Amperage draw

As a rule, the speed variation in a constant-speed machine is about 15 per cent. For an electric motor, the actual variation can be determined by obtaining the difference between the amperage drawn under full-load and no-load. This difference, taken as a percentage of full-load amperage draws, provides the actual percentage of speed-range variation that can be expected. 

Almost never take a person s word for the water recirculation rate. Check the number of pumps available and the number operational, read the pump plate, use pump curves, read the pump manual, measure using pitot tubes (measures the total pressure and hence indirectly the velocity), orifice plates, V-notch weirs, and distribution deck levels, or calculate based on amperage draw and the discharge pressure, to confirm the volume of water actually circulating in the system. 

During this period, additional data is collected, including data associated with motor amperage draw, pump curve performance, interface control, and operational baseline parameters, such as noise, vibration, and performance specifications are initiated. 

Continuous operation of the load-out conveyor is desired to minimize the number of hourly / daily starts and stops and to reduce the peak amperage draws in the imdergroimd power distribution system. However, the system is typically designed to handle approximately 30 starts per hour to accommodate this stop / start style operation in the event the mine operator chooses to operate the system in that manner. 

Figure 10.37. Amperage draw vs. concentration ofUHMW silicone. [Data from Lupton, K. E. Pape, P. G John, V. B., Intern. Conf Additives for Polyolefins, Houston, Feb. 23-25,1998, 93-106,1998.]...

The problem described above is called cavitation. A pump that is operating in a cavitation mode may also (but often does not) produce a sound similar to shaking a bucket full of nuts and bolts. A cavitating motor-driven pump always draws an erratically low-amperage flow. This is consistent with the erratically low flow rate. 

There are formulas to calculate gas production output under ideal conditions. These calculations are handy to make comparisons with your field and bench tests. For instance, to calculate the output of hydrogen and oxygen during an hour, first, measure the voltage at the electrolyzer terminals during operation. Then measure the amps as indicated earlier. Then, multiply the voltage times the amperage to get the power draw of the electrolyzer in watts. 

A motor running hot will draw more amperage than a cool motor. A refrigeration compressor motor that is tripping off at reduced refrigeration duty should be checked for proper operation of the motor s cooling fan. Sometimes, the motor s exhaust air vents may be partially blocked, leading to hot motor operation. 

Fias the size of the original pump impeller been increased A larger impeller can cause the pump s motor to draw more amperage. 

FLA (full-limit amps) This is the maximum amperage a motor should draw before it automatically trips off—rather like the 20-A circuit breaker at home. 

If reducing the load doesn t do the trick, you may have a more serious problem—a short circuit commonly occurs when exposed wires touch, either a hot wire to another hot, or to a neutral wire or a ground. A short circuit lets electricity bypass anything that offers resistance—an appliance or other electrical component—and allows the circuit to draw infinite amperage. This is bad— wires asked to carry an overly large load can melt through their coatings and start fires. That s the reason for a circuit breaker in the first... 

Just before peak power draw, or max. amperage. When the batch has come together. ... 

Heating system power consumption was tracked by monitoring the single-phase (band-heaters) and 3-phase (induction) current draws, while intermittently measuring the supply voltage and power factor (induction). The temperatures and amperages were measured at 1 second intervals with a Fluke data acquisition system. 

---