Elmo SERVO AMPLIFIER DBP SERIES - Manual (Page 88)

87
DBP - Rev 6/93
Oscillator
Creates sinusoidal waveform signal to excite the primary of the Resolver.
Oscillator Frequency/Amplitude Selection (R228,R233)
The frequency (fr) and amplitude (Vr) needed to excite the Resolver are
taken from the Resolver data sheet.
Selecting the frequency:
R228 = 110/fr (Kohm)
0.1KHz < fr (KHz) < 20KHz
Selecting the amplitude:
Pay attention that the RMS amplitude does not exceed 7Vrms or that the peak-
to-peak (ptp) value is within the range of 2V < Vrptp < 20V. For Vr in
peak-to-peak value:
R233 = 6/(Vr - 2) (Kohm)
For Vr in RMS value:
R233 = 6/(2.82Vr - 2) (Kohm)
Reference Voltage level to R/D (R192)
In order to adjust the reference voltage input level to 2Vrms, select R192
as follows:
R192 = 50 x (Vrrms - 2) (Kohm)
For Vrrms <2V, install R192=100 ohm.