Hi All,
Here's what I want to do:
Program Micro-Tsunami's and QSI's with a Zephyr and Decoder Pro.
Which interface do you recommend? I was looking at the Digitrax PR3.
If I purchase that do I need a booster as well (PTB-100 or Powerpax)?
Thanks for the help
Birdog
Have you considered using Ops Mode (on the main) programming? Zephyr also has an undocumented "blast mode" which applies full mainline power to the programming track.
Jim,
I did see that information somewhere. Yes I have considered that, however I really like the idea of being able to program with decoder pro. Seems like the easiest way to go and my finger won't get bloody punching buttons.
Do you have a thought on having to use a booster along with the PR3, Zephyr and decoder pro? I am unsure if I need to have one. I read in the PR3 info off the Digitrax website that a booster is not needed. Is that correct?
Birdog
According to Digitrax, a booster is not required as the PR3
also acts as a booster.
Tim Anders
Souderton, PA
Tim,
Yeah that's what I gather from their website as well. But I have been told from a DCC dealer(a reliable one too) that I definitely need a booster. So I am getting conflicting info. ???
I guess I can get the booster anyway but if I can save the $$ I'd like to.
Does anyone else have a tip?
Thanks, Birdog
Purchase a booster only when you determine you need one.
Birdog
As Hunt says wait until you have it hooked up and running.
Don't spend money you don't have to.
Tim Anders
Souderton, PA
There seems to be some confusion over what constitutes a booster. Your Zephyr is a throttle, command station and booster integrated into one package. But when you use the programming output, the booster is normally bypassed. Thus the suggestion to use OPs mode programing on the main where the full 2.5 amp output is available for programming. OPs mode works just fine with Decoder Pro - I use it all the time for non-sound decoders. Others use it with sound decoders.
Blast mode reconfigures the Zephyr internally to deliver full booster power to the programming track. I do not use blast mode on my Zephyr because I do not need it for my decoders. But my understanding from the folks on the JMRI and Digitrax Yahoo groups is that it works just fine with Decoder Pro. The limitation with blast mode programming, as with OPs mode programming, is that you cannot read back from decoders. This is not a great problem with Decoder Pro as you normally have a saved record of how you programmed the CVs for each locomotive and if they go bad, you just reload them with a couple of key strokes.
The PR-3, as I understand it, will interface with your computer via USB, can drive a programming track at a level high enough to program most decoders, and can interface via LocoNet with a model railroad that already has a booster for running trains. With the computer connected, it can program in Decoder Pro. Someone else will have to tell you whether the PR-3 is bi-directional, that is, whether it allows you to read back from decoders. The PR-3 also allows you to massage and download sound files into Digitrax SoundFX decoders.
If you want to use your computer to run your railway via a PR-3, yes, you will need a booster. Fortunately, you already have one - in your Zephyr. Panel Pro, which comes along with Decoder Pro, is one approach to doing just that.
Edit - replace "boost mode" by "blast mode." Thank Hunt, glad you were more awake than I was!
Jim
The powerpax and others are sold as programming boosters.
This is the booster we are referring to.
Tim Anders
Souderton, PA
Tim, I will try to simplify what I am saying:
If the output level of a PR-3 isn't high enough, you can use the booster in your Zephyr to increase power to your programming track.
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Birddog also asked for recommendations on the type of interface he needs.
A PR-3 is a good choice of interface to use with Decoder Pro. You can use it directly for programming, use it boosted by your Zephyr, or link Decoder Pro to your Zephyr with it. As a bonus, you can also modify sound files in certain decoders.
LocoBuffer-USB might be a better choice if you are worried about damaging an expensive computer. It will NOT program decoders directly and it will NOT upload sound files to any decoders, but it works very well linking Decoder Pro to your Zephyr and it fully protects your computer against spikes, ground loops, ringing, and other errant currents.
Overall, I would recommend the PR-3 and a junker computer to connect it to. If you don't have one in the back of a closet, they are often free for the asking. On the road I run Decoder Pro under Windows 98SE on an old laptop that won't support anything higher. It works just fine with my LocoBuffer-USB and Zephyr and runs almost as fast as it does at home on a 3 GHz machine running XP. For the PR-3 you would need a computer capable of supporting XP.
Jim,
Fantastic info! You have explained it very clearly. My hunch was just what you said. I don't plan on running my railroad with it I just want to build a roster of locomotives with Decoder Pro and program the decoders(but I do have that option in the future). It sounds like the PR3 will do that for me. And if I need more power I can use the Zephyr. I know it's tough for the maufactures to keep up with the fast pace of what we want and what we are trying to do and it's extremely nice to be able to query the knowledgebase you and the others provide. I really appreciate the help and tips from everyone and hopefully I can "pay it forward".
Cheers!
Birdog
If I were to get a Digitrax Zephyr for programming decoders I've installed myself, would I be able to connect my Bachmann 5 amp booster to it, or is it made to accept only a Digitrax booster?
Could I connect the power pack from my DC train set to the Zephyr as a throttle? I read the Zephyr manual, & it doesn't even discuss controlling multiple trains with the Zephyr's throttle. I can probably run 5 trains simultaneously with EZ Command better than 2 with Zephyr from one throttle.
With a Digitrax decoder I installed into my Blueline Mikado, I found that there is no momentum; the loco accelerates & decelerates quickly. Also, the master volume seems to be at maximum, which is too loud. I would like to be able to program this features, but it might be cheaper to take my two Blueline locos to a hobby shop for programming.
You can run multiple engines simultaneously with the Zephyr. Digitrax expalains how here:
http://digitrax.com/kb/index.php?a=885
The Digitrax site is a great place to look for Q and A about their products. they also respond to E-mail promptly.
As far as running your Bachmann booster with the Zephyr, don't do it unless you can find specific instructions from DIGITRAX on how to do that.
You can use two NON-PULSE POWER power packs with your Zephyr. Each one can control a single loco. Digitrax calls them Jump Throttles.
I own a Zephyr and am quite taken with it. It is easy to use and has LOTS of features that separate it from EZ Command. If you get one, I think you'll like it, too.
Rusty
For programming just two locomotives on a one time only basis, it would very likely be cheaper to take them to the local hobby shop than to buy a Zephyr to do the job. But what about next time? And how do you tell the programmer at the hobby shop just how much momentum to program into the decoders? Same question about volume. These numbers are usually arrived at by a trial and error process.
The E-Z Command definitely has the best system for running many trains from one throttle. Nothing beats pushing one button to transfer the throttle to a different train, both in terms of speed and in terms of convenience. However, as has been pointed out, the Zephyr allows you to use two jump throttles, which means you do not that to push any buttons when running three trains. While the number of jump throttles is limited to two, the number of regular throttles can be as many as ten. Many times four friends and I ran five trains at a time, one each, and each one run with a separate throttle. The limitation in our case was the 2.5 amp output of the Zephyr. To run more than five trains at a time, I had to buy a booster.
I cannot tell you whether or not an E-Z Command booster can be used with a Zephyr. Boosters can have two types of inputs - low level or high level. A low level input connects to the throttle bus or expansion port and is unique to the manufacturer. A high level input connects to to the rail outputs of the command station and generally will work with any manufacturer's command station. I do not own an E-Z Command booster and do not know what type of input(s) it has. Perhaps someone who does know will pass their knowledge on.
Jim
the EZ commnad booster is a High level input, and amplifies the track power/command signal to 5 amps. the supplied input cable is set up to connect to the EZ command, and will have to be modified for use with other brand systems (one of the plugs has to be cut off).
Thanks Rusty, Jim & Robert, for your help. I am left wondering what Digitrax means by a "smooth power pack," & whether or not the power pack that came with my Walthers LifeLike DC train set qualifies. I will check the Digitrax website.
they mean "not a Brick" those little square packs that come in starter sets, but something like the mid priced mrc tech 2's.
Then buying throttles would become expensive. ::)
They mean a power pack that does NOT use PULSE POWER to improve slow speed performance. My guess is that most, if not all, trainset packs would be okay. They usually are bottom of the line packs. Check your documentation. Most packs that use pulse power have a switch on them that says "Pulse Power," but some MRC units, I believe, work automatically. Hope this helps.
Rusty
A neater solution for jump throttles is to use a potentiometer for a speed control, a battery (or 12 volt battery eliminator), a DPDT toggle switch for direction control, and a SPST toggle switch for on/off. Put these four items in a small case, add a knob and a length of wire, and you have a hand held, tethered throttle. These are ideal for a small to medium layout or a yard control, even on a very large yard. Circuit diagram available on request.
Note that jump throttles, including the one above, have no function buttons. But you can turn headlights on at the Zephyr when you assign a particular locomotive to a jump throttle and they will reverse automatically when you reverse direction. This is really handy when you are switching as the lights are a quick reminder of which direction the locomotive will move.
Jim
for about the same price of a power pack, $60, you can buy a digitrax UT4 throttle that plugs right in, has 12 functions, and with the use of UP5 panels, is a walk-around throttle add-on to your Zephyr system.
Thanks, Rusty. My LifeLike power pack has no pulse power switch. I'd prefer to be able to use it rather than pay $60 for a throttle in addition to buying a Zephyr. Some have bemoaned that Digitrax has not improved Zephyr since it won awards in 2002.
One reviewer said, "It definitely needs an LCD panel with a menu driven interface. Personally I'd like a recall switch that let's you toggle the last two locomotives without having to enter an address." http://modeltrains.about.com/b/2008/07/28/does-digitrax-need-a-new-zephyr.htm
It's true that the Zephyr has its shortcomings...but it has one great asset and that is Digitrax's commitment to LocoNet. I can still use a booster I bought back in the mid-90's to run a second power district and my original throttle still works fine. Although it's limited to 2-digit addresses, it does give me a walk-around capability. For 4-digit addresses, I use my new UT-4 throttle or the throttle on the Zephyr itself. So I have pieces dating from 1995 to literally last month, and they all work just fine together.
Rusty
Rusty, almost all my locomotives have 4 digit addresses. To run one with a Digitrax UT-1 two digit throttle, I just set the locomotive's advanced consisting address to a two digit number. By the next time I run this locomotive, I may have forgotten what address I set it to, or even that I did set an advance consist address. But when I find it will not run on its 4 digit address, I am already half way there to clearing CV19 in OPs mode. This process saves two trips to the programming track and is quick and easy.
Jim
Hey, Jim,
Thanks for the CV-19 tip. I appreciate it.
Rusty
Rusty, apparently, if I wanted to use my Bachmann 5 amp booster with a Digitrax Zephyr, I'd have to create a second power district insulated from the first (which I'd have to learn how to do). So I see another thing I like about EZ Command: connecting it to the booster. It's too bad any booster can't be connected to any DCC control.
When NMRA created the DCC standard, it was decided that the dividing line between manufacturers and users was going to be the tracks. Everything on the system side of the tracks--the booster, command station and throttle, etc., could be proprietary. In other words, the system components can all communicate as they see best. Everything on the user side of the tracks--basically, the decoders--has to adhere to the DCC communications standard.
The result of this scheme is the very high degree of interoperability between systems and decoders, while allowing manufacturers to optimize their networks. For alll boosters to work with all command stations and throttles, NMRA would have had to write a standard that described every single component, and might well have proven to be unworkable. He who governs least governs best.
Rusty
Quote from: Birdog on January 23, 2009, 05:00:25 PM
Hi All,
Here's what I want to do:
Program Micro-Tsunami's and QSI's with a Zephyr and Decoder Pro.
Which interface do you recommend? I was looking at the Digitrax PR3.
If I purchase that do I need a booster as well (PTB-100 or Powerpax)?
Thanks for the help
Birdog
I'm going to start some controversy concerning some sound decoders and boosters.
I've been using my Bachmann EZ Command for over 4 years. I also added the Bachmann 5 amp booster, glad I did. Cost is more than some, but in my opinion Bachmann is high end in their booster, meaning, the circuit breaker and the cooling fan.
But proper buss and feeder wiring is utmost important when using boosters with DCC.
I have a friend on one of the other forums who also uses Bachmann EZ Command. Instead of purchasing the Bachmann booster he saved some money and bought one for like $69.00, not sure of the manufacturer, but if I find out, I'll post it. Worked good for a year or 2. But something happened along the way. On derailments, he was frying decoders, expensive ones I might add. It seems he ignored the quarter test, until he finally decided it might be the booster, like other posters were telling him, after all how could it be that, it's fairly new, he thought. Well it failed the quarter test in that the booster would not break the current during shorts. He needlessly spent a lot of money on decoders, burning them up. All he had to do was turn on the booster, put a quarter across the track and see what happens, the booster should have kicked off until the short was corrected. You get what you pay for...Thank you Bachmann for a great product in your booster.
Another guy had problems with his booster failing the quarter test also. He apparently used too light of buss wire and drop feeders, something like #18 buss with #24 drop feeders. The booster failed because in simple terms, the correct current wasn't being delivered to the rails due to the wire size. I would imagine a 4X8 layout would have no effect but if your running 300 ft of wire, different story.
My experience with the Digitrax PR3 programmer. You still need a power supply with it, it tells you that even in the advertisements. I purchased the Digitrax PS14 Power Supply when I bought it. Now all worked well until I installed a Tsunami sound decoder, just not enough power from the PS 14. I had a spare power pack from an extra EZ Command and plugged it in the PR 3 and I was then able to program the Tsunami. I did the same for the BLI Blueline Loco's. There is a problem trying to program those, being you have to program 2 decoders in one loco. I found that by using the EZ Command power pack it worked fine. Now that may be too that the first BLI I did, I used a Digitrax motor decoder DZ143PS and had problems programming. Had to turn the motor decoder off and program the sound. Turn the sound off an then program the motor. However on my second attempt I purchased a TCS motor decoder for another BLI Blueline and low and behold, I could program both the same time, I didn't have to turn nothing off. I don't know why that could be but it worked.
Now The Quantum Revolution sound decoders (QSI) I'm sure you have to purchase their programmer, correct me if I'm wrong, unless they are already loaded in the loco you purchase such as BLI, Atlas. I know that I am very happy with my PR3 and the JMRI program. You don't have to know all the CV's, some are very important and it's a learning curve .Just slide the bars for the sound or move the speed steps on the table in the program, try it on the layout, if you're not satisfied just keep tweaking until you are satisfied. Just a nice simple way to program, and I highly recommend it.
It's also great for those consists you would like to build, but those loco's that run way too fast or too slow, are now under my control and I can build any consist I choose to, simple and easy!
Hey if you mess up, simple, you won't and can't hurt anything, just reset the decoder back to factory reset and start over, it's all in the learning.
Quote from: WGL on May 19, 2009, 02:30:06 AM
... if I wanted to use my Bachmann 5 amp booster with a Digitrax Zephyr, I'd have to create a second power district insulated from the first ...
That would be true only if you wanted to use the output of your booster and the output of the Zephyr at the same time. Then you would have a total of 7.5 amps available to your layout, 5 amps in one power district and 2.5 amps in the other. **
But if you want to connect your booster and a Zephyr the same way as you do with the E-Z Command (output of the command station to the input of the booster, output of the booster to all the trackage) then you would have the same 5 amps available as you would with your E-Z Command setup.
** Note: For technical reasons, you may not be able to use both outputs at the same time, even if you set up two power districts. Some boosters are designed in such a way that you cannot use more than one of them on a layout. The MRC Power Station 8 is such a booster. The jury is still out on the E-Z Command booster.
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Quote from: Rangerover on May 19, 2009, 10:03:40 AM
... He apparently used too light of buss wire and drop feeders, something like #18 buss with #24 drop feeders. The booster failed because in simple terms, the correct current wasn't being delivered to the rails due to the wire size. I would imagine a 4X8 layout would have no effect but if your running 300 ft of wire, different story ...
I suspect it was his under sized bus wires that got him in trouble. I use #24 feeds on all my trackage as long as they are less than 3 feet long and have no problems with quarter tests, even though I use an 8 amp booster. What size booster was your friend using?
Quote from: Rangerover on May 19, 2009, 10:03:40 AM
... I had a spare power pack from an extra EZ Command and plugged it in the PR 3 and I was then able to program the Tsunami. I did the same for the BLI Blueline Loco's. There is a problem trying to program those, being you have to program 2 decoders in one loco. I found that by using the EZ Command power pack it worked fine. Now that may be too that the first BLI I did, I used a Digitrax motor decoder DZ143PS and had problems programming ...
I am glad this worked for you without damaging your PR-3 or any decoders. Did you happen to measure the actual output of the E-Z Command power pack with just the light load of the PR-3 connected? I am betting it was a lot more than the 15 volts the PR-3 is rated for. A measurement of the track voltage would be interesting too. It could easily be more than the 18 volts maximum that the early DZ125's were rated for.
Bottom line, boosting the voltage for programming is not the same as boosting the available current. It may program some of the decoders all of the time and all of the decoders some of the time. The rest of the time, don't inhale the smoke.
Jim
I am glad this worked for you without damaging your PR-3 or any decoders. Did you happen to measure the actual output of the E-Z Command power pack with just the light load of the PR-3 connected? I am betting it was a lot more than the 15 volts the PR-3 is rated for. A measurement of the track voltage would be interesting too. It could easily be more than the 18 volts maximum that the early DZ125's were rated for.
Bottom line, boosting the voltage for programming is not the same as boosting the available current. It may program some of the decoders all of the time and all of the decoders some of the time. The rest of the time, don't inhale the smoke.
Jim
NO NO NO NO...I'm a little smarter than that. I checked the voltage with a meter for the EZ Command power pack before I plugged her in. Output is 14 volts ( though it says 16 volts output on the power pack) and the PR is 12-15 volts. I am however ordering the Power Pax programmer from Tony's. I use a quality electricians volt ohm meter, not a cheap $25 meter. I don't particularly like taking chances.
It's cheaper $50.00 for the Power Pax than smoking a $100.00 decoder, what worked for a shortcut once, may not work again, so I won't take that chance either. And that programmer will program the Tsumani and QSI and other power eating decoders. Mama didn't raise no fools!
As far as the digitrax decoder it wasn't an early DZ125. It was a DZ 143PS in fact and it was on the list of recommended decoders from BLI for that particular loco which I already had on hand. The digitrax PS decoders are for Z scale loco's but work in HO scale also. There is a "room for question" so I used what BLI recommended.
note...I have a separate program track I use to program off the layout. I don't have the computer in the train room. But I am considering buying a cheap laptop for the train room and then can program on the main and run the layout using the JMRI Panel Pro. But I also have a separate program track that is completely isolated from the layout in my yard area. That's where I program Bachmann diesels to the command station. You can't program anything with them with any system that I know of, not even speed steps, if you know of how to program them, please enlighten me.
Rangerover, you win the bet and I will gladly buy you a beverage of your choice next time you are in Saskatoon. I had in mind that the E-Z Command power pack was up around 18 volts unloaded but I just checked three of them and measured 16.0, 16.0 and 16.1. The odd ball was an older one, identical with the other two except for having a primary power cord instead of the prongs built in. The difference in our measurements of output may be just the difference between US line voltage and Canadian line voltage (ours is 120 volts and was bang on during this test) and are not significant. I used a $14 DMM that I check from time to time against my AVO meter (model 8 mark III with traceable calibration.) I like the low cost meters because I can throw them in the tool box and even if I run over one with my truck, I am not out much. I rarely use the AVO directly because there is no way I could ever afford to replace it.
I did read and understand that you were programming a DZ143. The comment about the DZ125 if for the next guy who may not realize the difference. In fact, Digitrax now rates the DZ125 at 22 volts but there may be some of the earlier ones still around. But again, using a 15 or 16 volt supply on your PR-3 should not affect even one of the older ones. I would be interested if you could tell me the track voltage with the PR-3, either with its own power supply or with the E-Z Command one. You have got my curiosity going here.
Jim
Quote from: Jim Banner on May 19, 2009, 05:38:33 PM
Rangerover, you win the bet and I will gladly buy you a beverage of your choice next time you are in Saskatoon. I had in mind that the E-Z Command power pack was up around 18 volts unloaded but I just checked three of them and measured 16.0, 16.0 and 16.1. The odd ball was an older one, identical with the other two except for having a primary power cord instead of the prongs built in. The difference in our measurements of output may be just the difference between US line voltage and Canadian line voltage (ours is 120 volts and was bang on during this test) and are not significant. I used a $14 DMM that I check from time to time against my AVO meter (model 8 mark III with traceable calibration.) I like the low cost meters because I can throw them in the tool box and even if I run over one with my truck, I am not out much. I rarely use the AVO directly because there is no way I could ever afford to replace it.
I did read and understand that you were programming a DZ143. The comment about the DZ125 if for the next guy who may not realize the difference. In fact, Digitrax now rates the DZ125 at 22 volts but there may be some of the earlier ones still around. But again, using a 15 or 16 volt supply on your PR-3 should not affect even one of the older ones. I would be interested if you could tell me the track voltage with the PR-3, either with its own power supply or with the E-Z Command one. You have got my curiosity going here.
Jim
Hey Jim I ain't bet'n, heck I'm only learning and I'm way behind you guys with DCC. I got curious from your post. I thought he must know something that I don't nor was I concerned before. What I found out is weird to say the least.
The extra Bachmann EZ Command power pack is measuring 14. 35 volts out of the wall. That's the one I used on my program track. Hooked up to the PR3 I get 14 volts on the track with a loco turned on. Well I kind of knew that from when I first measured it.
The Digitrax PS 14 reads 14.96 volts out of the wall, but only 8.31 volts on the track with a loco turned on and 12.35 volts with nothing on the track. Strange!!!!!!!
The Bachmann EZ Command I run on the layout with the 5 amp booster measures 16.97 out of the wall and 15 volts avg on the layout track measured in various places, with no loco's on the track, I knew that though. I have quite a number of led's that are on with the track power on so I accept the loss of voltage there.
The 2 Bachmann EZ Command power packs are identical in appearance and the extra one I had was never used in the 3 years or so since I bought it until I used it with the PR3. Odd !!!!!!!!!! One measures 14.96 while the other measures 16.97.
I sure am glad I mentioned this, thanks for your warnings I appreciate it. Fortunately I plugged the right one in the PR3, no more. I'll wait for the Power Pax to program the Tsunami and other such sound decoders as per Tony's Trains suggestion.
Rangerover, you may be onto something. It sounds like your PS14 is not putting out enough current to properly program the decoders you had trouble with. I wonder if this is because the PS14 is a tranformerless supply with current limiting. (You can tell transformerless supplies by their light weight compared to transformer ones of similar current rating.) The older PS12 which they used to reccommend for the PR-3 had a transformer and would happily go into overload, at least for short periods of time. So it could produce more than 300 milliamps if asked to and do it without a great deal of voltage loss. But current limiting supplies drop off very quickly above their rated current. Needless to say, your E-Z Command supply, which is rated at 1000 milliamps and you know produces 14 volts is not being loaded down so badly. You might want to confirm this with an email to Digitrax, but in my opinion, you should be okay with that particular E-Z Command power supply.
The link below is the manual for the PR-3. On page 4, they mention a blinking red LED if the output falls too low. Did you by any chance notice this with the troublesome decoders when using the PS12?
http://www.digitrax.com/ftp/PR3%20Programmerweb.pdf (http://www.digitrax.com/ftp/PR3%20Programmerweb.pdf)
Jim
p.s. we are all learning, and learning from one another.
The link below is the manual for the PR-3. On page 4, they mention a blinking red LED if the output falls too low. Did you by any chance notice this with the troublesome decoders when using the PS12?
http://www.digitrax.com/ftp/PR3%20Programmerweb.pdf
No nothing with the leds were anything out of ordinary. I studied those leds for hours, I must say when first reading the info on the leds was confusing, I did experiment by disconnecting the power supply to see for myself what they meant. Also the same with disconnecting the track power wires and the USB port, just so I would know why an led was blinking different than what normal is.
I really don't feel comfortable with continuing use of the Bachmann power pack programming with the PR3. I bought the PR3 for a specific reason, so I could download loco sounds from the soundloader program using the digitrax soundbug. Also it gave me the interface so I could "play" with cv's using the JRMI program since I'm using the Bachmann EZ Command which we all know has no cv programming capability. I won't knock Bachmann for that, but for the low cost and simplicity of Bachmann I don't think I would be this far in my adventure of DCC. I love it by the way!
One of our friends and posters here (Stephen) stopped by a few weeks ago at my home and I of course showed him my pike. He was praising the Dyamis System, which I am taking an interest in.
The Power Pax system has more of what I need in so far as protection with still the right juice, so to speak, to program the more sophisticated sound decoders. I would imagine the frustration of smoking a $100.00 decoder in seconds if something was shorted out in my installation that the Power Pax would detect and cut off so as to prevent the loss. That Bachmann power supply won't do that. Here's the last paragraph from Tony's which really sums it up for my reason to purchase that power supply.
How PowerPax Works:
PowerPax is microprocessor controlled. When hooked up for programming, the PowerPax initially provides power to the programming track to charge-up decoder components like capacitors that would otherwise reduce programming energy and cause a programming failure. When you initiate the programming sequence through your DCC System, the PowerPax also boosts and controls the programming energy to about 200 mA. In the event of an overload or short the PowerPax instantly shuts down to protect the decoder and your DCC System's programming circuits.
http://www.tonystrains.com/technews/powerpax.htm
Hey Jim I read your posts and all I can say is I'm glad your here and pointing guys like me in the right direction, thanks, my name is Jim also!