Going rate for a lightly used ZW 275W in good condition?

JD,

   Around the Pittsburgh, Pa area the ZW 750  brings between $125.00 - $160.00 depending on how pristine the individual Transformer happens to be.  At the Train shows they go a might cheaper around $100.00, if the vendor wants to sell quickly.  I have also seen then go for around $200.00 if the vendor is using the ZW for more of a show piece than a sale item.  

O Gauge Jim here in the OGR sells his reconditioned ZW's for more than a reasonable price, and they work even better brand spanking new.

PCRR/Dave

Around $100 is good. I just bought one for $80 that was serviced.

Bob

Thank you for the feedback Dave and Bob.

 This is a tough question. You say the unit is slightly used. I’m not exactly sure what this means however remember the transformer is at least 50 years old and probably even more. Age can do a lot of things to electrical components. Rubber insulation can start to deteriorate, solder joints can start to fail from acid. Probbably if you examine the cord closely you will find some crazing through the rubber insulation to the copper conductor especially close to the plug or where the cord enters the transformer.

The chances are the rectifier discs in the whistle circuit no longer operate. If this is the case they should be changed out for stud type diode’s which is a tremendous upgrade in the technology required to blow a tender train whistle.

The transformer contains four carbon rollers which transfers the voltage from the transformer windings to your trains. If they have never been changed, no doubt by now they have deteriorated to the point that they either need changing or are very close to need changing. 

 The circuit breaker in the transformer is very critical. About half of the transformers I rebuild have circuit breaker’s that do not work  and need to be replaced. This accomplishes two things, one it gives you a circuit breaker that works and two I replace the circuit breaker with a much higher quality modern circuit breaker that is much more reliable. A couple of things you can do to enhance the value of the transformer when you sell it, assuming you are selling to a knowledgeable train collector, is first, check the voltage of each output. Each output should be at least 19.6 V and hopefully at least 20 V.  Keep in mind you can still get voltage readings if the carbon rollers are worn out. Instead of a roller going across the face of the transformer coil, you are sliding the copper arm which the roller fits on and you will still get the voltage but it will cause damage to the transformer coil.

Now check the circuit breaker.  Plug the transformer in and advance the A circuit handle to full voltage and use a screwdriver and put a short between the A terminal and a U terminal. You will hear a hum, the red light on the transformer will come on and within about five seconds you’ll hear a click which is the circuit breaker opening as it should.  If this doesn’t happen and there’s no click within say six or seven seconds remove your screwdriver and consider the circuit breaker defective.

Over the past few years I have reconditioned more transformers than I can remember and have yet to have a call back due to a problem.  I normally try to purchase my transformers for rebuild at train shows since there is no freight costs involved. If I came upon a ZW transformer such as you define as slightly used and the case was in very good condition, and the simple tasks outlined above had been done on it or I could do them myself before I purchased it, I would probably offer $60. If it was really cleaned and had no signs whatsoever of abuse, I might go to $70. As stated above, my offer would be based on the fact that I know inside that case there are many things that could be broken such as rollers, deteriorated insulation, “fried” rectifier discs and so forth which I would have to replace before reselling the unit.The unit could still pass the above tests I outlined in spite of many problems inside the unit that need to be addressed.

I have probably giving you a lot more information than you need, however I hope it will be helpful.

Have a great weekend,

Jim Lawson a.k.a. O Gauge Jim

Thank you, Jim. The information is very helpful. 

the most important thing Jim mentioned is true if the carbon rollers were never replaced there is a good probability that the roller is worn out and the copper arm that hold the carbon roller has cut threw the transformer winding even if only half way the transformer cannot to be repaired without changing the transformer itself. I have seen this and would never buy or sell one in that condition.!

I would take the tope off and inspect the carbon rollers and transformer winding for this condition!

Alan 

my hobby shop repairs and completely rebuilds the 275 zw's and then guarantees them to the seller, new rectifier stud diode new rollers replace any parts that are worn check or replace whistle push switch which sometimes goes bad and go over all solder connections!

Alan

So far, I have not seen a ZW whistle switch that could not be rebuilt. I've had a number of them that I had to disassemble to properly clean. Replacement rivets are available. They cost about $1.00 each.