Ripple-Free DC Power Option SOLVED!

I have considered adding a Piko 5 amp, 22 volt controller and transformer to see if it has smoother slow speed control with LGB locos.

Well the MRC Power Supply is ok but the DC out isn't very clean. I believe they stopped making them and MRC never really offered any service for them when they fail. I had one years ago and sold it after checking the output on a oscilloscope.

Me I stick with Bridgewerks as USA made and they'll fix any power supply they ever made for $90 and that includes free return shipping.

Far as the Piko units I have no opinion on them.

For LGB a Jumbo is the best option, I think. It is available for 110 and 220V.

Regards

Fred

ALL power supplies, including Bridgewerks and LGB Jumbos, have had issues and it is very frustrating to choose an adequate low-ripple DC power supply that is friendly to our motors! It is a great irony that a long-time company like MRC, whose middle initial stands for RECTIFIER, apparently cannot produce a low-ripple product in this digital age! VERY frustrating!  😐

Another option would be the LGB 5 amp controller and associated switching type power supply - less expensive than the JUMBO! Anyone here had any experience with one of those?

Also, has anyone here tried a laboratory grade, regulated and variable output DC power supply with a TRUE, low-ripple output? They are available in different price ranges on Amazon and most have digital volt and amp displays. Just wondering?

THANKS in advance for your comments and advice!  ☺

I am hoping we have a few EE's on the forum that can help!

Tinplate Art posted:

Also, has anyone here tried a laboratory grade, regulated and variable output DC power supply with a TRUE, low-ripple output? 

Yes I have, but the one I have is max 1A at 16V so I cannot use it for LGB. I use it for H0 and 0 trains. As you can see in the picture, right of the Lionel ZW, it has analogue V and A meters. Non DCC trains with modern motors really like it. Most of these types, including the one I have, however do not have a direction switch so I just added one (the small switch on the top of the casing).

Regards

Fred

Fred: THANKS!  ☺

How about power supplies from a hobby which needs low ripple power:  ham radio?

DOMINIC: Amazon Prime has quite a selection of both linear and switchable, regulated DC power supplies for just under $100 that have a low ripple output and are variable up to 30 volts with a current draw of up to 10 amps that should perform better than a "power pack".

Tinplate Art posted:

ALL power supplies, including Bridgewerks and LGB Jumbos, have had issues and it is very frustrating to choose an adequate low-ripple DC power supply that is friendly to our motors! It is a great irony that a long-time company like MRC, whose middle initial stands for RECTIFIER, apparently cannot produce a low-ripple product in this digital age! VERY frustrating!  😐

What exactly are the "issues" with Bridgewerks??

Super clean DC can be pulled from any car battery. By using 2 old used in series would get you 24V and can be re-charged by green solar or wind driven chargers. Properly fused and include a rheostat into the wiring would be best possible source of clean DC.

I decided to go with a regulated, switchable and filtered DC power supply: EVENTEK KPS3010D with a variable voltage output from 0-30 volts at 10 amps max. This unit has low ripple, a low operating temperature, a small footprint and a weight of 4 pounds at a price of $85, considerably cheaper than the comparable Piko units at $240 or the LGB units at $290! I should note that I only run single LGB locos with twin motors plus a few lights, so the 10 amp unit should be more than adequate.

I will report the performance of the EVENTEC unit after I have had a chance to use it next week.

Ripple in a DC power supply in North America will be 120 HZ. How is this affecting your engines? It should actually help operation as the peak voltage is higher than the average voltage and better at overcoming issues from dirty track. 

Many modern power packs actually add pulse width modulated signal with the DC voltage at the lower settings. 

If you think smooth DC will be better go to ebay and look for Kepco or HP lab power supplies. You will find many high quality ones under 50 bucks and all you need is a DPDT switch for reversing.

Pete

Pete and C. Jones: THANK YOU for your informed responses! I have some OCD and admit I have been over-thinking this whole power issue! When I first started with LGB in 1978, I, like many, did not have access to an LGB power pack and went with an MRC unit. I later learned that many MRC units employed some form of pulse in their output that was harmful to the LGB motors (overheating?). Later MRC units such as the Controlmaster 20 purported to have had close to a "flatline" DC output, and my LGB twin motor locos such as the 0-6-6-0 Mallet and the RhB Kroc, both with digital sound, ran quite well with this unit. I presently have both the same digital sound #414 Kroc and a 2085D Mallet, and went with the MRC Power G, for the extra capacity voltage (0-22) and current (10 amps), and that very cool smooth throttle. I also added an outboard LGB European steam digital sound system, which does not kick in at the lower voltage output when starting the engine with the Power G, so it is not quite in sync with the engine speed (???). I started to wonder if the Power G relatively unfiltered output may be the problem. So, I started to investigate the possibility of acquiring either the Piko or LGB 5 amp control units with their respective switching-type DC power supplies at a cost of either $240 or $290 respectively. Then I started to look into generic DC power supplies such as the EVENTEC unit which I purchased new from Amazon for $85. It has a regulated, variable voltage output of 0-30 and a current capacity of up to 10 amps, which should suit my needs of running only one twin motor LGB engine at a time. I am also hoping the digital sound will be more in sync with the engine startup voltage. That is my rationale for this thread, which did start out as a query about the performance of the MRC Power G, which by some accounts, may be a discontinued item from their product line. In general, I have had good results and smooth operation of both my Kroc and the 2085D, but I have also heard about the overheating tendency of the front articulated motor on the Mallet, so I wanted the best possible DC voltage for it. Now that I have fully explained my goals, is there any additional advice or corrections to my explanation? THANKS for everyone's patience with my musings! Your responses have been helpful!  

The EVENTEK DC power supply was a total bust! Right out of the box, there was NO voltage output as registered first by the digital LED voltmeter display, and later by my own digital MM! I double and triple checked the AC input leads and the DC outlet leads and everything checked out and no matter how I turned the fine and coarse pots, there was zit, nada, no DC output voltage! They are sending me a UPS return label and I will receive a full credit. Must be an internal fuse or open circuit. I will probably go with either the Piko or LGB 5 amp controllers. Maybe this unit was damaged in transit, but who really knows what happened!  😐

I decided to try another regulated, switchable DC power supply from Jameco Electronics in CA. They handle quality merchandise and offer a warranty on the products they sell. I got a 0-30 volt, 3 amp unit that should fit my needs. Very nice folks in both the ordering and technical departments who knowledgably answered all my questuons, and I would recommend them for your electronic needs!

On the EVENTEK supply, did you adjust the current controls? The current control limits the output current and if turned down to zero the power supply will not deliver any voltage output regardless to the setting of the voltage controls. - That's the usual problem my EE students have during their labs. With no load, adjust the current pots for the highest current output, then adjust the voltage output.

The purpose of current limiting is to limit the short circuit current.

LAD: I cannot swear that I did not adjust the current pots as you have explained, but that might very well have been the case! OMG! This new unit is very similar, so I will be certain to take your advice! THANK YOU!

In fairness, a note to Eventek about the mistake might be in order..?

  It may save a Q.C. tech some time, they may change the literature, etc..; Seems they delt fairly; I cut companies like that all the breaks I feel I can

ADRIATIC: GOOD points, and their manual was pretty minimalist compared to the one online for my new unit. I did explain to the Eventek tech guy what I had done, and he agreed that it was defective, and authorized its return. 

.

. You may have even mentioned that, it was a reactionary reponse; I put myself at a tech desk. 

As is, his play now. 

You could use a postwar AC train transformer and run the output of the transformer through a bridge rectifier.

I am not familiar with the ins and outs of LGB. What is the issue with ripple? Does it make the sound system crazy?

One consideration is that LGB motors are less likely to overheat with low-ripple DC.

I use a Bridgewerks Mag 15 with an LGB controller. It works great. I had an Aristocraft pcm controller, and it didn't work well with LGB. 

George

GEORGE: Interesting - I might feed the output of my Jameco unit into an LGB or PIKO 5 amp Controller

Problem solved: The low ripple DC Lab Switching Mode Power Supply (0-30V, 0-3 A) made by Velleman and distributed By Jameco Electronics out of California works great. Two 26" lighted coaches plus a lighted 24" dining car pulled by an LGB 2085D 0-6-6-0 mallet with operating smoke unit plus an outboard digital European steam sounds module and capacitance storage circuit operated well at 13 volts with a current draw of 2 amps with the Velleman unit. I plan to input a 24 volt output of this unit into a Piko 0-22 volt, 5 amp analog controller so I will have a larger speed control knob and also a reverse function without having to wire in a DPDT. My reason for choosing the Piko analog controller over the comparably priced LGB unit is that, unlike the LGB unit which requires a barrel-type voltage input plug, the Piko accepts stripped wires instead.

My MRC Power G has now become a surplus/backup power supply. Although it seemingly performed well for me, I was concerned about its relatively unregulated output. I am pondering whether to keep it or put it up for sale. At present, it is sitting on my desk across from my train layout.

So what you're saying is a Velleman switch mode power supply for $99.89 coupled to a Piko 35002 pulse width controller priced at $199.99 combined for $291.94 will produce 3 amps of clean ripple free DC power better than the MRC Power G or a $229.89 Bridgewerks Morrison power supply??

Wait a minute, the Pico controller is pulse width modulated? PWM is much harder on a DC motor than simple full wave rectified unfiltered sine waves. The rise time of the square wave is much faster than a 60 hz sine wave which means there is a greater lag between time voltage is applied to the windings and when the motor is able to accelerate due to that increase. The counter emf takes longer to build up (rpm dependent) so winding current is greater, hence more energy lost as heat.

Pete

C. Jones: I assumed the Piko analog throttle (5 amp version) would NOT have a pulsed output much like the corresponding LGB 5 amp electronic controller? My rudimentary understanding is that the pulsed DC output is what should be avoided with LGB 7-pole Buehler motors.

Pete: It seems illogical for BOTH Piko and LGB to have pulse modulated throttles when the goal is as flat line (low ripple) DC as possible going to their motors! Avoiding heat buildup is especially important with sealed motor blocks used by both Piko and LGB! Is it possible Mr. Jones might be mistaken about this?

I am getting a nice smooth DC output from the lab quality power supply. I would like a larger throttle and the ability to reverse, which the Velleman unit lacks.  

Guess I will just have to call a tech at Piko to clarify this issue. I will keep you all posted!  ☺

Clarification: Earlier, the Piko tech catogorically stated the Piko 35002 5 amp analog throttle does NOT have a pulse modulated output! Paired with my low ripple DC power supply, I should be able to have the smooth operation I am getting from the benchtop supply alone, but with a larger dial and reverse capability. I am a happy camper!  ☺

Also, I actually paid LESS than the prices quoted above by Mr. Jones for both the Velleman unit and the Piko 35002 controller. Cost was not a major consideration, just performance!

To each his/her own! Its all good!  ☺ THANKS for everyone's input!