut off from some of the stuff we build the cars out of) just the right length. Nobody wanted to stand there and hold the thing for the 20 minutes it took to go from one end of the travel to the other.

I think I've found something that will work, for a price that won't have the boss's hair falling out.

TW


Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5