I have a Lionel LW transformer that I just acquired. I like it, and at 125w it seems to be just right for one of the main lines on my layout. Does anyone know if the circuit breaker in these older transformers are reliable? Also, how do I verify that this transformer is in phase with my newer MTH Z-1000?
Considering that most Postwar Lionel transformers are at least 50 years old, I personally would not trust the breaker in them, even when new they took several seconds to trip. Simplest solution is to use an inline fuse-- for the LW, i'd use a 5 amp ATO (automotive) type fuse. Why 5 amps? the LW's 125 watt rating is input power. The output power is about 60-70% of the input, so you get about 80 watts-- 18V x 4.5 amps = 80 watts. The fuse won't blow unless you get upwards of 8 amps, even then it will take 2 or 3 seconds.
I'm not too familar with the LW's output setup-- I've never phased one of them. Hopefully, someone else will post the correct procedure--- I don't want to give you the wrong information---
A Day Without Trains is a Day Wasted
Thanks for your answer. So does this mean that a postwar Lionel LW would be roughly equal to a CW80 in output wattage? Where would I locate the fuse? On the hot to the lockon? Based on what I've been reading, the LW may not be such a bargain after all. I may just use if for powering accessories. It does have a nice fixed 14w post and also a fixed 18w post as well.
I agree that the post war transformers need better circuit protection, but a fuse keeps needing replacing, so I like circuit breakers-which can be reset.
The correct place for a fuse or circuit breaker is just after the hot terminal between the transformer and the lockon, or power distribution point.
Another thing that will help on newer engines with electronic circuits is a TVS; transiant voltage protector put into the circuit. Bob Nelson mentioned about using these.
Lee F.
Where would the circuit breakers and Transient Voltage units be available? Scott's Odds 'n Ends?
I picked up my circuit breaker at NAPA Auto Parts for $12.00. Put it right at old breaker but with heavy train the light came on then got dim as train started then set breaker off. With light plastic engine it worked ok, I'm going to check power cord then try to bring up my old forum chat Type TW transformer with Bob Nelson.
If I remember correctly, the circuit breakers in postwar transformers are there to protect the transformer, not what it is running.
A self resetting circuit breaker from some source like NAPA wired into the 'hot' wire between the transformer and the track and a transient voltage supressor wired across the 'hot' and 'neutral' wires will go a long way towards protecting what is on the track.
I'll let some of the more electrically skilled members chime in on the proper sizing of the circuit breakers and TVS.
Good luck.
8ntruck If I remember correctly, the circuit breakers in postwar transformers are there to protect the transformer, not what it is running. A self resetting circuit breaker from some source like NAPA wired into the 'hot' wire between the transformer and the track and a transient voltage supressor wired across the 'hot' and 'neutral' wires will go a long way towards protecting what is on the track. I'll let some of the more electrically skilled members chime in on the proper sizing of the circuit breakers and TVS. Good luck.
I remember that one from Bob! I also seem to recall he said they are not that quick to pop.
Jack
IF IT WON'T COME LOOSE BY TAPPING ON IT, DON'T TRY TO FORCE IT. USE A BIGGER HAMMER.
The 10 amp circuit breaker should be enuff power for any size train. A quick calculation at 18 volts times 10 amps puts you at 180 watts, that is more than plenty to run any train! 7 amps would be plenty of power as well.
In my opion a 15 amp breaker would make toast of any new equipment.
As bob Nelson mentioned, the circuit breaker in a postwar ZW was on the return side or common side of the transformer to prevent the transformer from overloading, NOT your trains! I will verify that it takes a direct short for three seconds or longer to pop the postwar ZW's circuit breaker, that is more than plenty of time to fry a new circuit board.
Also have heard it mentioned that the prewar & postwar transformers put out some kind of electronic white noise, which may be harmful for newer electronics.
RockIsland52 8ntruck If I remember correctly, the circuit breakers in postwar transformers are there to protect the transformer, not what it is running. A self resetting circuit breaker from some source like NAPA wired into the 'hot' wire between the transformer and the track and a transient voltage supressor wired across the 'hot' and 'neutral' wires will go a long way towards protecting what is on the track. I'll let some of the more electrically skilled members chime in on the proper sizing of the circuit breakers and TVS. Good luck. I remember that one from Bob! I also seem to recall he said they are not that quick to pop. Jack
Now that you mention it, I did learn that from Bob.
I run a PW ZW and have bus fuses in between the transformer and my tracks. I also have installed TVS modules to protect the electronics in my trains, these are at the power drops. I have had zero problems with electronics in my trains and I have had my fair share of derailments and popped fuses.
There is nothing wrong with using a properly serviced PW transformer for your layout.
Charlie a.k.a. MichiganRailRoad714 (Charter Member TTC)
I like the PW but I agree that I need additional protection. Do you use TMCC, Legacy or DCS with the PW? I have ordered 10 amp breakers from Scotts Odds 'N Ends. As I understand it, these go on the hot lead to the track. Scotts also sells TVS units, would there be any other supplier to recommend? When you say the TVS units go at the power drops, would that be between the transfomer and the TIU? So, for example, following the hot from the transformer it would be TRANSFORMER -> BREAKER -> TVS -> TIU -> TRACK. Would you agree? THANKS!
I use Legacy/TMCC for command. The fuses go on the hot leads in between the transformer and the track. The TVS modules go after the fuses at the power drops.
The TVS modules connect the hot to the common. The ones I have open up on voltage over 25 volts and send the spike to the common, away from your trains.
From my understanding TIU's have TVS technology built right in.
My Setup is TRANSFORMER -> FUSE -> TVS -> TRACK
Here is how Scott at Scott's Odd's 'n Ends recommends hooking up TVS
CONV: TRANSFORMER-> TVS-> FUSEBLOCK-> TRACK
TMCC: TRANSFORMER-> GRND CONNECTION FROM CMD BASE-> TVS-> FUSEBLOCK-> TRACK
DCS: : TRANSFORMER-> TIU-> TVS-> FUSEBLOCK-> TRACK
COMBO TMCC + DCS: TRANSFORMER-> TIU-> CONNECTION TO CMD BASE-> TVS-> FUSEBLOCK-> TRACK
Is it true the the MTH DCS TIU has TVS built in to it? I have not added DCS yet but was planning to in order to use Railking PS2. Also, is it true that a DCS can only handle 200W input per TIU? If so, is an LW, rated at 125 watts over the limit for a DCS TIU or is it not because the LW is not really 125W by today's standards?
At this time I do not know whether to buy another LW with TVS and fuses, or a postwar ZW, again with TVS and fuses, or just 2 MTH Z-1000s (which have manual breakers that I believe are a bit slow). I don't even know where to begin with modern Lionel except that I do not like the CW80.
I really appreciate you're input on this. Thanks.
To clarify my question about TIU wattage limit. I have one LW and am considering adding another. Each LW would supply the TIU, or in theory, 250W through the TIU. So if the TIU has an upper limit of 200W, wouldn't that exceed the limit and thereby toast the TIU?
I've had many derailments with modern command locomotives. I've never had any issue with my setup. I do question the assertion that the TVS should be placed before the breaker or fuses. What about a transient voltage spike due to a derailment? Having the TVS so far away from the power drop does not address this type of mishap, especially for other locomotives sitting at the ready on your layout.
So if running conventional you would advise this:
TRANSFORMER-> FUSE BLOCK-> TVS-> TRACK
right?
Simbo69TRANSFORMER-> FUSE BLOCK-> TVS-> TRACK
This is what I do for both Conventional and Legacy/TMCC
First, the output power of an LW is equivalent to an MTH Z-750-- about 75 watts. Each TIU channel is capable of handling 10 amps. The newest versions have fuses inside for each channel. Transient protection is in the TIU. I use a Z-4000 which has excellent overcurrent protection-- it electronically limits the output to 180W, so if you set the output higher than 18v, you get less than 10 amps--
HTH---
It doesn't much matter where the TVS is located. Its purpose is to clip the voltage spikes that occur when the transformer's magnetic field collapses after each short circuit, especially the numerous ones that occur during a derailment. You can do that right at the transformer or anywhere between the transformer and the locomotive.
The TVS should be connected between the two sides of the circuit. I don't see any point to the overpriced ones sold as an assembly that connect one from each side of the circuit to ground.
Remember in sizing your TVS that the normal peak voltage is 40 percent higher than the RMS track voltage, and that it's good to allow a safety margin above that to account for the tolerance in the TVS's and the transformer's voltage ratings.
Bob Nelson
Thank you to all who have contributed to this discussion about external (external to the transformer) protections.
My LTS suggested I trade in my Type ZW (275 watts) which I got in the mid 1950s for one of their used/refurbished ones, saying it might be more cost effective. At $250-$300 for another used one less my exchange, I'm not so sure.
Other than needing a power cord, the larger/major right hand throttle (most heavily used) seems to have lost its graduating precision 0-12 volts so that operating at lower speeds is at times frustrating to modulate. I run nothing other than postwar. In my terminology, they said the "rheostat windings" are probably worn and need replacing, not just a simple cleaning and adjustment.
I think I will just pay the piper, have them repair it, and keep what I have. This store has always been totally reasonable (price-wise), thorough, competent, and as anal about cosmetics as I am when I have had engines serviced in the past.
Jack, there is no rheostat in a ZW (or any other Lionel transformer that I know of). The carbon roller rolls over a section of the secondary winding, which is very heavy copper wire in that transformer.and unlikely ever to wear out. If it did, you would need to replace the entire transformer proper inside the "transformer" box. It is likely that your intermittent operation at some speeds is due to a worn carbon roller, which has reduced the pressure with which the roller makes contact with the winding. The fix replacing the roller(s), is a routine repair and no big deal. Cleaning is nothing more than wiping or brushing off the carbon powder left on the winding by the wearing of the rollers and only worth doing if the box is open anyway (to replace the rollers), since the powder isn't likely to affect operation.
Thanks, Bob. I think I will listen to you, keep it, and get it serviced. I can feel each incremental "click" in the voltage range as the throttle is moved, but some of them don't seem to add power.
Jack.
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