I recently purchased a cheap multimeter from HF just to experiment with. When I plug the leads into an outlet it reads 120 +/- volts. However, when I check the terminals on the back of the CW-80, it reads 13 to 14 +/- at full throttle with no load. Is that right or is the multimeter off that much? I thought I should be seeing 16 to 18.
Larry
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Try it with a small load too like a blub...although it sounds like lionel has seen it before. Wonder if it's something to do with syncing the potentiometer to the handle?
The Bob Nelson CW voltage deciphering chart for use with Harbor Freight & similar meters:
The RMS voltage should be 18 volts; but your meter should read a little more than 15 volts. Here is a chart for converting meter readings to RMS voltage:
Meter RMS
0 0
0.5 1.6
1 2.7
1.5 3.7
2 4.6
2.5 5.4
3 6.1
3.5 6.9
4 7.5
4.5 8.2
5 8.8
5.5 9.5
6 10
6.5 10.6
7 11.2
7.5 11.7
8 12.2
8.5 12.7
9 13.2
9.5 13.7
10 14.1
10.5 14.6
11 15
11.5 15.4
12 15.8
12.5 16.2
13 16.6
13.5 16.9
14 17.3
14.5 17.6
15 17.9
15.5 18.2
16 18.5
16.5 18.8
17 19
17.5 19.3
18 19.5
18.5 19.7
19 19.8
19.5 19.9
20 20
One problem is that your meter is designed to measure sine-wave AC voltage, which is not what the CW80 puts out. Nevertheless, a reading of 12 volts should mean that your actual RMS voltage is around 16 volts; so something else may be wrong. Are you giving the CW80 the full 120 volts that it probably expects? American power-line ("mains") voltage is often archaicly described as 110 volts, but hasn't been that low for over half a century. Your meter might also be a little off, which could explain some of the missing 2 volts.
Bob Nelson
It appears there is nothing wrong with your CW-80 if it is otherwise operating fine.
I think that is rational advice, but if you turn the handle up all the way the error should be small as Bob's graph shows. Unloaded on the CW80 I get a consistant 16.8 to 16.9 vac with a Fluke 87 meter which is true rms reading, BUT with a small load on the CW80 I get a full volt higher. Roughly 17.9 vac rms. this was true for four CW80s. My load is a 250ma, 18v bulb. I think a small load is required for best measuring of a triac type regulating circuit.
I think with a small load, if the vac is not 17.5 vac or a little higher your transformer is lacking some. Your call if it's not adequate for your needs.
My trains have all run fine on them (CW80s), and I have had no problem getting my meters to read 18 V with no load. If you call Lionel customer service and your CW 80 is not too old, they will probably replace it like mine. Mine was a model G.
Flash,
These are the most sensible posts I've seen in some time. Keep up the good sense.
wolverine
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