Rockwell Automation SA3100 Power Module Interface (PMI) Regulator - Manual (Page 37)

Resolver & Drive I/O Board 3-3
The Resolver & Drive I/O board contains a tracking ratiometric resolver-to-digital (R/D)
converter that outputs a 12- or 14-bit digital number indicating the absolute electrical
position of the resolver shaft. The resolution of the R/D converter is selected during
parameter entry. A two-bit revolution counter extends operation over four electrical
revolutions. The counter is reset whenever power is turned on to the system or a
system reset command is asserted by the PMI processor. When 12-bit mode is
selected, the resolver data format will be as shown in figure 3.3. Figure 3.4 shows the
resolver data format when 14-bit mode is selected.
The Resolver & Drive I/O board produces a nominal 26 volt rms 2381 Hertz sine wave
reference output signal which is capable of driving a 500 ohm load. The stator signals
(sine and cosine) are input through a matched isolation transformer pair. The
transformers are matched for gain and phase shift. The ratio of the sine and cosine
amplitudes is then converted to an angular position. Position data is sent to the UDC
module by the PMI processor before every scan of the UDC task. The UDC task
calculates speed using this position data.
Figure 3.2 – Resolver Feedback Connector Pinout
Figure 3.3 – Resolver Data Format (12-Bit Mode)
Figure 3.4 – Resolver Data Format (14-Bit Mode)
Reference Out (+)
Reference Out (-)
Sine Input (+)
Cosine Input (+)
External Strobe Input (+)
External Strobe Input (-)
Not Used
Not Used
Analog Input (+)
C
F
K
N
R
A
B
D
E
H
J
L
M
P
Sine Input (-)
Cosine Input (-)
Key Pin
Analog Input (-)
Analog Input Shield
1
1
1
1
1
1
1
1
1. These signals are not used on the Drive I/O only (no feedback) board.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
bits
revolution counter
resolver data 0 0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
bits
revolution counter
resolver data