Re: Large Gauge Ground Wire in Parallel with Loconet Gound Wires == Groundloop?
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Hi Mark, sorry for the slow response.
So as requested I've taken a few measurements and I'm a little surprised by the results, but it certainly explains a few things. My results are in the redish colour.
If you have an ohm better, check if there is continuity between the ground terminal and the metal case.
My result, I removed a case screw and stuck the probe into the thread due to all the metal having a black "coating". The measured resistance between the thread and the ground pin on the front connector was 6.8 ohms.
The next step is to measure electrical continuity between the ground terminal and the loconet ground pins 3 and 4.
My result, to my surprise 74Kohms. Yes 74,000 ohms! This was measured between the ground pin on the front connector and the middle conductors of a dummy loconet cable.
Measurements were taken with a Fluke 1587 and the booster was totally disconnected from the layout and power supply.
On Monday, 8 January 2018, 10:46, "Mark Gurries gurriesm@... [WiringForDCC]" wrote:
I have no first hand experience with the new systems. I am not sure what has changed with the new systems. The documentation of the new system promotes the ground wire as a AC Earth ground connection which makes no sense since it assumes that they have a safety liability situation which they do not. They are not making the AC power supply which does have a liability situation and cannot be legally be sold unless it addresses that safety issue per UL, ETL or equivalent safety agency requirement.
Anyway, if it is intended as a Earth Ground connection, then it must be connected to the metal chassis.
If you have an ohm better, check if there is continuity between the ground terminal and the metal case. There should be if supposed to fulfill its safety requirement.
The next step is to measure electrical continuity between the ground terminal and the loconet ground pins 3 and 4. I know there is on the older Digitrax systems. I measured it and you know it works because your suing the large ground wire with the older systems. If the new system BREAKS that continuity, that would explain why the large ground wire does not work and you must relay on the Digitrax Loconet ground for the booster common function.