Re: Remote RRamp-like Indicators
The complexity of the voltage waveform is the same for the current waveform. Both are bipolar pulses. A waveform that the most common DVM meters are not designed to read correctly. The bridge rectifier removes the bi-polar nature of the rectangular waveforms to a unipolar output. Given the waveform is a rectangular, the end result is that the rectifier converts the rectangular AC to 99% DC which any meter can measure accurately.
As Don said, there is calibration issue when reading voltage. You ave to account for the two diode voltage drops.
For current, the bridge rectifier does not introduce an error term but does reduce the final track voltage by two diode voltage drops. If a locomotive crosses a booster district where the track current is NOT monitored to one that is monitored, you can see the engine speed change. However, higher end DCC decoder with BEMF motor drive will minimize/compensate for that effect.
Taking a step back, I am always wondering why people think is it important to monitor the booster voltage and current. If you think it will give you a heads up on booster overload, that is not what actually happens. Most overload problem are not related to train running issue. They are recovery from a short circuit while dealing with high inrush current issues.
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