Now This Is Weird - A Major MRR Supplier Dissin' Another on Their Website

[Paradise275]

We must all keep sight of the fact that Rapido does not produce the decoders.
The same decoder manufacturer produces decoders for the open market and
we install these decoders in our locos. As well, other locomotive manufacturers
that have DCC and sound on board could be using the same decoder manufacturer.
I, for one would be reluctant to run a DCC/sound locomotive using a power pack that
doesn't have a regulated power output. Digitrax has setting for N and HO to limit the
amount of power supplied to the rail. I don't think a DC power pack has the same ability.

Rick

[CBQ Fan]

Often it is not what you say, it is how you say it. 

[AKNscale]

The last time I ran a DCC loco on DC it caught a switch and stalled. I turned the power up slightly and was about to tap it forward when it burned up. That was when I decided DCC was the way to go for me, besides that the improved functionality is well worth it.

[reinhardtjh]

Weren't some MRC packs deliberately designed for "pulse power" ?

I was always warned to stay away from them.

Seriously, who has an oscilloscope to check this out???

This.  There was a time when one certain line of MRC power packs had a pulse power feature that totally confused almost every DCC decoder on the market.  I'm sure a search would find threads on TRW discussing this.  I don't remember which line of power packs it was, but it could have been the 1300 series.

[Doug G.]

How? Because they warn people that MRC's old technology will damage their locomotives? that seems like the right thing to do to me.

The "...notorious for voltage spikes..." is what's poor. It should have been worded like, "We have received reports from the field that our locomotives may not be compatible with some older DC power packs and we advise not to use those with our locomotives."

To single out a design that's been on the market for years and has been used to power many hundreds, if not thousands, of model locos successfully, is irresponsible. It's not as if it was MRC's responsibility, 25 years ago, to make sure their design would be compatible with some future technology. And, as a matter of fact, it more behooves the designers of newer technology to make it backward compatible, if anything. That used to be the "standard" in design and it has been callously discarded during the last 20 years or so.

And the whole "pulse power will ruin model locomotives" thing is ridiculous, too. I have used pulse power my whole model railroading life and have never burnt a loco with it. It's called being careful.

Doug

[wcfn100]

The "...notorious for voltage spikes..." is what's poor.

It also suggests that they knew about the issue but went ahead with the design anyway.

Jason

[peteski]

It also suggests that they knew about the issue but went ahead with the design anyway.

Jason

They?  Aren't Rapido decoders made by ESU anyway?

[peteski]

And the whole "pulse power will ruin model locomotives" thing is ridiculous, too. I have used pulse power my whole model railroading life and have never burnt a loco with it. It's called being careful.

Doug

Pulse DC power is not recommended for coreless motors.  But I doubt that it will burn them out in normal operation.  However this is an issue unrelated to this discussion.

Pulse DC power should not damage a decoder unless the pulses are higher voltage than what the decoder was designed to withstand.
Pulsed DC can affect a decoder in couple of ways:

1. If the filter capacitors in the decoder aren't high enough of a value, the microcontroller (the "computer brain" of a decoder) power will also be pulsed (so it will behave erratically).
2. If the filter caps in the decoder are large enough to smooth out the pulsed power, the decoder's circuit which is responsible for detecting DCC packets could be confused, and the decoder might again behave erratically.

I think  there is some confusion about pulses and spikes. Pulses have amplitude which is within the safe operating range of the model (lets say less than 16V). Voltage spikes are very short pulses which have a voltage much higher than what the model is designed for.  Those can cause damage to decoders (but are usually absorbed and dissipated by the motor in a DC-only model).

[wcfn100]

They?  Aren't Rapido decoders made by ESU anyway?

Could it be something other than the decoder?  The Rapido site doesn't mention it's the decoder and they say they can fix a locomotive "if they have parts".  If it is just a normal ESU decoder and not something Rapido had built to their spec, I would think we'd here about about this issue from other manufacturers and individuals.

Jason

[brokemoto]

I have two of the MRC 1300 power supplies.  I use them on my nineteenth century pike.  It supplies power to Atlas, Atlas/MicroAce, MDC/Athearn and B-mann locomotives.  All of them are DC.  I have yet to have a problem.

I have three MRC 2500 power supplies.  The pulse on them is quite strong.  They have confused B-mann factory decoders; specifically: when the directional switch was thrown one way, they went the opposite.  This is similar to the "train set" quality MP FP-7 and some of the C-C RDCs.  I do not use them much.

The one that I use the most is the MRC 2800.   It has a discreet pulse.  It has fried more than one B-mann decoder.  This has forced me to wire around it.  What is funny is that on DC, the B-mann runs much better without the decoder.  I am referring to the 4-6-0, the 2-6-0, the seventy tonner, the forty four tonner and the doodlebug.  I do have an EM-1 that still has its decoder.  Oddly enough, the slow speed on that one is pretty good on DC.

Recently, I purchased an MRC/MP eight wheeler that has sound and DCC.  It runs best on the TECH-7.  On the 2800, it will do no more than forty-five SMPH, which is fine for my purposes.  It does run slightly better on the Kato power supply than it does on the 2800, but not as well as on the TECH-7.

I do have a few 2400s.  In reality, I like them the best as they do have the ON-OFF pulse switch.

I fried a couple of motors on the old B-mann "FP-9" with an MRC 2800.

I do not use DCC.

I would not call the MRC 1300 series a "train set" power supply.  When I think of a "train set" power supply, I think of the little box things that B-mann and MP used to sell.  In fact, I think of the current B-mann DC power supply as a "train set" power supply (the flat thing with the dial and the plugs and jacks).

[wcfn100]

Turns out I have a Railpower 1300.   

Jason

[peteski]

I have two of the MRC 1300 power supplies.  I use them on my nineteenth century pike.  It supplies power to Atlas, Atlas/MicroAce, MDC/Athearn and B-mann locomotives.  All of them are DC.  I have yet to have a problem.

I would not call the MRC 1300 series a "train set" power supply.  When I think of a "train set" power supply, I think of the little box things that B-mann and MP used to sell.  In fact, I think of the current B-mann DC power supply as a "train set" power supply (the flat thing with the dial and the plugs and jacks).

DC locos can take a (voltage) licking. The motor is basically just a coil of wire which will readily absorb short burst of higher voltage (spikes).  So could headlight bulbs. LEDs are more sensitive but depending on how they are wired, then can take a beating too.  I wouldn't expect you having problems. MRC 1300 throttle has been around for decades and nobody complained about DC models being damaged.

[John]

[ Guests cannot view attachments ] I have an old MRC Tech 1400 power pack as well that I occasionally use to break in locomotives if I don't have a decoder handy for the locomotive .. It's over 20 years old .. but does the job .. I was never happy with running decoder equiped  loco's on DC . so I don't ..  while technically decoders support DC mode, doesn't make it a good idea .. if you are going to spend a lot of money to decoderize, then run them that way ..

[Rossford Yard]

Often it is what you say, it is how you say it.

Or as I (and many) say, "It's all in the presentation."

Back on topic.....

First, I asked, and someone seems to have confirmed that the 1300 actually did get some upgrades over the years, despite using the same model number?

Second, I have to wonder if ESU (and others) actually make slightly different levels of decoders?  Sort of like going to Best Buy and seeing "Best Price in Class" on a TV, but that model is a class of one, since BB suggests the specs they want to keep the price in their sweet spot?  In other words, is it possible that Rapido has slightly different decoder specs, maybe to save a buck or two to keep their loco prices in line?  They seem to do unique models, which we presume would sell less and require overhead to be spread over fewer units, so there may be some cost pressures?  And that somehow, that model of decoder is more sensitive to DC?

Not insinuating or accusing, just asking if anyone has ever heard of anything like that.  IF something like that is possible, I can see questioning the level of backwards compatibility that would be needed between the highest tech new locos and older DC power packs.  It might not even be "cheaper" as much as a design trade off for better DCC performance at the expense of worse DC performance, which I am sure they will tell you they think is quite rare, especially with lesser packs. 

Put another way, how many model railroaders are going to have a Unitrak loop set up on the kitchen table with a DC pack and DCC ultra equipped locos?  I am surprised at the number here, apparently, and wouldn't fault Rapido for assuming that number was close enough to zero to ignore or dismiss that as an issue.  Again, its all in the presentation.

[rapidotrains]

After our 100th burned-out customer decoder caused by 1300-series power packs, we added the warning and stopped covering decoders killed by 1300s under our warranty. There are no issues with any other MRC products - just the 1300s. The 1300s burn out ESU decoders. This isn't an opinion. It's not a critisicm of MRC. It's simply a fact.

Our test track uses a Tech3. I have Tech2s at home. Dan uses a Tech4. We have an MRC Prodigy system on one of our display layouts. We love MRC as a rule. Their other products have no problems.

1300s will burn out your ESU decoder. If you use a 1300, your decoder is not covered under the warranty.

Similarly, if you use a trainset controller or one you built yourself, your decoder is not covered under the warranty. We've had people destroy a $350 locomotive with a 1970s Lionel HO trainset controller. These guys would never consider charging their iPhone with that transformer, yet for some reason they think model trains should be compatible with stuff that was cheap quality 50 years ago.

We try to make our models as backwards-compatible as we can, but it's just not possible to make a state-of-the-art, sound-equipped model from 2018 work reliably with every DC controller ever built from the 1930s to today.

-Jason