Hello All:
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Just an FYI.
On 24.1.1, I added a hierarchical connector named RTN, and conductors, to route a net that was connected ground (GND) (node 0), out of a hierarchical schematic to permit connection of that net on a top level schematic to ground or possibly some other net.
Outside the hierarchical block I connected the RTN label through a resistor to a triangular (label 0) ground symbol.
After running the sim, pointing at the net connected to the ground symbol says "This is ground."
Pointing at the net on the opposite side of the resistor says "Click to plot V(n030)".
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Inside the block, the RTN hierarchical connector and the attached net both have the V(n030) net name.
Inside the block, I restore the triangular (label 0) ground symbol and re-connect it to the net having that V(n030) net name.
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After running the sim, nothing changes outside the block, still ground on one side of the resistor and V(n030) on the other side connected to the RTN hierarchical connector.
Inside the block, the RTN hierarchical connector still says "Click to plot V(n030)" but, the net connected to that RTN hierarchical connector now says "This is ground."
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The resistor outside the block has one end connected to ground and its other end also connected to ground through a hierarchical connector named RTN.
That resistor should now disappear from the netlist but, it does not.
Pointing at the resistor still shows the "plot my current" arrow and the net that goes to ground through the hierarchical connector RTN still says "Click to plot V(n030)".
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Since LTspice's ground (GND) (node 0) is a perfect superconductor that never drops any voltage, there can never be any current through that resistor because it is grounded on both ends.
It should not show a "plot my current" arrow when pointed at.
It says that the resistor has a DC operating point of -36.724039uA and 13.486551nW.
It says that V(n030) = -367.2404uV. It's a 10 ohm resistor.
LTspice becomes confused in this example.
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When no hierarchy is involved:
A resistor grounded on both ends is removed from the netlist hence, it shows no "plot my current" arrow when pointed at.
A resistor grounded on one end with the other end unconnected or connected to an open wire, is also removed from the netlist.
Neither resistor's current nor the open net's voltage can be plotted.
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If I remove the resistor and connect the RTN label directly to ground outside the block, the net inside the block changes from "Click to plot V(n030)" to "This is ground." and the RTN hierarchical label changes from "Click to plot V(n030)" to "node "RTN" (0)."
All results were identical regardless of the "Input", "Output" or "Bi-Direct" selection of the RTN hierarchical label.
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When I ground the RTN label outside the block and move the resistor inside the block, everything works as it should.
The RTN label says "node "RTN" (0).", the resistor is grounded on both ends and its current cannot be plotted because it has been removed from the netlist.
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My observations:
1. If routing ground out of a hierarchical schematic, be absolutely sure to remove all of the triangular (label 0) ground symbols from the interior of that hierarchical block and physically connect any nets that may have been disconnected by those ground symbol removals.
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2. I have no evidence about the use of a hierarchical connector and conductors to route (plumb) the node 0 ground out of a hierarchical cell type sub-circuit because I have not had the need to experiment with such.
I would not be surprised to find that all nodes "0" within a sub-circuit would need to be renamed to something like "00" to ensure that LTspice does connect all those nodes together but does not sumarilly connect that net to ground.
Or maybe not, maybe LTspice treats node 0 within a sub-circuit cell differently then it treats the triangular (label 0) ground symbol within a sub-circuit block.
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If anyone has proved or disproved the assertions in number observation 2 above, please opine.
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All for now
eewiz