Development of a wavelet-based algorithm to detect and determine ...

4.3. FILES FOR DATA EXCHANGE 23
p= channel phase identification
cccccc= circuit/component being monitored
uu= channel units (kV, kA, etc.)
a= real number (see below )
b= real number. Channel conversion factor is ax+b
[i.e., a recorded value of x corresponds to (ax+b) in units uu
specified above]
skew= real number. Channel time skew (in µs) from start of sample period
min= an integer equal to the minimum value (lower limit of
sample range) for samples of this channel
max= an integer equal to the maximum value (upper limit of sample range)
for samples of this channel
m= (0 or 1) the normal state of this channel (applies to digital
channels only)
This "nn,id,p,cccccc,uu,a,b,skew,min,max" sequence is necessary to provide the
channel names, phase, units, and conversion factors for each of the channels in
the order in which they occur in the data. Phase, circuit component, and conver-
sion factors are not necessary for digital channels and thus are omitted.
In the above record format specification, the line seperated by dashs represent
analog channels and the last two lines represent digital channels.
The real value for the analog value is calculated as follows:
value = x · a + b
• Line frequency
The line frequency is listed on a seperate line in the file:
lf
where:
lf= line frequency in Hz (50 or 60)