METREL MI 3399, Инструкция с упражнениями

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Power and Voltage Quality Trainer AD 2
– MI 3399
131
100%
10%
IEC
EN50160
1%
max 1%
max.
3 min
max.
1 min
max 10%
short
interruption
long
interruption
min 3 min
min 1 min
Figure 2-3: nterruption threshold and duration definitions
Impact on customers’ equipment
In an industrial environment, interruptions can cause disruption in production by
increasing the number of rejects or material wastage. In some areas, interruptions can
increase the risk of equipment damage or even injury. Information technology is
affected in two ways. First, current data can be lost and the system can be corrupted.
Second, after interruption is over, the re-boot process, especially on a large and
complex system, can last for several hours. Because of these reasons, critical
computer systems and telecommunication equipment are supplied with UPS power.
2.6 Power measurement
Active Power (P)
Active power is the power generated if a voltage is placed over a purely resistive load
and current is allowed to flow. Active power is usually measured in watts (W) or
kilowatts (kW).
Reactive Power (Q)
Reactive power is the power that is generated by reactive components (e.g. inductors,
capacitors) to create a magnetic field. This is usually measured in Volt-Ampers reactive
(VAr).
Apparent Power (S)
Apparent power is the perceived power from a load that has both resistive and reactive
components. Apparent power is the vector sum of both active and reactive
power and is usually measured in Volt-Amperes (VA).
Power Factor
Power factor is a measure of a power system’s efficiency and is the ratio of real power
to apparent power.