Re: Hot Snubber

Vollrath, Don <dvollrath@...>

SBT. One joule = 9.478x10^-4 Btu.

DonV

On Mar 15, 2014, at 9:45 PM, "Vollrath, Don" <dvollrath@magnetek.com> wrote:

Max is right folks. One jule is only 0.947x10^-4 Btu. So it would tabs 1056 Jules to equal one Btu. Sorry about that.

DonV
Sent from my iPhone

On Mar 15, 2014, at 12:18 PM, " Max Maginness" <m.maginness@frontier.com<mailto:m.maginness@frontier.com>> wrote:

Err… I think you have your Joules and BTU’s tangled here……

Max

From: WiringForDCC@yahoogroups.com<mailto:WiringForDCC@yahoogroups.com> [mailto:WiringForDCC@yahoogroups.com] On Behalf Of dvollrath@magnetek.com<mailto:dvollrath@magnetek.com>
Sent: Saturday, March 15, 2014 9:09 AM
To: WiringForDCC@yahoogroups.com<mailto:WiringForDCC@yahoogroups.com>
Subject: Re: [WiringForDCC] Re: Hot Snubber

The definition of 'hot' is subjective. If you pinch a resistor between your fingers for 4 or 5 seconds and it is dissipating even 1/4 watt it will feel 'hot'. 1/4 watt for 4 seconds (1 watt-second = 1 Joule) and is enough heat energy to raise the temperature of one pound of water one degree F. Compare the mass of your fingers with a pound of water and you can guess how long it will take to raise the temperature of your finger to a sensitive or even uncomfortable level. If the capacitor is shorted, the resistor will see full track voltage across it. 14V x 14V / 100 ohms = nearly 2 watts.

If you have substituted a different R & C network in that same location and it does not get 'hot', the original capacitor is either the wrong value or faulty. Please throw it out and let's get off this subject.

DonV
________________________________

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------------------------------------

Re: Hot Snubber

Vollrath, Don <dvollrath@...>

Max is right folks. One jule is only 0.947x10^-4 Btu. So it would tabs 1056 Jules to equal one Btu. Sorry about that.

DonV

On Mar 15, 2014, at 12:18 PM, " Max Maginness" <m.maginness@frontier.com<mailto:m.maginness@frontier.com>> wrote:

Err… I think you have your Joules and BTU’s tangled here……

Max

From: WiringForDCC@yahoogroups.com<mailto:WiringForDCC@yahoogroups.com> [mailto:WiringForDCC@yahoogroups.com] On Behalf Of dvollrath@magnetek.com<mailto:dvollrath@magnetek.com>
Sent: Saturday, March 15, 2014 9:09 AM
To: WiringForDCC@yahoogroups.com<mailto:WiringForDCC@yahoogroups.com>
Subject: Re: [WiringForDCC] Re: Hot Snubber

The definition of 'hot' is subjective. If you pinch a resistor between your fingers for 4 or 5 seconds and it is dissipating even 1/4 watt it will feel 'hot'. 1/4 watt for 4 seconds (1 watt-second = 1 Joule) and is enough heat energy to raise the temperature of one pound of water one degree F. Compare the mass of your fingers with a pound of water and you can guess how long it will take to raise the temperature of your finger to a sensitive or even uncomfortable level. If the capacitor is shorted, the resistor will see full track voltage across it. 14V x 14V / 100 ohms = nearly 2 watts.

If you have substituted a different R & C network in that same location and it does not get 'hot', the original capacitor is either the wrong value or faulty. Please throw it out and let's get off this subject.

DonV
________________________________

No virus found in this message.
Checked by AVG - www.avg.com<http://www.avg.com>
Version: 10.0.1432 / Virus Database: 3722/6696 - Release Date: 03/14/14

Re: Loops and Extended Buses

Ed S <eschwerkolt@...>

Doc,

You are not limited to 30 feet or less.  But beyound 30 feet you should twist the bus wires and add a R/C filter (snubber) to the end of the long bus.

Why....  induction in the longer wire will cause spikes and may fry a decoder.

This has nothing to do with amps.

Ed S

At 03:13 PM 3/15/2014, you wrote:

I have read you can go 30' in any direction, even say a star 5 arms each 30' or less.
So what then is limiting the bus to only 30' in a single direction regardless of whether its power is rated 8 or 5 or 3 amps?

Re: Loops and Extended Buses

jazzmanlj

"
What is interesting is that a 180 foot, untwisted bus and looped back on itself functioned without shutting down the command station/booster. Or am I preprogrammed because I use Digitrax exclusively, along with the odd PSX from DCC Specialties.
Somewhere along the line someone mentioned that NCE systems can be used that way, ie with a looped bus.
If one used the 30 foot rule in either direction (60 feet), then in a 180 foot continuous loop track , two boosters and a command station should be used correct?
I have read you can go 30' in any direction, even say a star 5 arms each 30' or less.
So what then is limiting the bus to only 30' in a single direction regardless of whether its power is rated 8 or 5 or 3 amps?"
Doc,
Every layout, like any electronic device is is unique as to how it isdesigned and  laid out.
Recommendations are guidelines to avoid pitfalls. Nothing is written in stone. The complexities can be overwhelming, even for the technical person, myself included!
If we stick to the basics then all can get a better understanding to correct or avoid potential problems.

Just my opinion.

Re: Digest Number 2081 Hot Snubber

jazzmanlj

Hello,
Posted by: "Ed S" Date: Fri Mar 14, 2014 8:23 pm
>His instructions recommend not to using a continuous loop but he
does not give a reason.

StandardS-9.1.2 - 5 end ofsection.
“5. Topology
Only one Command Station signal generator output or Power Station Interface Repeater output
155 may be connected to a Power Station Interface. Inputs of many Power Stations may be connected
in parallel connection to the two wires of the bus. It is acceptable to use tree, star, and daisy chain
connections. However, it is not allowed to connect any part of this bus in a loop. The bus, or
branches, must not create a loop to themselves or to another branch. If multiple Power Station
Interfaces are used on a layout, they must not be interconnected. They should be clearly identified
160 to eliminate possible cross connecting.”
This implies that it is the same track. They should not form a loop.

Good day digital.
Charles_2_Bordeaux.
France.

IMHO the NMRA spec and in many others such as MIL, etc are written not for the layperson but for the technically inclined! Industry specs are meant for highly technical people.That's OK. Technical people, it's our job and we have to scrutinize and understand every sentence!

NMRA sets the standard for manufacturers etc, where technical details are important but these are beyond the average modelers comprehension. Perhaps NMRA or another party should try to adress the layperson and write in terms that could be digested!

Just my opinion.

Loops and Extended Buses

Doc Colin <colinseggie@...>

﻿
Hi All  I agree Len.
What is interesting is that a 180 foot, untwisted bus and looped back on itself functioned without shutting down the command station/booster. Or am I preprogrammed because I use Digitrax exclusively, along with the odd PSX from DCC Specialties.
Somewhere along the line someone mentioned that NCE systems can be used that way, ie with a looped bus.
If one used the 30 foot rule in either direction  (60 feet), then in a 180 foot continuous loop track , two boosters and a  command station should be used correct?
I have read you can go 30' in any direction, even say a star 5 arms each 30' or less.
So what then is limiting the bus to only 30' in a single direction regardless of whether its power is rated 8 or 5 or 3 amps?

----- Original Message -----
Sent: Saturday, March 15, 2014 7:46 PM
Subject: [WiringForDCC] Re: Digest Number 2081 Hot Snubber

Maybe it's time to put the hot snubber to bed and open a discussion as to loops and wiring! That might be more informative and productive.

Re: Digest Number 2081 Hot Snubber

William Teeters <cozyflyr9398@...>

Thank you for explaining that. Bill Teeters

From: CS_listes <charles.soubiran@...>
To: WiringForDCC@...
Sent: Saturday, March 15, 2014 12:04 PM
Subject: [WiringForDCC] Re: Digest Number 2081 Hot Snubber

Hello,
Posted by: "Ed S" Date: Fri Mar 14, 2014 8:23 pm
>His instructions recommend not to using a continuous loop but he
does not give a reason.

Standard S-9.1.2 - 5 end of section.
“5. Topology
Only one Command Station signal generator output or Power Station Interface Repeater output
155 may be connected to a Power Station Interface. Inputs of many Power Stations may be connected
in parallel connection to the two wires of the bus. It is acceptable to use tree, star, and daisy chain
connections. However, it is not allowed to connect any part of this bus in a loop. The bus, or
branches, must not create a loop to themselves or to another branch. If multiple Power Station
Interfaces are used on a layout, they must not be interconnected. They should be clearly identified
160 to eliminate possible cross connecting.”

This implies that it is the same track. They should not form a loop.

Good day digital.
Charles_2_Bordeaux.
France.

Bonjour,
La réponse est ici :
Cela sous-entend qu’il en est de même pour les rails. Ils ne doivent pas former une boucle.
Bonne journée en numérique.
Charles_2_Bordeaux.
France.

Re: Hot Snubber

Theo van Riet

Op 15 mrt. 2014, om 17:41 heeft redking56@... het volgende geschreven:

Steve, the hot snubber had a 1/2 watt resistor, and I initially replaced the 1/2 watt resistor with a 1 watt resistor, but the problem persisted.  When I replaced the capacitor and retained the 1 watt resistor, the snubber became a lot less hot to the touch.

_

Very logic, most of the time it's the condenser slowly deteriorating......

Common illness with condensers..

Even Apple once had a huge problem wth it.

Theo

--
groeten vanop de Heide        -----

Re: Digest Number 2081 Hot Snubber

jazzmanlj

Maybe it's time to put the hot snubber to bed and open a discussion as to loops and wiring! That might be more informative and productive.

Re: Hot Snubber

Max Maginness

Err…  I think you have your Joules and BTU’s  tangled here……

Max

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of dvollrath@...
Sent: Saturday, March 15, 2014 9:09 AM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] Re: Hot Snubber

The definition of 'hot' is subjective. If you pinch a resistor between your fingers for 4 or 5 seconds and it is dissipating even 1/4 watt it will feel 'hot'. 1/4 watt for 4 seconds (1 watt-second = 1 Joule) and is enough heat energy to raise the temperature of one pound of water one degree F. Compare the mass of your fingers with a pound of water and you can guess how long it will take to raise the temperature of your finger to a sensitive or even uncomfortable level. If the capacitor is shorted, the resistor will see full track voltage across it. 14V x 14V / 100 ohms = nearly 2 watts.

If you have substituted a different R & C network in that same location and it does not get 'hot', the original capacitor is either the wrong value or faulty. Please throw it out and let's get off this subject.

DonV

No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1432 / Virus Database: 3722/6696 - Release Date: 03/14/14

Re: Digest Number 2081 Hot Snubber

CS_listes

Hello,
Posted by: "Ed S" Date: Fri Mar 14, 2014 8:23 pm
>His instructions recommend not to using a continuous loop but he
does not give a reason.

Standard S-9.1.2 - 5 end of section.
http://www.nmra.org/standards/sandrp/pdf/S-9.1.2_2012_07.pdf
“5. Topology
Only one Command Station signal generator output or Power Station Interface Repeater output
155 may be connected to a Power Station Interface. Inputs of many Power Stations may be connected
in parallel connection to the two wires of the bus. It is acceptable to use tree, star, and daisy chain
connections. However, it is not allowed to connect any part of this bus in a loop. The bus, or
branches, must not create a loop to themselves or to another branch. If multiple Power Station
Interfaces are used on a layout, they must not be interconnected. They should be clearly identified
160 to eliminate possible cross connecting.”

This implies that it is the same track. They should not form a loop.

Good day digital.
Charles_2_Bordeaux.
France.

Bonjour,
La réponse est ici :
Cela sous-entend qu’il en est de même pour les rails. Ils ne doivent pas former une boucle.
Bonne journée en numérique.
Charles_2_Bordeaux.
France.

Re: Hot Snubber

William Teeters <cozyflyr9398@...>

Rich, Is your buss wire still in a loop? If so, Cut it at a distal distance, and see the results. Bill

From: "redking56@..." <redking56@...>
To: WiringForDCC@...
Sent: Saturday, March 15, 2014 11:41 AM
Subject: RE: [WiringForDCC] Re: Hot Snubber

Steve, the hot snubber had a 1/2 watt resistor, and I initially replaced the 1/2 watt resistor with a 1 watt resistor, but the problem persisted.  When I replaced the capacitor and retained the 1 watt resistor, the snubber became a lot less hot to the touch.

Rich

Re: Hot Snubber

redking56@...

Steve, the hot snubber had a 1/2 watt resistor, and I initially replaced the 1/2 watt resistor with a 1 watt resistor, but the problem persisted.  When I replaced the capacitor and retained the 1 watt resistor, the snubber became a lot less hot to the touch.

Rich

Re: Hot Snubber

Ed S <eschwerkolt@...>

Rich,

Yes that seems to be the solution.

Now run some trains and have fun.

Ed S

At 12:29 PM 3/15/2014, you wrote:

Yes, that is correct.

So, I take it that leaving the bus wires disconnected at that point would be the way to resolve the matter.

No more "continous loop" as I call it, relative to the bus wires.

Rich

Re: Garden layouts/Booster Protective Housing

jazzmanlj

We can put this subject to bed!

Best to have multiple boosters in one location out of the elements. A central control/wiring is best.  I'm not concerned about quality of wire in the elements. It takes years for problems to arise and things always change.

Thanks all,

Re: Hot Snubber

Steve Haas

<<Just now, I went down and inserted the hot snubber on my bus wires over by snubber #6 where that snubber is warm at best.  Very quickly, the resistor on that hot snubber got extremely hot, for whatever that is worth.>>

Rich,

Is there any chance the resister in the “hot” snubber is of too small a wattage?  That alone could cause the resistor to run hot (see another recent conversation on this topic).  I’m willing to bet the “hot” snubber has a lower wattage resistor compared to the others. Replace the resistor with at least a ½ watt resistor and see what happens.

Best regards,

Steve Haas

Snoqualmie, WA

Re: Hot Snubber

redking56@...

Thanks, Steve.

Rich

Re: Hot Snubber

redking56@...

Yes, that is correct.

So, I take it that leaving the bus wires disconnected at that point would be the way to resolve the matter.

No more "continous loop" as I call it, relative to the bus wires.

Rich

Re: Hot Snubber

Steve Haas

<<This question may have gotten lost in all of these exchanges.>>

<<Does it matter how many feeders are between two snubbers?>>

No – the number of feeders between snubbers makes no difference.

<<Does it matter what type of device is connected to a feeder besides rail, such as an NCE Switch-It or Mini-Panel or Circuitron Flasher, or Digitrax AR-1?>>

NO – device types do not matter.

Best regards,

Steve Haas

Snoqualmie, WA

Re: Hot Snubber

Ed S <eschwerkolt@...>

If I understand, when you disconnected the loop between the R/F Filters , the resistors stayed cool...

Bingo...

Ed S

At 11:53 AM 3/15/2014, you wrote:

disconnected the bus wires just to the right of the #3 snubber, Waited several seconds, then touched the resistor on the #4 snubber. It was cool to the touch.

Rich

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