I realize that when running trains with either DCS or Command 18 volts is required. It seems that depending on the weight of the train or if running 2 engines at once or a passenger train with lights voltage can drop by as much as 5 volts. I am using an MTH Z4000to power my layout. Is there a way to have the 18 volts regulated so that no matter what the situation is there will be a steady 18 volts at all times. Thanks in advance.
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Well, with cruise control it shouldn't matter as much if there are small voltage changes. OTOH, if you're seeing a 5 volt drop, you have wiring issues! I just connected a Lionel PowerHouse 180, open circuit it showed 18.9 volts. With an 8.7 amp load, it dropped to 17 volts. A drop of five volts is excessive!
I pulled out the Z4000 and repeated the test. You have to discount the open-circuit voltage displayed on the Z4000, it's somewhat bogus. 22 volts is the actual voltage with a very light load, 50 ohms. With a 2.2 amp load, I'm seeing 21 volts, and with a 9 amp load on the channel, I get 19 volts out of the Z4000.
OG3RAIL posted:...if running 2 engines at once or a passenger train with lights voltage can drop by as much as 5 volts. I am using an MTH Z4000...
To be clear, is it the Z4000 voltage display dropping from 18V to 13V...or are you measuring these voltage drops using a meter at locations around the track?
No I am reading the display on the Z4000.
Like I said, with a 9 amp load on one handle (max is 10A), I get a voltage drop of 3 volts. 5V just seems excessive, does it happen if you use either handle connected to the same track?
I have not tried the other handle. I will have to check that. I should say its not always a 5V drop but it varies.
If you're seeing a 5V drop, IMO there's either something amiss with the Z4000, or you're drawing a lot of current, probably close to tripping the breaker.
I noticed if I set the Z4000 voltages using the 4000 remote device the voltage stays constant during operation, although the amps are limited to about 8 instead of 10. Setting the voltage with the Z4000 handles I see the voltage moving up and down as the trains operate, but the max amps are then 10+ ... What's the explanation for this happening?
Do you think putting an external volt meter on the transformers output would be more accurate?
If you put an external meter on the track connection, you can see what the track is actually seeing. However, if the Z4000 meter is dropping 5V under load, IMO something is wrong.
So if I am doing some light switching in the yard OR pulling a 20 car freight with an unpowered engine and one powered unit I should not have to adjust the output voltage on the transformer if I originally started by setting it to 18v with no load?
Like I said, we run six PH180 bricks on the club layout. Four are on four power districts on the mainline, the other two service sidings and accessories. We also have an old ZW that does some other yards, I've added modern circuit breakers to each output of that one. We never adjust the power on anything, and sometimes there are is a 10-11 car lighted passenger train and a long freight with 30-40 cars on the same power district. Nobody notices any issues. I've seen two long passenger trains follow each other around the loop, no power problems at all, much of the time they'd be on the same power district for a spell. Other than when we have a derailment, I can't remember the last time a breaker tripped.
OG3RAIL posted:So if I am doing some light switching in the yard OR pulling a 20 car freight with an unpowered engine and one powered unit I should not have to adjust the output voltage on the transformer if I originally started by setting it to 18v with no load?
No. Setting the Z-4000 at 18V no load is not near the maxim output and as the load (current draw) changes voltage will droop or lower. So set the no load voltage higher.
Are you seeing any issues operating your trains in command mode? If not, do not worry too much about the voltage. G
I think I'd put one locomotive on the track running at a reasonable 20-25 scale MPH on the track and adjust the output for 18 volts and stop worrying about the voltage. If you're still getting wild voltage swings, time to look at wiring.
If he is hitting 10+ amps, isn't he running into overloading the Z4000, which probably will cause the Z4000 to start cutting back on voltage? If he runs at a lower voltage, then maybe he can't draw 10+ amps and the voltage will be sustained.
Please describe what you are running that is drawing 10+ amps.
Yep Dale, he would be at 10+ amps. Hard to believe what he describes is a 10+ amp load, I have to believe it's something amiss somewhere. This is one of those things that would probably be easy to diagnose in person, but very hard in ASCII. 
No I am not drawing anywhere near 10 amps even using 2 engines to pull a train, but that is where I see the drop in voltage and start to have issues with the dcs and command . I think if I try GunnerJohns advice and set my transformer at 18 volts under an average load I should be ok.
How can you be so sure that you are not drawing 10+ amps if the meter on the Z4000 says you are? You might have a problem that is pulling the high current. Try the other handle and see if you get the same results.
Again I ask what is the makeup of the train?
No I never said that I was drawing an excessive amount of current I was just seeing a voltage drop when running 2 engines or pulling heavy trains which was causing my the engines to run erratically.But when I moved the handle on the Z4000 so that it was reading 18v again everything was fine.So the reason I asked the question was to find out if the Z4000 would regulate the output voltage.
No it does not have feedback and self regulation. Don't believe any trains transformers do unless some custom high-end product is out there. G
Didn't you state " Setting the voltage with the Z4000 handles I see the voltage moving up and down as the trains operate, but the max amps are then 10+ "? That is certainly overcurrent that could cause the output voltage to drop.
So I think if I try setting my voltage up under an average load like John advised That should solve the problem. Thanks For everyone's advice!! one more quick question if I am operate between lets say 16-20v should that be a problem?
Lionel Legacy and TMCC don't like more than 19 volts on the track. DCS should be fine with a few more volts of track voltage.
Dale, I think Kerrigan jumped in with the 10A comment.
Oops! Sorry!
No worries!!
gunrunnerjohn posted:If you put an external meter on the track connection, you can see what the track is actually seeing. However, if the Z4000 meter is dropping 5V under load, IMO something is wrong.
I use a meter at the actual point on the track where I want to see the voltage and then compare it to the voltage at the output of the Z4000. The difference I guess is what is sucked up by the wire and connector resistance.
gunrunnerjohn posted:Lionel Legacy and TMCC don't like more than 19 volts on the track. DCS should be fine with a few more volts of track voltage.
Dale, I think Kerrigan jumped in with the 10A comment.
I meant that with the voltage set by the 4000 remote, the breaker will trip at an 8amp load instead of the expected 10amps. Setting the voltage with the transformer handles the max amps before breaker trip will be 10amps, as expected for Z4000 max output amps.
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