Electronic inertia

[dkvfx]

Still in the middle of building my Skittle Falls layout. I've also discussed here problems with locos passing over points.

As you know there are often moments when your loco loses power momentarily and results in less than smooth running.

Some locos have a flywheel fitted to help with this, but these are, as far as I can tell, practically impossible to retro-fit to locos.

So I've been thinking for a while. Surely there is an electronic solution to this with the fitting of capacitor circuits within the loco. As the loco travels, the capacitor charges. If, for example, the loco finds a momentary deadspot on some points, the capacitor discharges through the motor to continue the travel.

I would imagine this would require electrolytic capacitors which are polarity sensitive, so if you need both forwards and backwards smoothness, then some proper circuitry would be involved.

I also think that because I cant find any mention of this idea online, then there are inherent problems, or I'm not using the right language in my searches.

Any thoughts?

Dunc

[dkvfx]

bus cable running to supply power to known problem areas can also solve this problem too.

Didn't really understand this bit.

The link looked interesting, but with my tired eyes, it looks like its for digital systems. Im old school at the moment, running analogue.

I should have stated that.

I'll check the link out again to make sure I didnt miss something.

Cheers Spocky, Dunc

BTW just did a Google for "analogue stay alive" and got nothing relevant.

[Silver Surfer]

Dcc Concepts have just bought out a new decoder with 'stay alive capacitors' Keep your eyes on their website and you might just find out how big the capacitors fitted to these are.

http://www.dccconcepts.com/index_files/ ... coders.htm

nb. The information for the loco decoders is due to be included on the web page shortly (the owner, Richard Johnson, is on a round the world sales jolly at the moment and is due back mid February - so any time now).

Mike

[Bufferstop]

Didn't really understand this bit. The link looked interesting, but with my tired eyes, it looks like its for digital systems. Im old school at the moment, running analogue.

That's the point - it can be done electronically with DCC because it needs to be installed before the reversing switch, which in DC is in the controller but on DCC is on board the loco in the decoder. Level and clean trackwork, minimum dead spots in pointwork, extra pickups (and wheels with them) and flywheels are the only DC solutions.

[dkvfx]

Check this out:

http://www.electro-tech-online.com/elec ... ertia.html

I started this discussion on an electronics forum and have had some interesting posts.

If you think that it would be really cool to solve this problem, the please check this forum out, if for no other reason to encourage those electronic brains to help figure this out.

Dunc

[Bufferstop]

Dunc the 70s books describing controllers with inertia are a bit of a red herring, I've got them and read and understood them. They simulate the effect of a trains inertia by controlling the power to the motor, speed builds slowly and is then maintained, a brake circuit causes speed to drop when applied. They don't actually generate any inertia in the loco in the way that a flywheel does, so wouldn't help with loss of contact.
John W.

[dkvfx]

Dunc the 70s books describing controllers with inertia are a bit of a red herring, I've got them and read and understood them. They simulate the effect of a trains inertia by controlling the power to the motor, speed builds slowly and is then maintained, a brake circuit causes speed to drop when applied. They don't actually generate any inertia in the loco in the way that a flywheel does, so wouldn't help with loss of contact.
John W.

I kinda guessed that.

On a side note on this, I had a fiddle with my M&S Flying Scotsman. 4-6-2 with an 8 wheel tender. The middle 6 have pick-ups, as does the 8 on the tender, fed by a delicate connection to the loco. The tender pickups weren't picking up properly, so I sorted them out, and the loco runs pretty smooth. Even so, when one of the pick-up wheels hit a dead spot there is a drop in power. I attached a 12v bulb to the track which also dims at the point the loco seems to momentarily lose power. Is this some kind of back EMF thing? Something I'm aware of, but not something I totally understand.