Fluke PM3370B user manual Definitions, Formula’s, Sn = Yz + Yn * Yr * Yu, Sensitivity, Offset

THE CPL PROTOCOL 6 - 39

Definitions

A waveform can be described as a set of two one dimensional arrays: S[1...N] and T[1...N]. The index n corresponds with the number of the samples and is an integer value in the range 1...N. The waveform of a sampled signal describes for a range of sample moments (T[1]...T[N]; usually expressed in seconds) the value of the signal at these moments (S[1]...S[N]; usually expressed in volts).

A waveform is sometimes expressed in other units. An FFT waveform for example gives for a range; of frequencies (T[1]...T[N]; expressed in Hz) the signal amplitude of these frequency components (S[1]...S[N]; expressed in dB). Another example is the possibility to multiply an input voltage with a floating point value of another dimension.

Formula’s
S[n]	S[n] is the value of sample n, expressed in Y-units.
	Y-units are usually expressed in volts.
	S[n] = (Yz + (Y[n] * Yr)) * Yu
Sensitivity	Usually the sensitivity is expressed in volt/div. In the oscilloscope,
	the range of the Y[n] values (Yrng) always equals 2^16 = 65535,
	which corresponds with 10.24 divisions on the screen. This gives a
	maximum vertical resolution of 6400 ’levels’ per division.
	Sensitivity is expressed in Y-units/division.
	Sensitivity = 6400 * Yr * Yu/div
Offset	Offset is the vertical screen position of the signal ground level,
	indicated by "1-" (excluding Y-pos shift). The offset can be adjusted
	with the front panel Y POS controls. For calculated traces the offset
	can be adjusted with the delta-controls in the MATHematics menu.
	Offset is expressed in Y-units (volts).
	Offset = -Yz * Yu
	Note: Traces can also be positioned with the Y-pos control in the
	RECALL menu, but this does not affect the offset. The
	reason is that Y-pos is a pure display function, which
	therefore does not affect the signal sampling, nor the
	calculation of a trace using a mathematics function.
T[n]	T[n] is the sample moment, expressed in X-units.
	X-units are usually expressed in seconds.
	T[n] = (Xz + (n-1) * Xr) + (dT-corr * Xr)) * Xu