Unitek Peco 3-131-XX, Руководство пользователя

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Page 34 WELD SENTRY 2
SAMPLING RATE
One voltage and current measurement is "sampled" every 40 microseconds during the programmed
acquisition period. This corresponds to a sampling rate of 25,000 samples per second, or 25KHz. The
sample data is used as calculations for measurement units.
ACQUISITION TIME
The maximum allowed acquisition time is 500 milliseconds. The time during the weld when the Sentry is
actively collecting measurement data is called the acquisition period. The acquisition period is defined by a
"start" time and a “stop” time referenced from the trigger. A total of 3 separate acquisition periods can be
defined for a schedule, however, the total time cannot exceed 500ms.
MEASUREMENT TIME
The maximum allowed measurement time is 500 milliseconds. The time during the acquisition period for
which the Sentry calculates measurement results is called the measurement window. The Measurement
Window is defined by a "delay time" and a "measurement time" beginning at the start of an acquisition
period. The measurement window must be equal to or smaller than the acquisition period.
MONITORING RATE
The Monitoring Rate is defined as the number of individual welds that can be monitored over a period of
one second. The time required to monitor a weld includes the combined acquisition time, processing time
and transmission time. The shortest combination of these times will result in the fastest Monitoring Rate.
Transmitting data to a computer at a speed of 9600 Baud reduces the monitoring rate by approximately
50%. With no data output, the maximum Monitoring Rate for a half-cycle or single short weld pulse is 15
welds per second.
MEASUREMENT CALCULATIONS - Formulas used to calculate the Measurement Units are:
Peak Amps and Peak Volts are the maximum values which occur during the measurement window. Peak
Watts is the maximum value of Volts
●
Amps which occurs during the measurement window. Ohms @ peak
is the maximum value of Volts
÷
Amps which occurs at the same instant as Peak Watts.