BCR charge procedure

Hi RON,

  Just let the engine with BCR sit on the track for a minute or two.  Don’t start it up until the time period of a minute or two is up.  Easy and no more changing batteries.

It charges when the track is powered. Specifically though, on a PS2 engine, the sounds start off slightly reduced volume until the system detects he battery or BCR to be above a certain voltage so it is quite obvious when they suddenly get loud- indicates the BCR charged to the threshold voltage.

Sorry to resurrect a year-old thread but I made an interesting observation tonight while upgrading a PS2-3v engine with a a BCR. I decided to tap my meter into the now useless charge port and monitor the voltage increase as I applied power to the track and as this was on a DCS test track, the engine remained dark & silent.

The BCR charged very slowly, and after 2 minutes the new BCR only went from .7 to 1.1 volts. Nowhere near enough power to maintain a shutdown sequence.  Next, I hit the startup button, and the floodgates opened. Within seconds it went from 1.1 volts to 1.8 and after about 30 seconds it was at 3.4 volts.

I tested this on a couple of other engines and the result was the same. An engine that I hadn't run in a while had a depleted BCR with an initial voltage of 1.5 volts and at 3 minutes of full track power with the engine off, it was only up to 1.9 volts, at 9 minutes I finally reached 2.5 volts. Once I hit the start-up button, the BCR voltage increased significantly faster. After pressing the shutdown button the BCR voltage continued to climb rapidly to 4.8 volts and slowed as reached 4.9 volts which is normal behavior. The operating voltage of the BCR topped out at 5.055 volts after 15 minutes.

What I surmised from this is that placing your PS2-3v engine on an energized track (with DCS signal) while leaving it off (dark & silent) will result in very slow charging. You should at least start and shut down the engine to initiate the charging of a battery or BCR.

Not sure if the PS2-5v boards behave the same way, I didn't test those.

I am interested in buying BCRs for my PS2 engines. Is it correct that they will help both the 5 volt and 3-volt PS2 engines by eliminating the batteries? You simply plug them into the battery clips/plugs, and then let engine sit on track 2 minutes before  hitting startup on DCS remote?

And will they decrease the probability of failure of the 5-volt electronics that I read are notorious (is that the applicable word) for capacitors blowing up?

@Paul Kallus posted:

I am interested in buying BCRs for my PS2 engines. Is it correct that they will help both the 5 volt and 3-volt PS2 engines by eliminating the batteries? You simply plug them into the battery clips/plugs, and then let engine sit on track 2 minutes before  hitting startup on DCS remote?

And will they decrease the probability of failure of the 5-volt electronics that I read are notorious (is that the applicable word) for capacitors blowing up?

My first maintenance task when I buy these locos. I've read that the old white batteries are board killers. Contact GunrunnerJohn- he sells both the 9v style and newer PS2 3v.

@H1000- thanks for the added info. I've seen this happen with engines that I've just installed BCR's in but hadn't pinpointed the source/ cause of the condition.

Bob

@Paul Kallus posted:

I am interested in buying BCRs for my PS2 engines. Is it correct that they will help both the 5 volt and 3-volt PS2 engines by eliminating the batteries? You simply plug them into the battery clips/plugs, and then let engine sit on track 2 minutes before  hitting startup on DCS remote?

And will they decrease the probability of failure of the 5-volt electronics that I read are notorious (is that the applicable word) for capacitors blowing up?

Paul, the BCR's you would purchase for the 5-volt and 3-volt PS2 engines will eliminate the batteries that are currently in your PS2 engines. One needs to remove the batteries, as the BCR's utilize the battery clips/plugs to connect to. From past experiences, some of the PS2 battery locations take more work than others to access, in order to change out the battery to a BCR.

In regards to your last question, IMO the BCR does not affect the probability of a capacitor failure. If it's going to go, it will. The more savvy electronics guys on the forum can correct me, if I'm wrong on that. I have an MTH PRR Q-2 steam engine (5-volt board) that I changed the battery over to a BCR a long time ago. Recently, after a long period of being in the box, I put it on the track and increased the power to the track to power up the BCR. After about 20 seconds of power (above 10 volts) I heard the "pop" and saw some smoke as the capacitor had blown up. The engine now has a PS2/3 stacker board in it and it operates fine now.

There was some discussion about the additional surge current from the BCR causing premature failure of the 5V charging circuitry.  I haven't personally seen it, and I do see a lot of 5V boards come by with BCR's.

As for the BCR causing the capacitor failures, I can't see how that would happen, it sure doesn't make any sense to me.  Even if the BCR were causing some premature component failure, the components things like diodes and/or regulators that actually have to pass the excessive current, not capacitors.

I have 4 PS2 engines with super caps I installed using Gunrunnerjohn's recommendations. Two are run solo, two are in MUs with PS3 engines. I usually turn on track power and then push Startup, with little delay. Everything works fine, except the PS3 engines are notorious for missing the watchdog and starting in conventional.

@John H posted:

Everything works fine, except the PS3 engines are notorious for missing the watchdog and starting in conventional.

I ran into this also. I've never taken time to research it extensively but I power my tracks with the Variable outputs but they are not set to fixed voltage output. My engines Would miss the watchdog signal when I turn on the bricks or turn the variable outputs on (set at 22 volts starting voltage). So I set the variable outputs to a starting voltage of 21.5 and then bump them to full power of 22 volts. Never missed a watchdog since.

@H1000 posted:

What I surmised from this is that placing your PS2-3v engine on an energized track (with DCS signal) while leaving it off (dark & silent) will result in very slow charging. You should at least start and shut down the engine to initiate the charging of a battery or BCR.

Maybe a dumb question.  But if I don't plan on installing or using a TIU, how is the charging handled in conventional?  How long does it take to reach the target voltage?  Thanks for researching this and posting about it!

@Ted S posted:

Maybe a dumb question.  But if I don't plan on installing or using a TIU, how is the charging handled in conventional?  How long does it take to reach the target voltage?  Thanks for researching this and posting about it!

Ted, I read your message while on the workbench so I just tested it. As soon as you start to hear sound from the loco, the rapid charging begins!

How long it takes to reach the target voltage depends on the charge state of your BCR before starting your engine. From 1.5 volts to 3.5 volts will take about a minute and that is sufficient voltage to keep the electronics and sounds on for 10 seconds to complete the shutdown cycle.

Some additional FYI information about PS2-3v behaviors at different (BCR) voltage levels:

1.6 volts - not enough power to run the sounds and electronics - sounds will cut off early and the board won't completely shut down.
1.9 volts - The DCS remote indicates the Battery as "LOW" The engine sounds go from normal to quiet during track power down.
2.3 volts - The engine sounds go from quiet to normal during commanded start-up.
2.9 volts - Minimum voltage in the BCR needed to complete a successful track power down (with sound), using the BCR indicated below.
3.3 volts - This one is odd. When powering down a DCS track, a "dark & silent" engine won't drop below this voltage level. Not sure if the electronics shut down prematurely or if something else is going on. Any DCS "dark & silent" power down below this voltage results in very little to no voltage drop of the BCR.
4.0 volts - The DCS remote indicates the Battery as "HIGH"
5.1 volts - Maximum volts observed in the BCR after 90 minutes of running.

The DCS remote will indicate Battery "OK" between 1.9 and 3.9 volts.
This was tested with a 5.0v 2.5uF BCR, results with other BCR capacitance or an actual battery will be different.