|
|
Post by oliver on Jan 10, 2006 20:45:17 GMT
When a 96TS pulls into a station what is that funny noise... Dooooooooo Dooooooo Doooo Doo Beep Beep Beep Is it: increasing break pressure decreasing motor levels some sort of gears  p.s. Maybe those D's should be Z's ;D  |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 10, 2006 20:49:34 GMT
It's the gearing. Don't ask me to be technical though!
Sam
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 10, 2006 21:13:15 GMT
Oooh i LOVE those noises ;D
Correct me if i'm wrong, but the 'beep' s are the brakes.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 10, 2006 21:58:49 GMT
The noise is from the gate turn off thyristors (GTO) which control the power to the motor. It's a form of "electronic" gearing, rather than mechanical gearing.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 10, 2006 22:45:14 GMT
The traction package on the 96ts is in fact older than thier cousins; the 95ts. Traction package on the 96ts is similar, if not the same to the NR Networkers running in North Kent, and horrid things they are too... Just get a 96ts above 65kph and the units sometimes oscillate and judder oddly.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 10, 2006 23:43:08 GMT
Just get a 96ts above 65kph and the units sometimes oscillate and judder oddly. I never had any juddering units in my time over there, and that was doing almost 65Mph rather than Kph!!  ;D I can't ever remember a beeping noise though. |
|
|
|
Post by graham on Jan 11, 2006 11:19:58 GMT
The "new" switching motors using IGBTs or GTOs are actually quite good and should give a smoother application of power, and thus allow greater acceleration without upsetting passengers.
Compare the new Electrostars and the old slam door train on Southern for example.
However - the earlier ones such as the Networker family and the 96TS are very noisy. Though I remember being very excited about the futuristic noises when I was little and they were introduced.
|
|
|
|
Post by traveller1030 on Jan 11, 2006 11:27:19 GMT
However - the earlier ones such as the Networker family and the 96TS are very noisy. Though I remember being very excited about the futuristic noises when I was little and they were introduced. When it comes to the Notworker (or indeed the '96), some of us never grew out of that... ;D - the excellent timbral qualities do it for me. Post Script: I never had any juddering units in my time over there, and that was doing almost 65Mph rather than Kph!! ;D Oh to have drivers like you back on the Jubbly... I remember when the JLE first opened how some of the drivers absolutely caned it in the new tunnels - journey time does seem to have increased lately. Must admit if there is supposed to be oscillaiton in the saloon the only I remember is between a certain band of speeds, possibly to do with the gearing? I remember MkII Fiestas and MkIII Escorts (crude example I know, but the closest I can think of) having the same problem from about 66-76mph. Shook about like anything trying to keep to National Speed Limit, get it to 80 and all is normal again... work that out. |
|
|
|
Post by q8 on Jan 11, 2006 12:12:26 GMT
The "new" switching motors using IGBTs or GTOs are actually quite good and should give a smoother application of power, and thus allow greater acceleration without upsetting passengers. Compare the new Electrostars and the old slam door train on Southern for example. However - the earlier ones such as the Networker family and the 96TS are very noisy. Though I remember being very excited about the futuristic noises when I was little and they were introduced. I know what a GTO is, but what's an IGTB? |
|
|
|
Post by Dmitri on Jan 11, 2006 12:49:35 GMT
|
|
|
|
Post by q8 on Jan 11, 2006 12:56:16 GMT
|
|
|
|
Post by russe on Jan 11, 2006 13:27:04 GMT
I remember MkII Fiestas and MkIII Escorts (crude example I know, but the closest I can think of) having the same problem from about 66-76mph. Shook about like anything trying to keep to National Speed Limit, get it to 80 and all is normal again... work that out. Not uncommon with many motor cars of that era. Slight imbalances in the wheels cause them, in conjunction with the car's springs, to vibrate at what is called their 'resonant frequency'. This natural system oscillation will develop towards a certain speed, and die away again after that speed has been exceeded. A more complex, but essentially similar in principle, situation is happening in the transmissions of the 95TS. Good spring damping design will mitigate the effect. Russ |
|
|
|
Post by cdr113 on Jan 11, 2006 19:31:50 GMT
talking of these noises, are the 96 jubbly and northern line stocks related? i've noticed the northern stock doesnt make the forementioned noises....
|
|
|
|
Post by tom2506 on Jan 11, 2006 20:25:12 GMT
The 95 and 96 share the same body shell but have different types of motor (Insulated Gate Bi-polar Transistor power electronics instead of Gate Turn-Off Thyristors).
|
|
;D
