Standards voltage regulation

Adler and Axelrod,58 in their two-channel spectrograph, have taken the ultimate step in this direction by measuring the two intensities simultaneously. We may take for granted that the proper use of-an internal standard can eliminate the effect of different variations in equipment in different cases. It follows that care may be relaxed in connection with variations thus eliminated for example, approximate voltage regulation suffices for an x-ray source used to excite both analytical lines when these are measured simultaneously. 

Power sources based on the zinc-mercuric oxide system are particularly suited to a wide range of applications, mainly concerned with miniature portable electronic equipment, where a relatively constant voltage is required throughout long discharge periods. In addition, such cells are used as voltage reference standards in regulated power supplies, potentiometers, chart... 

The control systems for the governors and automatic voltage regulators can be chosen from standard IEEE forms or can be built up separately to any degree of detail necessary. 

Figure 10.29 shows a standard configuration for a positive or negative, three-terminal, adjustable voltage regulator. 

With a frequency converter, stator voltage and frequency of the asynchronous motor can be varied infinitely. This transforms a standard motor into a variable speed drive system. An asynchronous motor equipped with a rotor position sensor, magnetization calculation, and the impression of the corresponding stator currents (vector regulation) has the properties of a servo drive. 

Usually, after a reaction is about 98% complete, a current of about 0.1 of the normal value is used. In the apparatus developed for coulometry of high accuracy, the voltage of the regulated power supply seldom changes by more than 0.001% in a day, the current is accurately measurable through the use of a standard resistor (known to better than 1 ppm) of high precision, and adjustment of the iR drop is made equal to that of a Weston cell. The time can be measured to an accuracy of 1 ppm or better. ... 

A 550 watt Conrad/Hanovla medium pressure A.C. mercury lamp surrounded by a 1 cm thick pyrex water jacket, for cooling and Infrared absorption, provided the Irradlance, while an electrical heater and fan system was used to adjust the sample temperature. The lamp was allowed to operate from Its standard power supply with no attempt at regulation of the Irradlance. Lamp voltage and current were the only parameters monitored to characterize Its performance. The exposure region was a perforated aluminum cylinder 34 cm In diameter and 23 cm high. 

---