I installed the Blunami Steam decoder into the tender of my LGB 20232. I purchased the decoder, battery and wiring harness from RLD Hobbies. All works fantastic. Is it possible to add another battery in a trialing car so that I can run off one battery and when it runs down switch to the second battery? Is it possible to plug into the tenders’ existing female jack so that I can accomplish this? Or would it need another harness switch to do this? The way the existing harness works is when the switch is up the loco receives power from the battery and will run. When the switch is down, I can plug the charger into the female jack and charge the battery. When the switch is in the center position the loco is OFF. Is it even possible to do what I want? Thanks
It can be done, but you would need to change the way the jack and switch are wired. The switch you currently have is likely a Single Pole Dual Throw with Center Off. To accommodate a second battery AND the charger being plugged into the jack would require changing the switch and how it is wired. You would need a Single Pole triple throw switch. The new switch still has three positions, but all three connect to different “throws”. This is a SP3T switch…
I need to study your picture of the existing switch to advise further on wiring, but it should be just a matter of replacing the swithc and changing how it’s wired,
Basically, the switch would be wired for 3 functions: A: power loco from Internal Battery B: Power loco from External Battery C: Charge internal battery (Blunami Off)
EDIT: Looking at your pics again,you have a Dual Pole Dual Throw (DPDT) switch there. I’d replace with a DP3T.
I’ve been doodling trying to come up with a wiring diagram for the DP3T with no success. Maybe a second switch would be easier. I’m tired and my brain isn’t sharp. If I come up with a way to wire it I’ll post. I know it’s possible as I’ve seen it done.
Yes it’s possible. The old wiring diagrams for the old RCS throttles show a wiring diagram using a DPDT switch to both use on board battery and then off/charge/input from extra battery. I have a paper copy laying around somewhere but maybe someone has a digital version.
Guys, you missed something. The second battery will need to be charged and switched off (isolated) just like the primary in the tender. Much simpler to set it up the same as the tender, with the RLD wiring rig. A DPDT in the tender and a DPDT in the trailing car, with the outputs to the motor wired together in parallel.
And of course you can use 2 batteries if they are identical. Nothing will happen if you turn them both on at once.
Timmy, what is unknown at this point is what you did inside the tender that affects the plug on the back. LGB uses it to send track power from the wheels to the coaches behind.
If it is still connected to the track pickups, which you have now isolated from the motor, then you will need to find the wires and connect them instead to the Blunami input, labeled Rail Pickup on your diagram.
And that’s the problem with this concept. Timmy, have you ever run long enough that the loco stopped as the BMS detected it was at the low discharge cut-off?
I’ve never had that happen with my locos.
P.S. another solution is to keep a fully charged spare battery handy and swap it with the one in the tender when you need to.
I’ve thought about setting up the trailing car exactly the same way as the tender is wired up and have both battery wires go to the Blunami.
I don’t know what wiring in parallel is.
Nothing is connected to track pickups as they are completely removed.
I have no idea what the BMS is.
I thought about keeping another battery fully charged however, that would require the time to take the tender apart remove the one battery and install the second. My desire is to run the train as long a possible.
That is what I do with most of my steam locos. The battery is under a removable coal load and has a plug so it’s quick to swap.
And to Peter’s point - I’ve never had a fully charged battery run out while using the loco. I generally get 4-5 different uses before I need to charge. I do not do roundy-round so one use is maybe 45 minutes total run time. Run time is dependent on battery capacity Vs loco current draw.
Here you go. This is the wiring diagram I’m talking about.
This is similar to what you currently have.
Timmy, having both battery wires go to the Blumani is wiring in parallel.
You haven’t been doing your homework. If you are going to play with Lithium batteries, you need to understand them.
The BMS is a Battery Management System. Small pcb that prevents over charge or over discharge, etc.
I recall describing it for you last year. Look it up and read about them.
No reason not to have another complete battery system. I just doubt you’ll ever need it.
@PeterT
I get the feeling you enjoy this…
The reasoning for thinking about a second battery is for my Christmas layout. I would like to keep the train running all day (or close to all day) without having to re-charge it.
If… the batteries are wired in Parallel, would both batteries then charge together from the existing single charge port?
That will work if both batteries are the same capacity (MAh). Wiring batteries in paralell maintains the same voltage but doubles the current and approximately doubles the tun time.
If you do this, fully charge both batteries before connecting them.
I don’t. I find it very frustrating answering the same questions every week. You could find most of the answer using google or the search here.
But as you are not the only person asking, I answer hoping the next guy will search before posting.
Google: “site:largescalecentral.com parallel”
Not a good idea. Jon’s reply was aimed at running the loco when in parallel (i.e. both switched to ‘on’.)
You would be better off wiring them with 2 separate charge ports. They’d take twice as long to charge if you try to do both at once, so you don’t gain anything. And (a) you can use the second battery with some other loco when this one gets hot and burns out from running around the tree all day, and (b) easier to debug any problems.
Pete - I disagree. Charging both at the same time will take no longer than charging each individually if you have only one charger. It’s not a problem for the batteries if they are the same brand / capacity. If the BMS of one battery shuts down early, the second will continue to charge, effectively balancing the two packs.
To your point about running around the tree - I agree. Tim, would be better off with track power for a continuous all-day run.
I’ve used track power since 2003 for my Christmas train, running it all day long. The issue is that as I’ve posted a number of times previously (dig at PeterT, if you search this site you would see this) my Christmas layout is a single mainline with a reverse loop at each end. Over the years the device I’ve been using to achieve the double reverse loop (which includes special wiring has given up the ghost. Last year I decided to try remote control / battery power with the Blunami 4408 decoder. It worked fantastically! I wish I had done this years ago! No special wiring, no blown fuses, no special device, zero issues except… I couldn’t run it all day long without taking a break to charge it back up.
@PeterT that is sad that it is very frustrating for you answering the same questions every week. It must be tough to be such a train guru/tzar.
I am a professional photographer for the past 30 years. I’ve taught numerous classes. I belong to numerous photography forums. I am pinged constantly with questions, many the same of how to do this, how to do that, how did I achieve this or that, etc. I don’t get frustrated with ANY of these questions. They wouldn’t be asking if they didn’t have a question and want to know and learn. Different people learn in different ways. I always respond when asked with simple to follow answers with details of ‘how to’.
I am NOT a train guru. And, at times I have questions of how to do this, or how to do that or is this possible or what if. I totally enjoy my trains but I am not uptight about them. And…believe it or not, I do search on most of my questions prior to posting in this forum or other train forums. However, much of the time, the search returns information that I may not understand…thus asking further.
If my questions as well as other people’s questions frustrate you…perhaps it’s best you don’t answer if you can’t answer without coming across as an arrogant know it all…
There are and were people here that would get upset with people for not searching for an answer to a question or other things like how to OPERATE your railroad. For the most part they have gone away or in a few cases Ben banned by BD. Sometimes when you need to know , it’s better to ask again than spend hours searching for a similar issue, find something then after reading several posts , find it’s not what you are looking for, again and again
Timmy,
I think you answered your own question. You don’t need to take a break but the train does. So pulling into the station for water/coaling tower OPERATIONS after a couple hours you could easily unplug and swap a freshly charged second battery to a trailing car like you asked in the original post. Trailing car solves a lot of complex problems and brings it back to simplicity?
Now trying to figure out how to run a massive Amtrak consist along with a triple headed modern freight consist all day long on batteries at Lionel speed is a serious challenge my friend. However it will do nothing but force you to drink beer and use narcotics. One must also remember to never use schedule II controlled substances while trying to solve that issue as you will want to save them to get everything up and running.
What narcotics do you have? I’ll bring whiskey. May I come visit you and Amtrak?