Is it necessary to use 10 amp breakers in line when you are using a z1000 brick that has a 6 amp breaker built in. I am using the brick to power building lights ,and lighted towers and direct power to switches. Thanks Tstark
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A 10 amp breaker is for a 180 watt power supply. It will not provide any protection on a 100 watt power supply. You could add a 5 or 6 amp breaker or fast acting fuse in-line. The point of doing so would be to only do it if the breaker or fuse is faster than the breaker in the brick. The Z1000 has a fast breaker, but I have heard there are faster ones. Not sure you have much risk in leaving it out since you aren't using it for track power.
George
Seeing as the Z-1000's internal breaker is only 6 Amps, and the transformer is rated to deliver 5.5 amps continuously, a 10 amp breaker will never trip. If you want an added breaker, something in the 4-5 amp range would be suitable, but unnecessary. I WOULD, however recommend at least placing a fuse directly on the hot-side terminal of the accessory output of the brick if you are using the accessory output, as with the Z1000 there is an un-fused path between the track and accessory hot side connections if they are shorted.
JGL
Thank you both for your quick reply. I will add a fuse link to each z1000 brick Tstark
JohnGaltLine posted:... I WOULD, however recommend at least placing a fuse directly on the hot-side terminal of the accessory output of the brick if you are using the accessory output...
I don't understand everyone's preoccupation with fuses. Can you elaborate on this?
Rob,
I agree never really understood it either, I want something resettable, not something I need to replace.
PCRR/Dave
Sure, Rob. Seeing as no one that I've seen here has complained about melting their layout with a short between the Accessory and track sides on the Z1000 I am assuming it is not a common thing to be shorted out. I'd place an 8 amp fuse there because it costs pennies to protect from an uncommon short, and let the built in 6 amp breaker handle any normal shorts.
JGL
We had problems on the club layout in days past of "frying " electronics in both Lionel and Mth engines.
One of our members who is a newely graduated Electrical Engineer, purchase one of the new PXS Smart Breakers, we tried it and then purchased 2 more to cover all of our circuits, and TIU.
So far we don't have problems when derailments or shorting across tracks with tools, or what ever's.
I guess, I was probably the hardest to convince of the club members, but now I'm a believer of the PXS Smart Breakers as well!.........Brandy!
I'm a believer in the PXS-AC's as well. A PSX-AC is about 1/5 or less the cost of having the electronics replaced in just one engine. To each their own, but I certainly like them.
Brandy,
What was the cost of the PXS Smart Breakers that your young engineer purchased. My understanding is they are very good, but very expensive also.
PCRR/Dave
JohnGaltLine posted:Sure, Rob. Seeing as no one that I've seen here has complained about melting their layout with a short between the Accessory and track sides on the Z1000 I am assuming it is not a common thing to be shorted out. I'd place an 8 amp fuse there because it costs pennies to protect from an uncommon short, and let the built in 6 amp breaker handle any normal shorts.
JGL
So it's a cost issue as to why not a circuit breaker?
The pack/brick already has overload protection at 6 amps. I don't believe an 8 amp fuse will provide any further protection.
ADCX Rob posted:So it's a cost issue as to why not a circuit breaker?
The pack/brick already has overload protection at 6 amps. I don't believe an 8 amp fuse will provide any further protection.
Rob,
This is exactly why I suggest an 8 amp fuse. If you read what I wrote, it is for a very speciffic case on the Z1000 transformer, where in, the internal breaker provides no protection in the event of a short between the 'hot' side of the 14VAC accessory output and the 'Hot' side of the track output. The breaker is on the common to both of these outputs. As you are rather knowledgable about things, I know you are aware of this same problem in, for example, a post war ZW where a short can form between posts when the throttles are set to different levels. I suggest an 8 amp fuse so that it will NOT blow in the event of a typical short between Hot and Common, the built in 6 amp breaker taking care of what it is intended to do, However, in the event of an uncommon short between the two Hot outputs the 8 amp fuse will provide some protection. You can use a breaker if you like, but I don't see the point in spending extra cash on a CYA breaker that is unlikely to be blown by most folks unless they have faulty wiring on their layout.
JGL
Pine Creek Railroad posted:Brandy,
What was the cost of the PXS Smart Breakers that your young engineer purchased. My understanding is they are very good, but very expensive also.
PCRR/Dave
Not all that expensive, they are around $49.95 each. I think Charles Ro may have had them a little cheaper a while back, not sure what they sell them for now? I don't think C. Ro stocked them back when I got mine. IMO, that's pretty cheap when compared to replacing just one engine's electronics.
More info about them here: PSX-AC
Brandy,
Thanks much for the info.
PCRR/Dave
JohnGaltLine posted:However, in the event of an uncommon short between the two Hot outputs the 8 amp fuse will provide some protection.
I get all that, but somebody should check with an ammeter the current of a dead short between the outputs, as that core will struggle to reach anything close to 8 amps at 4 volts. Even on a ZW, with no other load and a difference of 5 volts between throttle settings, the current is only 5 amps and an 8 amp fuse won't blow until a 6 volt difference is reached.
Rob, I was unaware that the current would be limited in such a way. Quite honestly I'll have to stick my amp meter between the connections in question to determine how much current can be provided by the transformer. Also worth noting that this current will be driven through the Z-controller if the short is going through it. Assuming the transformer can not provide enough current between the two hot connections to pop an 8, or 7 amp, or whatever fuse, then I am forced to change my initial response and say that a 5 to 6 amp breaker is required on the hot side of each of the z1000's outputs if both outputs are in use.
JGL
Back to your original post -
If the wiring that you use for lights and towers is lighter gauge and can't handle 6 amps without damage, you should provide additional lower-current protection to the fanouts to these loads.
Dale Manquen posted:Back to your original post -
If the wiring that you use for lights and towers is lighter gauge and can't handle 6 amps without damage, you should provide additional lower-current protection to the fanouts to these loads.
This is a very good point. The size of the breaker is dependent on the circuit and wire gauge being protected, not the power of the transformer. The transformer sets the top end, but you may need a lower amp breaker.
JGL, now we are on the same page on this.
This is where you really want something like a #91 breaker(adjustable) if this is a genuine concern, guessing at a fuse size wouldn't cut it.
Based on the architecture of the Z-1000, my guess would be that MTH anticipated such a scenario and decided that a 2-3 amp fault current wouldn't do any damage and wouldn't need any further built-in protection.
I like to run two or three engines on one line with DCS and 10a fuses on the ZW; so what is the best power/fuse/breaker combination for my setup, especially if I run passenger cars?
Wally
I agree with Rob about the 91s......they are incredible.
-Roger
Cho Cho Wally posted:I like to run two or three engines on one line with DCS and 10a fuses on the ZW; so what is the best power/fuse/breaker combination for my setup, especially if I run passenger cars?
Wally
If cost is of no concern, I think it is generally agreed around here that the PSX-AC electronic breaker is the best thing currently available. Running only one channel it is also a fairly cost-effective solution for your application.
You will also want to have at least a few TVS diodes spread around your layout, and it doesn't hurt to have a lot of them. Folks often place one at each feeder to the track.
If the $50 price of the PSX scares you off, I would use a 7 amp thermal breaker rather than 10 amp. I think the reasons were discussed earlier in this thread. You typically want to use the lowest current breaker that will not trip when running your trains.
If you have access to an amp meter, place one in line between the ZW and TIU, and run your trains. See how much current they draw as they traverse the layout, and choose your breaker to be slightly higher than the highest reading you see.
As Dale pointed out, this all assumes your layout wiring can handle the current. if not, you'll want to choose a breaker based on what your layout can safely deliver.
JGL
I have utililized #16 braided "speaker" wire for all my feed lines for my DCS @ 18V. Does that limit anything current-wise?
Wally
Wally,
The answer is: technically yes, but practically no. 16 gauge wire, speaker or otherwise is good for about 9.5 amps. This IS affected by the length of the wire, but unless you have a very large layout this won't be of much concern. I would take the above advice on using a 7 amp breaker right off the transformer, and you will be fine with the 16 gauge wire. It is worth noting that the ZW you mentioned in the previous post can deliver more current than 16 gauge wire is rated to handle, so you will want a breaker to protect the wiring. With a typical Bus wired layout with 16 gauge feeders and 12-14 gauge main bus wire you won't really have a problem, as two or more feeders will be supplying the current to the track, however as you mention DCS, and you may have the 'recommended' "star-Wiring" setup, it is worthwhile to note that with that method of wiring there is only one feeder supplying power to a single block at a time. This shouldn't be an issue still, as DCS engines are not normally going to be drawing anywhere close to the limits of the 16 gauge wire, but if you run 4 dual-motor engines MU'd together, you will want to monitor how much current you are drawing through any single feeder.
Of course, if you run a 7 amp breaker or less, it will trip before you have to worry about your wire.
As a note on speaker wire, there is no practical difference with regular line cord, lamp cord, or such when used for the 18VAC or so in layout wiring. it is not recommended, however, for line voltage. Speaker wire's insulation is typically only rated for 80-100V loads where as line cord is rated for 400V+. It IS theoretically possible that a high quality speaker wire may be better for DCS than simple line cord, as high end speaker wire is designed to pass high frequencies better, but this is only applicable to very high frequencies over 10MHz. I know that the TIU sends out data as fast as its hardware can, but I think this is still in the KHz range, so I doubt any measurable difference would be noted.
Short answer: Use a 7 amp breaker right off the ZW, and you're fine.
JGL
Wally,
The only thing it will more than likely effect is your older Lionel Conventional Engines when they need more power, your 16 Gauge might be a little light for longevity running. If you have the Z4K and side receiver, it probably might not matter to much, if you run conventional thru the TR Z4K mode. JGL is correct if you are using the old ZW, the 7 Amp Breakers on each of your Red lines going to your In Channels of your TIU will work fine! I have 7 & 10 Amp Resettable Breakers in front of my different Transformers, never have had any trouble at all.
PCRR/Dave
Dave, I only run DCS PSd 2 and 3 on the ZW left handle circuit; I do run a Chessie Steam Special 8003 w/ the passenger cars on the right-hand circuit. I've never noticed any overheating but I'm going to check the current draw just to be sure.
Wally
Wally,
You may never have any kind of problem, I was speaking of Longevity running, which you may not really do, on a home layout. I was putting that in there, in case you run your Trains a for a long time period, as they do when set up at the Train shows.
PCRR/Dave
ADCX Rob posted:JohnGaltLine posted:However, in the event of an uncommon short between the two Hot outputs the 8 amp fuse will provide some protection.I get all that, but somebody should check with an ammeter the current of a dead short between the outputs, as that core will struggle to reach anything close to 8 amps at 4 volts. Even on a ZW, with no other load and a difference of 5 volts between throttle settings, the current is only 5 amps and an 8 amp fuse won't blow until a 6 volt difference is reached.
If you want to protect the accessory output of a Z-1000, a breaker with a rating of 5 amps will work. Any higher then 5 amps and the breaker won't pop!
The voltage difference don't mean that much to a fuse or circuit breaker, rather it is the load on the breaker that matters.
A comment about the breaker on a post war ZW, it is 15 amps on the common side, why on the common? It's a Lionel design. So it is best to add in circuit breakers or fuses around 7 or 8 amps at the output terminals A, B, C, and D to protect your circuits. Also don't forget to add in a TVS unit as they are inexpensive but worth the money!
Lee Fritz
A comment on wire; there is no difference between stranded and solid wire of the same wire gauge, they both handle the same amount of current. The only difference is how flexible one wire is over the other type of wire.
Lamp cord or speaker wire is rated by wire gauge, the reason for using a different name is to charge a different price because it is basically the same kind of wire.
Lee Fritz
phillyreading posted:If you want to protect the accessory output of a Z-1000, a breaker with a rating of 5 amps will work. Any higher then 5 amps and the breaker won't pop!
So the question remains, if you short the acc secondary output of a Z-1000(14 volts) to the track power output secondary(18 volts), between which there is no overload protection, what amperage will the transformer core deliver? If it makes you feel more comfortable, ignore the voltages I have listed, as these are fixed taps and will be the same among all examples of the Z-1000. The current is the number we are interested in.
OK - Some facts from measurements, done according to NEMA standards.
Z-1000 brick, Primary voltage @ 120VAC
18V short-circuit current at controller end of cord - 72A - breaker in brick trips
14V short circuit current at brick - 124.8A - breaker in brick trips
14V hot at brick to 18V hot at end of cord - 66.7A - breaker in brick does not trip
Note that these tests assume 120VAC available at the outlet, in ordinary usage these faults will pull the primary voltage down considerably due to resistance in house wiring, resulting in reduced short-circuit current levels.
Tests were not made through the controller head, these results are based strictly on the transformer and line and load cables. I do not know the magnitude of any additional current limiting provided by the controller head.
Now you're talkin'...
IF you look at the peak instantaneous current on a scope... now what about continuous? There's no way that core is capable of 66.7 amps at 4 volts(almost 270 watts) continuous.
At least, if we adopt your findings as presented, it is very obvious how problematic that unprotected fault current can be.
I can't confirm 66.7 amps. I can confirm over 26 amps constant... or at least until the insulation on my alligator clip starts to get toasty and I pull it off... about 15 seconds.
My "good" meter's highest range is 20 amps and the current is off scale. I had to use a clamp meter to get the needed range for the test, that meter reporting over 26 amps.
Whether the 66 Amps PLC is reporting, or the 26 Amps I am, placing a 8-10Amp fuse seems like a nice cheap solution to keep from melting your layout with an unlikely, uncommon type of short.
https://www.youtube.com/watch?...amp;feature=youtu.be
JGL
JohnGaltLine posted:I can't confirm 66.7 amps. I can confirm over 26 amps constant... or at least until the insulation on my alligator clip starts to get toasty and I pull it off... about 15 seconds.
My "good" meter's highest range is 20 amps and the current is off scale. I had to use a clamp meter to get the needed range for the test, that meter reporting over 26 amps.
Whether the 66 Amps PLC is reporting, or the 26 Amps I am, placing a 8-10Amp fuse seems like a nice cheap solution to keep from melting your layout with an unlikely, uncommon type of short.
JGL
If you want to experiment, try it again without the multimeter in the circuit; use only the clamp-on. The burden resistor in the DMM is in all likelihood the highest resistance in the circuit, limiting the current.
A fuse or breaker does seem to be in order if you are worried about shorts between the accessory terminal and the 18 volt supply.
FWIW, the "brute force" approach to measuring short-circuit current like that is hard, it is tough on the transformer and hard to get repeatable results due to all the rapid heating in the conductors. But, just for giggles, I will try it that way tomorrow and see what I get.
PLCProf,
You're probably right that the meter is adding resistance, but I don't know that it is going to be enough to matter when addressing how much current the transformer is going to deliver with a short. From a scientific stand point, there is a huge difference between our results, but from a practical stand point we both have the same results, A fuse is needed if you want to avoid the chance of melting your layout and starting a fire.
As I think about the issue it does make some sense that this is the result of the test. The brick puts out 100 watts (or so). What does it care if it is 5 amps at 20VAC, or 20 amps at 5 VAC? I'm sure that's not the correct math, but it seems to line up well enough.
After doing the test, it seems my reply was garbage. With an alligator clip from hot on the barrel jack to hot on the accessory post I saw over 50 amps on the clamp meter before burning my fingers and melting the alligator clip's insulation.
Net result is still, if you want to avoid burning your house down, put a fuse on the hots.
JGL
ChoCho & JohnGalt. There is a difference between what wire is safe and what wire is good for the application. Too thin a wire may still not be overheating, but cause voltage drop. Given the low voltages at which we operate trains, even a slight voltage loss can create an operating problem.
phillyreading posted:A comment on wire; there is no difference between stranded and solid wire of the same wire gauge, they both handle the same amount of current. The only difference is how flexible one wire is over the other type of wire.
Lamp cord or speaker wire is rated by wire gauge, the reason for using a different name is to charge a different price because it is basically the same kind of wire.
Lee Fritz
This is not strictly true. For applications in layout wiring, yes, there is no difference in solid or stranded wire, or in lamp cord and speaker wire. Scientifically speaking, there is more to it than that.
The difference that matters for most folks is that the insulation on speaker wire is not safe for line level voltages. You can use lamp cord as speaker wire, but you can't use speaker wire as lamp cord. For 18VAC or so track power, you can use either.
RJR,
Sure, if you are expecting to be running near the wire gauge's limits you probably want to use thicker wire. Again, with traditional bus wiring you never have a single wire handling the full load. With DCS 'star wiring' I might think about using 14 gauge feeders, if I was running 7+ amp trains.
JGL
Beg pardon John, but on my layout the common bus carries the full load. I do use 14-gauge for block feeds.
Pine Creek Railroad posted:Brandy,
What was the cost of the PXS Smart Breakers that your young engineer purchased. My understanding is they are very good, but very expensive also.
PCRR/Dave
Sorry I didn't see your question to me Pine Creek!
I questioned Nick about the costs of the 3 PXS' breakers and they were $90.00 for the 3 of them. I didn't think to ask him where he bought them, but may have been a supplier that he uses in his daily work?
If you want I can find out that as well???
I do know that with the flexible #12 stranded wire, and male/female gold banana plugs, a small wood box, with Lexan Cover, and vent screens, the club has about $150.00 invested. The vent screens maybe an over kill, but I built the box for protection from "drinks and "spit cups".
I'd like to see how some of our members live at home, on second thought, "No I wouldn't".
RJR posted:Beg pardon John, but on my layout the common bus carries the full load. I do use 14-gauge for block feeds.
If I'm not following you here... Sorry?
Assuming you're not ever drawing more than say 8 or 9 amps through it, 16 gauge wire is fine. If you ARE drawing 8+ amps, on a regular basis, you will probably want to use 14 gauge wire. To bring it around to the original topic a little, if you are running 10 amp breakers because 7 or 8 amp breakers trip under load, then yes, you want 14 gauge wiring. if you have a 7 amp breaker and it never trips, than 16 gauge is more than enough.
JGL
