ZW Accessory Help?

[laz 57]

Hi Guys,
Can anyone tell me what an accessory limit would be for a 180 watt power block on a ZW transformer? I am running 3 trains all have a 180 watt power block and the accessories off another 180 watt power block. I have noticed no problems but the C nut is getting quite hot after about 1 hour of use. Do I have too many lights and accessories on it? Suggestions?
Thanks,
Laz 57

[wrmcclellan]

Laz 57,

Two reasons the terminal may be getting hot:

1) Connection is not tight. Although you may be well within the current limit of the 180W brick, a poor connection offers high resistance and thus the connection will heat up with high current flow. So check your external connection and make sure it is tight.

2) There is also a slight chance that the internal connection in the ZW may be loose (or poor). I do not have a new ZW so I cannot comment on how the internal connection to the C terminal is made.

Since you are not tripping the breaker on the brick, you are probably within its current limits (basically 10 amps at 18 volts).

Each accessory pulls a different level of current. Since one rarely runs all of them at the same time - you could have more accessories attached than what maximum load calculations would show. Accessories have lights (thus load all the time), motors (load when running), and solenoids (load when activiated).

There are many very low cost ($12-20) multimeters (volts - ohms - amperes) on the market today. If you have one, measure the current (AC) and see where you stand with various combinations of accessories activated.

Regards,
Roy

[laz 57]

Hi Roy.
Thanks for the info I will put a volt meter accross the C terminal and the negative to night to see whats going on. If there is a drop off in volts should I get another transformer to help with the load?
Laz 57

[wrmcclellan]

Laz 57,

If you have a meter - make a current measurement (if it has AC current capability). The voltage drop across the terminal may be difficult to pinpoint.

Another approach, try disconnecting half of your accessories and see if the heating decreases (after making sure connections are tight and it still gets hot).

If it decreases, then another transformer to power some accessories may be the answer.

To make the current measurements with the meter if it has AC current capability (usually a symbol on the meter such as "~A"), plut the leads in series with the accessory load. Most meters require you to use a different plug (typ fused for 10 amps BTW) on the meter for amperes vs the plug you use for volts. So you could connect the red meter lead to the ZW C terminal and the black meter lead to the wire to the accessories.

BTW - are you just clamping the wire under the terminal or are you using a crimp connector on the wire to the terminal? Sometimes crimp connectors grip on the wire gets loose.

Regards,
Roy

[lionelsoni]

You might have trouble finding an AC ammeter suitable for measuring the load current. In any case, the current could be reasonable and the connection still bad. Measuring the load voltage to common (U) won't tell you much, since there should be some drop from the open-circuit voltage even if everything is normal.

From what I can see in the repair drawings, the terminal has a ring lug riveted onto the back of the binding post. The connection between the ring lug and the binding post is where the problem might be. See http://pictures.olsenstoy.com/cd/transfmr/psvw4.pdf

I suggest using the B terminal as a reference to measure the voltage drop on the C terminal under load. Remove the loads from both terminals. Then adjust the B output until there is no voltage between B and C. Then reconnect the load to the C terminal only and see whether any voltage appears. If it does, you have a bad connection in the C terminal.

Of course, you can measure the voltage across the terminal directly if you want to open up the transformer. If it is a bad connection, you will have to open it up to fix it anyway. I would first try to solder the ring lug to the terminal, so as not to rely on the riveting to keep them connected. I would then solder all the others while I was in there.

[wrmcclellan]

Hi Bob,

Do the new ZW's with external 180W power supplies (which Laz has) have the same internal connections to the binding posts?

I would note for the voltage load test you suggest using terminals B and C one needs to use the same exact load (accessory load) and 180W power supply (since they vary) for the test. This test may not work for the new ZW as each of the 4 outputs has its own independent voltage control circuit and thus one could get different results even if eveything is ok.

Regards,
Roy

[lionelsoni]

I know nothing about new ZWs, nor even that such a thing existed. If that's what he has, my test is certainly inappropriate. I was trying to use the B terminal as a connection, indirectly through the rollers on the secondary winding, to the ring lug. That won't work if that's not the way his transformer is built.

[wrmcclellan]

Hi Bob,

Lionel introduced a modern ZW a few years ago. It is optimized for TMCC, but runs conventional just fine. There is no transformer in the ZW, using up to 4 external AC power supplies (135W or 180W Powerhouses) that plug into the ZW case. Internal is circuitry similar to the TMCC PowerMaster track voltage controller, but can be controlled with TMCC Cab1 or the handles on the ZW. The new ZW if you get to examine one weighs nothing compared to the PW classic.

Thus with the 180W Powerhouses (4), one can supply approximately 10 amps to four circuits.

The unfortunate part is the output is a chopped sine wave (like the Powermaster output) and one has to contend with the ZW case and 4 heavy external Powerhouses that do not come with easy mounting capability (if you wanted to put them upsidedown on a frame under the layout). The good part is the Powerhouses have circuit breakers.

Regards,
Roy

[Anonymous]

Put you meter in the ac current mode and then connect one lead to the zw terminal that you have disconnected and the other lead of the meter to the wire you disconnected from the zw. You need to check current in series. Then watch your current load on the meter, especially when you are running the train.
If you have allot of passenger cars, the lights will suck current like crazy.
I sold a set of 9 aluminum up cars to a young fellow who put them on one of his main lines powered by a 180 watt brick and with the local pulling it the breaker tripped.
He has to limit his train to six cars.
He also has an extremely long main line and has no feeders to different parts of the track. He is relying on the lionel connector pins only to feed the oval main in a room 24 feet long. He has at least 48 feet plus the o72 curves of just track to feed
The cars have 4 18 volt bayonet bulbs in each one, so in the 9 car train,he has 36 bulbs being lit at 18 volts.

[laz 57]

Roy,
Thanks for the info I did put the wires in the crimp connectors so maybe one did in fact come loose, I will check them and see if there is a voltage drop with the volt meter.
Thanks guys,
Laz 57

[laz 57]

Thank you Guys,
After putting the test leads to the ZW I infact did have a voltage drop so I removed 15 lamp post lights to a 80 watt transformer, ran the ZW at full power fo 30 minutes and it did not heat up. I also made sure the nuts to the ZW were tight.
Thanks again,
Laz 57