cupoftea
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Hi,
This sounds totally nuts, but apparently there is such thing as a 0-10V signalling bus, where the things that are receiving the 0-10V
signal actually draw their bias (running) current from it. Why they don't just draw that bias current from their voltage source supply
I don't know.
Anyway, what this means is, that the transmitter of the 0-10V "signal" is often implemented by a linear regulator,
and so when eg the signal is down at 1V...then the linear-mode signal transistor dissipates (Vcc-1)/(bias current)
The bias current can be as high as 64mA, and the Vcc can actually be 20V, especially on joint DALI/0-10V comms lines.
This all means over a Watt being dissipated in the "signal" transistor.
So the question is, how common are these 0-10V bus's where the loads actually draw current from the 0-10V bus? (as opposed to just reading
it as a pure voltage signal)?
This sounds totally nuts, but apparently there is such thing as a 0-10V signalling bus, where the things that are receiving the 0-10V
signal actually draw their bias (running) current from it. Why they don't just draw that bias current from their voltage source supply
I don't know.
Anyway, what this means is, that the transmitter of the 0-10V "signal" is often implemented by a linear regulator,
and so when eg the signal is down at 1V...then the linear-mode signal transistor dissipates (Vcc-1)/(bias current)
The bias current can be as high as 64mA, and the Vcc can actually be 20V, especially on joint DALI/0-10V comms lines.
This all means over a Watt being dissipated in the "signal" transistor.
So the question is, how common are these 0-10V bus's where the loads actually draw current from the 0-10V bus? (as opposed to just reading
it as a pure voltage signal)?