Copley Controls Xenus R10 Manual page 88

Accelnet R22
PC BOARD DESIGN
Printed circuit board layouts for Accelnet
R22 drives should follow some simple
rules:
1. Install a low-ESR electrolytic capacitor not
more than 12 inches from the drive. PWM
drives produce ripple currents in their DC
supply conductors. Accelnet R22 drives do
not use internal electrolytic capacitors as
these can be easily supplied by the printed
circuit board. In order to provide a good,
low-impedance path for these currents a
low-ESR capacitor should be mounted as
close to the drive as possible. 330 µF is
a minimum value, with a voltage rating
appropriate to the drive model and power
supply.
2. Connect J1 signals (U,V,W outputs,
+HV, and +HV Common) in pin-groups
for current-sharing. The signals on J1 are
all high-current types (with the exception
of the +24 Vdc Aux HV supply). To carry
DIMENSIONS
0.282
[7.2]
0.980
[24.9]
Notes
1. Dimensions shown in inches [mm].
Copley Controls, 20 Dan Road, Canton, MA 02021, USA
Tech Support: E-mail: sales@copleycontrols.com, Internet: http://www.copleycontrols.com
these high currents (up to 20 Adc peak)
the pins of J1 must be used in multiples
to divide the current and keep the current
carrying capacity of the connectors within
specification. The diagram on page 8 shows
the pin groups that must be inter-connected
to act as a single connection point for pc
board traces.
3. Follow IPC-2221 rules for conductor
thickness and minimum trace width of
J1 signals. The width and plating should
depend on the model of drive used, the
maximum voltage, and maximum current
expected to be used for that model. Power
supply traces (+HV, +HV Common) should
be routed close to each other to minimize
the area of the loop enclosed by the drive
DC power. Noise emission or effects on
nearby circuitry are proportional to the
area of this loop, so minimizing it is good
layout practice.
Motor signals (U,V,W) should also be routed
close together. All the motor currents sum
3.48
[88.4]
4.05
[102.7]
0.025 [0.6] SQ.
RUGGEDIZED DIGITAL
SERVO DRIVE FOR
BRUSHLESS/BRUSH MOTORS
to zero, and while the instantaneous value
in a given phase will change, the sum of
currents will be zero. So, keeping these
traces as closely placed as possible will
again minimize noise radiation due to motor
phase currents.
Accelnet R22 circuit grounds are electrically
common, and connect internally. However,
the J1 signals carry high currents while the
grounds on J2 (signal ground) carry low
currents. So, J2 signals should be routed
away from, and never parallel to the signals
on J1. Encoder signal pairs (A, /A, B, /B,
and X, /X) should be routed close together
for good transmission-line effect to reduce
reflections and noise.
The drive heatplate is electrically isolated
from all drive circuits. For best noise-
immunity it is recommended to connect the
standoffs to frame ground and to use metal
mounting screws to maintain continuity
between heatplate and standoffs.
2X Ø.169 [Ø4.29] HOLE
FOR NO. 6-32 [M3.5] SCREW
1.31
[33.3]
2.62
[66.5]
0.24 +.020
-.020
+0.5
6.1
-0.5
Tel: 781-828-8090
R22
RoHS
2.79
[70.9]
0.22 +.020
-.020
+0.5
5.6
-0.5
Fax: 781-828-6547
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