Power pack basics

[Kiran]

I have a couple of Kato power packs 22-018 and a couple of Tomix NCS 600s. Can I use them interchangeably with Unitrack or Finetrack? Are there converters so that I don't have to work with naked wires?

 

I made a double track layout today with a branch line from one of the tracks. It would have been great to be able to use the Kato power pack lying around. I had to dig out an ancient Tomix power pack from a bunch of old Tomix stuff that I got in an estate sale. Not sure what power pack it is but it makes my trains run really fast even at the lowest setting. The same rotor controls the throttle and direction.

 

Also, are there any power packs that have more than one controller? They start taking up space. Are there controllers with smaller profile?

 

I like the way Tomix feeders connect to the track. Is it possible to do the same with Unitrack? Having to add a feeder in a Unitrack layout means sometimes no flexibility in where your power pack and feeder go.

 

Thanks ever so much for information.

[katoftw]

You can use any power pack with any track.  But you will need to make you own power cable convertors.

[kvp]

First, i think the old Tomix pack is probably a pure 100V rheostat one, which is not safe, even on the 110V american voltage.

 

You can mix and match any pack to any track but you have to cut and splice wires. Although Kato sells screw terminal ended wires that doesn't need cutting. Tomix also had similar ones for but they are long discontinued.

 

For power feeds on unitrack, you can use feeder joiners to add power between any two tracks.

 

The new Tomix startset speed controllers are relatively small, but lack accessory power, so you'll need one full pack for that.

[Kiran]

On 10/14/2018 at 10:46 PM, kvp said:

First, i think the old Tomix pack is probably a pure 100V rheostat one, which is not safe, even on the 110V american voltage.

 

On 10/14/2018 at 10:46 PM, kvp said:

 

The new Tomix startset speed controllers are relatively small, but lack accessory power, so you'll need one full pack for that.

Can you please point me to the Tomix startset speed controllers? A quick search on Hobby Search didn't get me any but their search sometimes needs precise keywords.

 

I also found these. Could I use them perhaps to control 2-3 loops of track? I am guessing they will only control the direction and not the speed. But I can connect one of these to a power pack and control loops instead of just sections of track?

 

https://www.1999.co.jp/eng/10292927
https://www.1999.co.jp/eng/10292931

 

[Kiran]

Also, any recommendations for a simple power pack that I can buy in the US? Not looking for Kato but something that can connect wires.

[Gryphr]

This is Tomix' current lineup of powerpacks:

 

• N-600 - Basic Powerpack
• N-1001-CL - Powerpack with CL functionality (Constant Lighting, Trains equipped with compatible lighting can light up while stationary/moving slowly)
• N-DU101-CL - "One-Handle" Powerpack with CL functionality (Instead of a rotating knob this has a handle with several Power/Braking Steps like many modern trainsets and simulates acceleration/deceleration)
• N-WL10-CL - Powerpack with a Wireless Controller and CL functionality, has 2 Point Switches built in which can also be controlled using the remote, there's also a Black and a Red version
• N-DU204-CL - "Two-Handle" Powerpack with CL functionality (This has a Power and a Brake handle and is roughly modelled after the controls of older JNR-Era trainsets, simulates acceleration/deceleration, has 2 track power outputs)

Some Tomix Basic sets feature the "compact FG-17" power unit which is also a simple power pack like the N-600, but with less output current and without an accessory power interface.

Edited October 16, 2018 by Gryphr

[cteno4]

The simple powerpacks you find here in the us these days are usually the mrc powerpacks. The tech 7 have a single and dual. The single has a momentum function that when in will slowly build up the speed to the max you set on the throttle.

 

the only issues with these guys is they go up to 20v so you don’t want to go over about 2/3 of the throttle. Usually you can tell this fine as your trains will be flying off the tracks at that point. You can attach a simple and cheap digital volt meter on the power outputs (like $2 on ebay) to keep an eye on the upper end if you want.

 

They have screw terminals on the back so you can either just screw down twisted wire on them or get some simple spade connectors you can crimp onto the ends of the wires (just twisted braided wire will fall apart after a few screw downs and is a little fiddly to screw down at times.

 

we use the older version of the dual tech 7 for our club layout, they work great. You won’t get the constant light feature (CL) of Tomix lighting sets but the will turn on when running, the dual are nice for saving space.

 

https://www.modeltrainstuff.com/mrc-1278-tech-7-ampac-780-dual-action-train-control/

 

https://www.modeltrainstuff.com/mrc-1276-tech-7-ampac-760-train-control-with-momentum/

 

non dcc throttles in the us are getting scarce as so much is now dcc even with beginner sets.

 

jeff

[Kiran]

On 10/16/2018 at 12:36 PM, cteno4 said:

The simple powerpacks you find here in the us these days are usually the mrc powerpacks. The tech 7 have a single and dual. The single has a momentum function that when in will slowly build up the speed to the max you set on the throttle.

 

the only issues with these guys is they go up to 20v so you don’t want to go over about 2/3 of the throttle. Usually you can tell this fine as your trains will be flying off the tracks at that point. You can attach a simple and cheap digital volt meter on the power outputs (like $2 on ebay) to keep an eye on the upper end if you want.

 

They have screw terminals on the back so you can either just screw down twisted wire on them or get some simple spade connectors you can crimp onto the ends of the wires (just twisted braided wire will fall apart after a few screw downs and is a little fiddly to screw down at times.

 

we use the older version of the dual tech 7 for our club layout, they work great. You won’t get the constant light feature (CL) of Tomix lighting sets but the will turn on when running, the dual are nice for saving space.

 

https://www.modeltrainstuff.com/mrc-1278-tech-7-ampac-780-dual-action-train-control/

 

https://www.modeltrainstuff.com/mrc-1276-tech-7-ampac-760-train-control-with-momentum/

 

non dcc throttles in the us are getting scarce as so much is now dcc even with beginner sets.

 

jeff

Thank you Jeff. I now have the MRC Tech 7 dual and it works well. Solved my temporary power supply needs.

[cteno4]

Just don’t take them past like 2/3rds the way. Most n scale trains are about to fly off the tracks when you get them up to 12v.

 

You can hook a little digital voltmeter to the powerpacks to watch this

 

https://www.ebay.com/itm/Mini-DC2-5-30V-LED-Panel-Volt-Voltage-Meter-3-Digital-Display-Voltmeter-2-Wires/183124467723?hash=item2aa311a00b:m:m8T8X0y-WVrAmTjUPHWu4XQ

 

jeff

[kvp]

2 hours ago, cteno4 said:

Just don’t take them past like 2/3rds the way. Most n scale trains are about to fly off the tracks when you get them up to 12v.

So these are linear packs, not pwm? That would be ok in terms of track voltage but the running characteristics of the trains will be worse than with pwm packs. Perhaps comparable to the recently retired Kato transistor packs (that could also output H0 voltages in the red range when used with the official power bricks).

 

I would suggest getting japanese made packs for japanese trains, especially N scale as the overcurrent protection is set way too high in many american packs (could melt the trains and the turnouts high).

 

On the other hand, the added extra voltage might be needed to get DCC decoder equipped trains to full speed in analog conversion mode as those need around 14V to run as fast as an analog train at 12V.

[cteno4]

The mrc packs work fine for japanese trains, we have used various ones for the last 12+ years with the club.

 

jeff

[Kiran]

I am making sure that I don't go more than half way with the throttle on the MRC pack. The only trains that I run at full throttle are the Shinkansens and generally use the Kato/Tomix packs for those trains.

[sandiway]

On 10/28/2018 at 9:20 AM, cteno4 said:

You can hook a little digital voltmeter to the powerpacks to watch this

https://www.ebay.com/itm/Mini-DC2-5-30V-LED-Panel-Volt-Voltage-Meter-3-Digital-Display-Voltmeter-2-Wires/183124467723?hash=item2aa311a00b:m:m8T8X0y-WVrAmTjUPHWu4XQ

Wow, so cheap! I ordered 6.

[kvp]

1 hour ago, sandiway said:

Wow, so cheap! I ordered 6.

I'm pretty sure these can't handle reverse polarity, so never use reverse on the throttle when connected. Also the minimal voltage when it turns on is color dependent but it's somewhere around 'a bit too fast' and a bit below 'takeoff speed' for N scale. In short i think an accessory voltage powered, reverse polarity handling voltmeter would be better for this job.

 

Imho just marking the max safe speed on the throttle is a bit easier.

[sandiway]

5 hours ago, kvp said:

I'm pretty sure these can't handle reverse polarity, so never use reverse on the throttle when connected. Also the minimal voltage when it turns on is color dependent but it's somewhere around 'a bit too fast' and a bit below 'takeoff speed' for N scale. In short i think an accessory voltage powered, reverse polarity handling voltmeter would be better for this job.

Now you tell me! I ordered red because it had the lowest turn-on voltage.

 

i can use my regular multimeter first, but I am curious about voltage drop on my 8m long Shinkansen loop, where I run my 16 car N700A, hence my interest.

 

[kvp]

1 hour ago, sandiway said:

Now you tell me! I ordered red because it had the lowest turn-on voltage.

 

i can use my regular multimeter first, but I am curious about voltage drop on my 8m long Shinkansen loop, where I run my 16 car N700A, hence my interest.

Just add a series protection diode and add its forward voltage (0.6-0.7) to the measurement. They are so cheap that you can even add 2 back to back to measure in both directions.

 

ps: If you measure with a turning motor on the tracks, the feedback voltage from the motor will show too, superimposed on the track voltage.

[sandiway]

8 hours ago, kvp said:

Just add a series protection diode and add its forward voltage (0.6-0.7) to the measurement. They are so cheap that you can even add 2 back to back to measure in both directions.

 

ps: If you measure with a turning motor on the tracks, the feedback voltage from the motor will show too, superimposed on the track voltage.

To be clear, the total voltage will simply be lower (than without a moving train), right?

And if a train has two motors, the lowering should be doubled.

[cteno4]

I have a few of these and experimented with them a number of years ago and now I can’t remember if they are reverse polarity protected or not. I’ll dig them out and check. My memory sort of is they are and just didn’t register in reverse polarity. Fine as usually the poser pack is running one line in only one direction except for shunting and then voltage not needed

 

jeff

[kvp]

8 hours ago, sandiway said:

To be clear, the total voltage will simply be lower (than without a moving train), right?

And if a train has two motors, the lowering should be doubled.

Yes and no as the motors are in parallel, but a lower per motor physical load should mean a higer top speed and more speed dependent backemf, but it's not linear.

[sandiway]

31 minutes ago, kvp said:

Yes and no as the motors are in parallel, but a lower per motor physical load should mean a higer top speed and more speed dependent backemf, but it's not linear.

Two motors in parallel will see the same voltage but share half the available current.

Back-EMF is proportional to motor speed.

Shouldn't then this mean that a train with two motors (running at basically the same speed) be generating twice the back-EMF?

(Obviously you are an electronics expert, so this is a serious question.)

 

Edited November 5, 2018 by sandiway

[kvp]

3 hours ago, sandiway said:

Two motors in parallel will see the same voltage but share half the available current.

Back-EMF is proportional to motor speed.

Shouldn't then this mean that a train with two motors (running at basically the same speed) be generating twice the back-EMF?

(Obviously you are an electronics expert, so this is a serious question.)

Twice the backemf current but the backemf voltage would be just as much more as they are faster. So for a train to generate twice the backemf voltage, it has to move roughly twice as fast. Two motors are better, but usually you don't get doubled speed. If all your cars were motor cars, you would still get the same voltage at the same speed, but many times more current.

[sandiway]

24 minutes ago, kvp said:

Twice the backemf current but the backemf voltage would be just as much more as they are faster. So for a train to generate twice the backemf voltage, it has to move roughly twice as fast. Two motors are better, but usually you don't get doubled speed. If all your cars were motor cars, you would still get the same voltage at the same speed, but many times more current.

OK, duh! That makes perfect sense. Thanks!

 

The problem with adding the diode is that you get 0.7V drop. So the meters will read proportionally lower, right?

Edited November 5, 2018 by sandiway

[kvp]

39 minutes ago, sandiway said:

The problem with adding the diode is that you get 0.7V drop. So the meters will read proportionally lower, right?

Yes. Although Jeff has said they might already have them built in.