Western Railroad Discussion > A question on U28B notches

I've heard that the old GE U28B had 16 notches in the throtle. Since this model never came to Brazil I would like to know if it true or not. Does somebody have pictures of that throtle?

Pedro

Posted from Android

Pedro Rezende
Vespasiano MG,

pedrop Wrote:
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> I've heard that the old GE U28B had 16 notches in
> the throtle. Since this model never came to Brazil
> I would like to know if it true or not.

True. The U25B had "half notches", where the "half notch" did NOT increase engine speed, just excitation. Thus giving "16 notches".

Does
> somebody have pictures of that throtle?
>
> Pedro
>
> Posted from Android

The Western Pacific's U30Bs had 16-notch throttles. If you pulled the handle back all the way it was easy to smash your hand between it and the brake valve.

I can only make this photo show up sideways, but this is a photo out of the U-25 operator manual, U-28 would the same, as were Santa Fe GE's of the era. Not a very good close up of the throttle, but it has is long, and had a long swing. It had the main notches marked, with a half notch between each number.

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If I recall correctly, in Trains "All GE" issue, Jeff Schmid did a story about operating the former U25B demonsrators the Frisco bought and has some details on operating the 16 notch throttle, and MU ing it with EMD units.

Also you could not see the notches at night because of the placement of the light on the control stand.

try this

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Here are three photos of from a GE's operator manual from 1968 that included U23's, U30's and U33's. No specific
mention is made in this manual of U28's but given the appearance of the other Universal series locomotives I suspect
the 28's had the same controls. 

As the drawing shows, the throttle had IDLE and eight 'major' and eight 'minor' positions or notches and as HotWater has noted
there was no increase in engine speed, just excitation, while advancing through the 'minor' positions. The throttle handle, 13 on the
close up, controlled both tractive effort and braking effort depending on the position of the 'selector handle', 12 on the close up. 

The 'selector handle' had five positions as shown on the drawing and can barely be seen in the close-up.

I had a personal and up-close near disaster one evening when yarding a train. I had one of these 5 position 'selector handle' GE's
on the point and after the last switch into our destination track had been passed I, mistakenly, didn't look at my load-meter as my 
speed began to rise. Thinking I was still in dynamic braking and realizing my speed was continuing to rise I added to my error by 
moving the throttle handle even more toward the #8 position. What I failed to note was that I had failed to move the 'selector handle'
all the way to the 'Forward Braking' position after using a light application of power in the 'Forward Motoring' position to start the train. 
TO's member JGFuller was there, saw the error of my ways, and thankfully called a warning on the radio. Thanks again, Jack!

Charlie
 

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FWIW, Trip Optimiser (only in GE products) will run half throttles. The trailers still are in full notches.

It likes to run up hills at notch 7.5, while
Your trailers and DP’s are in 8.

But we are saving fuel!

Posted from iPhone



Edited 1 time(s). Last edit at 07/20/20 20:51 by MP683.

CEW: Flattery will get you everywhere! Thanks!  -- JGF

Thanks to all that replyed this post. Very good photos, drawings and experiences lived by railroaders with this strange notch device.
I have another question. I am not a engineer,just a railfan that wants to learn more and more eith the railroaders. So, when we say the half notch just excite the system, what can I understand? To excite the system means to give more Amperes to the next notch?

Posted from Android

Pedro Rezende
Vespasiano MG,
https://youtube.com/c/minasgeraisrailways1

pedrop Wrote:
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"..... So, when we say the half notch
> just excite the system, what can I understand? To
> excite the system means to give more Amperes to
> the next notch?

Persons with knowledge of this subject read these posts and hopefully will contribute the answers you're seeking. 

I will add something that I forgot earlier. When using dynamic braking the so-called "notches" felt by the "throttle handle"
are not present, that is the movement of the handle is smooth and without the 'stepping' action felt when advancing or
reducing the handle through its range of motion while in "motoring".

Charlie

 



Edited 1 time(s). Last edit at 07/21/20 11:06 by cewherry.

Was this the same situation when Don Holderman and two others died on Cuesta when Don thought he
was in dynamic but was under power.  This was a lite help helper returning from Santa Margarita to SLO.

MP683 Wrote:
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> FWIW, Trip Optimiser (only in GE products) will
> run half throttles. The trailers still are in full
> notches.
>
> It likes to run up hills at notch 7.5, while
> Your trailers and DP’s are in 8.
>
> But we are saving fuel!
>
> Posted from iPhone

UMm, watch the load meter. It's not loading any more. Just TO preparing to advance the throttle.

Much better, thanks.

Posted from Android

Still have my old Form 2503 book, here's the page for U28 & U30's on the Santa Fe. Also some of these old GE's had a "1-5-8 speed schedule". "With throttle in notches 1, 2 & 3, medium speed (former notch 5) is obtained, Run 4 and above, engine is at full speed."

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