I have a KW transformer, without the instruction manual. I am not familair with these.
For accessories, is the 14 volts obtained by connecting the accessories to both the C+D posts, and not using a ground?
I checked the posts with a volt meter and they produce the following voltages:
U+C = 6.8 volts
C+D = 12.5 volts (back of transformer say 14 volts)
U+D = 19.5 volts (back of transformer says 18 volts)
Is it normal for these transformers to have voltages from posts C+D and U+D be above or below the voltage specified?
KW
On Variable voltage[railpower] using**“U” as Common** the A and B posts are 6-20 volts and for fixed voltage[accessories,etc,] with “U” as Common C is 6 volts and D is 20 volts.
Variable voltage with "C "as Common the A and B posts are 0-14 volts. For fixed voltage with “C” as Common the D post is 14 volts and U is 6 volts.
p.s:
What many call"ground" is really the Common or neutral return to the transformer secondary.
Here’s what I measured on my KW (no load):
AC Output:
A-U: 7.0 – 19.46 (should be 6 – 20)
B-U: 7.0 – 19.45 (should be 6 – 20)
C-U: 6.80 (should be 6)
D-U: 19.44 (should be 20)
A-C: 1.82 (should be 0)
B-C: 1.98 (should be 0)
D-C: 12.47 (should be 14)
So, based on your measurements and mine, I would say yes. Note that the 18V spec you saw on the KW is a 20V spec in Lionel’s service manual, so even the specs are somewhat questionable.
Leonard:
For some reason I wasn’t thinking correctly. I kept thinking of physical grounding instead of returning. Your using the word “common” and your P.S. brought it home.
Chris F:
Thanks for your meter readings.
I measured variable posts on my KW (without load), and arrived at numbers extremely close to yours.
Posts A-C, and B-C should be the lower power variable 0-14 volts posts.