Z-4000 Transformer: Pulsing building lights

i believe when the transformer reaches a certain amp limit I believe the transformer automatically throttles back the current, but don't hold me this ? I would check with GGG George on the dcs train forum he can tell you for sure, I know he will know your answer for sure and good luck!

Alan

Is it possible there is a wire crossed somewhere? Have not tried to power lights off of a Z4000, got ahold of an older ZW for that.

 You're not exceeding the power. What you are experiencing is the transformer oscillating about it's set point. This instability varies with the load and setting. If the accessories output is appropriate for what you need it may be more stable. I've had the same issue with the CW80. It's most noticeable with lamp that vary brightness with a small voltage variation.

It's a common design goal to prevent oscillating but not always easy to accomplish.

It's remotely possible that there is some adjustment on the inside circuit board to reduce the feedback loop gain of the regulator. I doubt it, but one can hope. I think also that a lamp load which takes a finite time to warm up and increase it's resistance can lead to instability also because it then reduces the current slightly which cools off the lamp and causes the current to increase slightly...you get the picture. It might also help if you put some outboard resistance in series with the bulbs to decrease the effect and allow you to operate at a different (higher) voltage.

Thanks for the replies.

Chuck, how would I install outboard resistance? I don't know what this is?

John, I recently tried calling MTH service on another matter and was on hold for 20 minutes...gave up. They don't answer e-mails either. Very poor service.

Bobby, I doubt there's any wires crossed...since its happening on 4 different circuits.

Well that's just a thought if you had some various values of resistors to try in your parts box. The resistor value would be on the order of one ohm at say 10 watts if you are drawing 4 or 5 amps. The resistor would be in series with the lamp load. Like transformer A terminal to the resistor, the other end of the resistor to the lamp, the other end (common terminal) of the lamp to the U terminal.

What accessory voltages are available and did you try them?

Since lamps are basically resistors, adding more resistance to the supply legs will do nothing helpful.

Your best solution is to use a plain old transformer, one that does not have wonky bits inside.  I use a few ZW's for all my fixed A-C supplies, and a telephone company D-C supply for relays and signalling.

Arthur P. Bloom posted:

Since lamps are basically resistors, adding more resistance to the supply legs will do nothing helpful.

Your best solution is to use a plain old transformer, one that doe not have wonky bits inside.  I use a few ZW's for all my fixed A-C supplies, and a telephone company D-C supply for relays and signalling.

 

My thought was just to change the operating voltage to one that is stable and still have the desired illumination.

However, a different non-electronically controlled transformer will of course work, but that wasn't the question.

I suppose you could start disconnecting the  lights until the flickering stops.   I've seen this happen with the accessory posts  (overloaded) on  a  Z-4000. I was curious why you weren't using them .

Regarding the accessory posts...they're 10 and 14 volts each - haven't used them yet because I like to be able to dim the lights - however I can try the 10 and see what happens.

Is the new Lionel ZW-L any better for lighted buildings?

If you just power one of the terminal blocks at 4-5 amps and leave the other off, does it still pulse?   Each output is rated at 180Watts so your not exceeding a limit, but the common black terminals are connected inside the transformer.   G

Well, it's Deja vu time and I am just seeing the latest replies to this thread that I had started 4 years ago!

FWIW: I had solved the problem by adding more transformers and distributing the load to each, however I am in the same situation yet again. I suppose its my own fault, as I continue to add buildings with lights here and there around the layout thinking that one or two won't exceed limits, silly and hopeful me (think of the father in A Christmas Story where he has myriad Christmas lights plugged in the wall outlet). The amperage output per Z-4000 "handle" or side is between 5-6 amps, and given that I have two Z-4000s just for accessories/buildings that totals about 11-12 amps per transformer, which isn't good apparently. I guess I should've bought a couple of ZWs a while back when I had the chance, but at that time was broke. I will likely need to add yet another transformer just for accessory lighting! It is getting monotonous but building a fantasy world knows no bounds.

I had a similar circumstance with a Z-4000 ,  but had a radio tower with a blinking led.  Once I put that device on a separate wall wart the blinking of other lights stopped.

Marty

Interesting Marty. How many other accessory/lighting loads did you have on the Z-4000.

I do have a number of blinking light accessories...mostly Railking buildings with blinking signs, and bridge lights as I recall.

Paul,

   I had about 4 or 5 other incandescent lights that were lighted by the z4000.  I decided to light them all from a Lionel PW ZW and the blinking light from a separate wall wart.  Not sure if it was a fault of the electronics in the z4000 or the blinking light on the same post as the other lights

Marty