Adding external charging plug

Yes, it is a charging harness with the round port, a connector for 9V style battery and the 2 pin connector.   You have to install in an existing square hole or make your own.  I think the kit is $10.  I have one kit and plenty of harness if you need them.  E-mail in profile.  G

The kit is pn 50-1022 BTW.

Rod

One must be very careful when cutting the hole, so that the metal shavings don't jump to the speaker magnet.  Might be worthwhile to remove it.

Any ideas on how to most easily cut a square hole.  I don't want to use my square drills on metal.

I strip the chassis completely, then drill a hole as large as the sides of the square, then I use my small files to square the hole.

The key there is that you strip the chassis.  I hate removing all the stuff.

Wait a minute, guys.  If the loco is so old it doesn't have a charging port, it would be the 5-volt model.*  The 50-1022 is for that loco, BUT, isn't it a round hole?

*Unless it's an upgrade, during which the upgrader omitted installing the port.

I just use a BCR in these early PS2 engines without charging ports and I never have any battery problems again. Just like PS3 uses capacitors.

But where to cut the hole on a MTH J1e Hudson? Diesel seems straightforward(?). Maybe BCR is the way to go. What are the disadvantages of a capacitor other than waiting 30 seconds compared to a battery?

Waly

Wally, if the PS2 unit is in tender, as it is with most (but not all) MTH steamers, cut the hols in the tender floor is you can find room for the socket among the existing stuff, and can access the outside with the plug, avoiding the trucks.

Problem with the BCR is the cost if you have many locos.  I have 20, and over the years since DCS have only replaced 3 batteries (one on a used loco I bought).  That would be a lot of $$ for BCR's.  I don't think you have to wait 30 seconds if you have PS2---only PS1---but I'm sure someone will correct me if I'm wrong.

I've never put a charging plug in, if it needs a battery, I'll give it one of my home-rolled BCR clones.  The holes I make are for switches and volume controls and the like.

You actually do have to wait for the BCR to charge in a PS/2 locomotive, until they sit for a short time, they don't start up correctly.  I forgot I had a BCR clone in one and tried to start it right after turning on the power, and I thought it was broken.   This is a case where the battery appears "defective", and is worse than no battery for PS/2.

We're all different but i wonder if it's worth the effort to install a charging jack. After all a battery should last 4 or 5 years? maybe that's pushing it.  For the first time I tried a BCR  in one engine and it seems to work fine although I haven't tried changing any settings , IDs etc.

Some of our engine still have the white 9 volt (8.4) and will be replaced with BCRs.

gunrunner,, do you like the BCRs?

Gregg, depends on how often you run trains and have the loco on a powered-on track.  If you rarely run, batteries will need to be charged occasionally.  If you run a few times a week, should be ok.

I like the ones I build, I'm a cheapskate.   They work fine so far for me, but I have seen mention of some folks having issues with the charging circuit using a BCR.  I've been tempted to investigate a diode resistor combo to slow the charging down a bit, yet allow full current to flow out of the BCR.

If you consider the cost of a new battery, external charging kit and the time to install it, the BCR looks a lot better. Plus the constant opening up of the engine and the possibility of pinched wires and broken shell posts should also be considered. I've never encountered a charging problem using them in a MTH engine.

Years ago, I had a PS1 engine that wouldn't charge a battery and thinking a BCR would work, I installed it with the same results as the charging system wasn't working. I replace the bottom PS board and it has worked ever since with the BCR.

Recently, forum member GGG found the board had a bad trace on the board keeping it from charging and he was able to repair it.

I also have them in early PS2 engines with no charging port.

Couple points here.  While the charge port for a PS-2 5V is round, the mount is still square and fits in a square hole.

The port goes were the battery is.  So even on a Steam engine with board in the engine, if the battery is in the tender.   The battery connects to the harness in the tender.  So you put the port in the tender and plug the port into the spot the battery was plugged into, and then plug battery into the new port connection.

As far as BCR, John, I would not slow the charge rate.  I think one of the issues is the batttery is at 2.5V and the inductor is cycled to charge and provide an additional 2.5V to replace the 5VDC of the regulator when the AC power is cut.  When you put in a BCR at 0 volts and it charges to 5VDC you now have 5V available without the inductor.

I am not fully sure what is going on with the circuit, but as the BCR charges, the processor and audio amp are some what disabled.  Audio is cut in half, and you really don't have control of the engine.  At some point above 1.8 to 2.0V of BCR Charge the audio comes back along with control of the engine.  Since it was designed with a battery in mind, I think the less the time it sits in this low voltage charging state the better, but  that is only a judgement on my part.  G

My idea was to use a pretty low value resistor just to reduce the peak current, it probably wouldn't affect the charging time all that much.  I'm thinking on the order of 10 ohms or so.  The internal resistance of those supercaps when dead discharged is very low, that's what I was thinking about.

I have no idea how well the charging circuit actually limits current, which is why I floated the idea to get some input.

After the weekend I can send a diagram and maybe you can help me figure it out too:-) .  I have the basics, but it is an interesting circuit and the main processor is involved.  I think a pulsed FET also.  G

It takes a lot more analysis if they inject the processor into the mix, unless it's obvious what they're controlling with it. It would be interesting to have some insights as to what is going on.  Too bad that MTH doesn't have someone like Jon Z from Lionel dropping in occasionally to throw some light on topics like this.

I've seen a lot of oddball circuits for charging, if you think this is difficult, try charging a large multi-cell Lithium battery without blowing it up!

...and if you figure out the process, call Boeing.

The very last project I worked on before total retirement was a large Lithium battery for a business jet.  The first test of an overloaded cell was very spectacular, I was suitably impressed!  If you like fire and smoke, you'd have loved this test!   BTW, it's a year since I've been off the project, and they're still toiling away on the battery project, no end in sight last time I checked.   It has nine microprocessors, one monitoring every cell, and one master monitoring the whole battery.  A couple of 2,000 amp FETs were another interesting wrinkle as well.

Large Lithium batteries can go up in flames, and it's next to impossible to put them out until they burn out!  Nasty stuff.  I've seen two demos working with two different Lithium battery manufacturers that ended the same.  I only wish the videos weren't proprietary so I could have had them.

We use Lithium Polymer batteries in electric RC planes and you have to use a special charger for these that balances the charge for each cell. They also may explode in flames if damaged in a crash or shorted out. Definitely not good for a model train.

At least not for any of mine.