The term v(u1:hb,0) is in the
denominator of the function and I think it is zero at startup.
On 2025-02-21 13:07, Carlo wrote:
On Fri, Feb 21, 2025 at 04:31 AM, Andy I wrote:
But LTspice doesn't know this.? It sees the circuit
topology as a current source connected to another current
source, and it thinks the node where they join is "floating".?
So it generates the error message, but it continues to process
the netlist anyway, and everything works!
Looking at the complete circuit topology, U1:H2 node is the node
where the subckt G-source Ghot joins the external DC independent
current source (I1). In the overall circuit this U1:H2 node is
connected to GND (0). However U1:HB isn't the node where the two
current sources (internal and external) actually join.
?
Here the expanded netlist:
? ? --- Expanded Netlist ---
*
C:\Users\carlo\Documents\LTspice\Bravo_Ocean_ampli\12AU7heater.asc
r:u1:cool n001 u1:ha 6.2?
r:u1:load u1:ha u1:hb 1m
b:u1:¡ìesens u1:hd 0 v=v(u1:ha,u1:hb)*1000?
b:u1:¡ìepwr u1:he 0 v=v(n001,0)*v(u1:hd)/(pwr(6.3 ,2)/ 42)
r:u1:h1 u1:he u1:hf 91k
c:u1:h1 u1:hf 0 1.05e-05?
b:u1:¡ìeh2 u1:hg 0 v=v(u1:hf)?
r:u1:h2 u1:hg u1:hh 270k
c:u1:h2 u1:hh 0 1.05e-05?
b:u1:¡ìeh3 u1:hj 0 v=limit(v(u1:hh)-0.75,0,1e6)*4?
r:u1:h3 u1:hj u1:hk 91k
c:u1:h3 u1:hk 0 1.05e-05?
b:u1:¡ìghot u1:hb 0 i=(1/(v(u1:hg)+0.001))/(42 -
6.2)*v(u1:hb,0)
i1 0 n001 150m
.dc i1 120m 160m 1m
.end
?
ERROR: Node U1:HB is floating and connected to
current source G:U1:HOT
?
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
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