BroadwayLionAnytime you establish a comon return...
BroadwayLionOK, LION has not DCC, obviously the DCC is not participating in a common return, but the system should be plugged into the wall with a three prong plug and trust the manufacturer to do whatever it is he needs to do inside of the box.
The original question was about DCC, where you yourself said there is no common return. Did you read your own post?
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carl425Just to add my 2 cents to what Bob has said, the "ground" in this case is the "safety ground" that keeps line voltage off the chassis. This is the 3rd prong on your electrical cord. Since the power supply is the only place in the system where 120 volts is present, it is the only place where this ground is useful.
Not so. Anytime you establish a comon return you run the risk of having stray voltage on it. This can cause unpredicatble behavior and make the whole thing next to impossible to troubleshoot. GROUNDING the comon return wipes these voltages off of the bus, and will clear many gremlins from your system. If something "funny" is going on, the first thing I check is to be sure that my ground bus is in fact correctly grounded to earth.
Here is MASTER GROUND for Route of LION .
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
cmrproductsWhile that was recommended at one time - the current thinking/recommendation is to NOT gound the system other than at the Transformer/Power Supply.
Just to add my 2 cents to what Bob has said, the "ground" in this case is the "safety ground" that keeps line voltage off the chassis. This is the 3rd prong on your electrical cord. Since the power supply is the only place in the system where 120 volts is present, it is the only place where this ground is useful.
LION recommends a HARD GROUND.
LION has several different power supplies. A floating common has its problems since stray voltages will make their home there and make trouble shooting almost impossible.
Thus the common is a HARD GROUND, all stray voltages will go away.
OK, LION has not DCC, obviously the DCC is not participating in a common return, but the system should be plugged into the wall with a three prong plug and trust the manufacturer to do whatever it is he needs to do inside of the box.
LION has a 10.2 volt regulated power supply putting out 12 amps to the tracks.
The LION attached the negative post to GROUND, and the Positive to the railroad. On the Railroad, the LEFT rail is grounded and power is applied to the right rail. Obviously for YOUR application you will need to do things differently, but since subway trains do NOT run backwards, it is not necessary to worry about reverse operations. LION has plans for that eventuality.
The Tortoise power system consists of two DC supplies, the + of 1 is connected to the - of 2, and this is GROUNDED. This leaves the LION with +12; -12 and 24v dc outputs. Tortoise machines are connected to GROUND and to the "Stinger" that is the circuit that drives the turnout, - = normal; + = reverse.
The SIGNAL / Track Detection system has a 16v dc transformer, neg=ground, pos to the system.
The AUX system is 12v dc, neg=ground; pos lighing circuits.
With all of this you can see why the common must be GROUNDED.
OK, YOUR railroad is not this complicated, but good practice suggests that your common must be Grounded.
While that was recommended at one time - the current thinking/recommendation is to NOT gound the system other than at the Transformer/Power Supply.
Only a common wire between the Command Station and Boosters as well as any other components that show a Ground (which in these cases is a COMMON).
BOB H - Clarion, PA
Actually, Digitrax does recommend connecting to an earth ground at one point in the system, usually the command station/booster. They also note the difference between a common and a ground. See the last paragraph here:
http://www.digitrax.com/tsd/KB352/powering-your-digitrax-command-control-railroad/
"Ground" and "Common". Many confuse those terms.
Another example is in a DCC decoder. Common is the plus voltage.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
Don't.
If you have multiple components, they do need to be tied together with a common line so they all have the same reference, and in the case of Loconet, excessive currents that may flow between two boosters in separate power districts when a locomotive bridges the gap.
But do not connect those items to an earth ground. The low voltage side of the power supply is isolated from the high voltage and doing that defeats the purpose.
I have seen a few places where people are recommending you "ground" your Central Station or Booster. Where exactly are people grounding too? Does installing a GFI outlet help this issue and/or eliminate the need for grounding? Any thoughts on basic electronic safety and DCC would be appreicated. Christian