Danaher Motion
05/2008
Detailed Wiring Information
S200-CNS Product Manual
45
10 DETAILED WIRING INFORMATION
Connector pin-out detail is provided in the prior section of this manual. This section deals with the
details of the internal operation of the drive connections. This information is provided to allow the
system designer insight sufficient to create a robust system wiring plan.
10.1 C
ABLES
10.1.1 Long
Cables
The DC resistance of long motor power cables steals some of the available voltage when motor
current is high. The principal effect of this is some reduction in peak motor power so acceleration
and deceleration times can be longer. The cable resistance has no significant effect on lower speed
torque or top speed. For most applications, the loss of performance is small with cables up to the
maximum cable length specification. Do not operate a DC input S200 with long cables at the lower
end of the bus voltage range because too much of the available voltage is lost by the cable
resistance. For AC input S200s, the DC resistance of the motor power cable is rarely an issue
because the voltage drop across the resistance is usually a small fraction of the available nominal
bus voltage.
For DC S200 applications with long cables and demanding dynamics, the 14 AWG cable is
preferred over the 18 AWG cable. Cable voltage drop vs cable length is shown in the table below.
Cable Voltage Drop vs Length
V
LOSS
in cable as
a percent of 75 V bus
Cable
Length
(meter)
2 x Rphase
(ohm)
V line-line peak
at 0.866 x 18 A
RMS
18 AWG cable
18 cable
14 cable
3
0.126
2.77
3.7 %
1.5 %
10
0.413
9.09
12.1 %
4.8 %
25
1.03
22.7
30.3 %
12.0 %
50
(50 m not recommended with 6/18 A
RMS
) N/A
24.0
%
10.1.2 Custom Composite Cables
A composite cable has both feedback and power wires in one cable. One of the critical requirements
for a composite cable is to provide a high degree of isolation between the power and feedback
wires. For 240 VAC-connected drives, the power wires can have up to 400 V
peak-peak
fast switching
PWM waveforms that can couple to the feedback wiring, causing communication errors between the
Drive and the Smart Feedback Device (SFD).
Danaher Motion has developed and sells a composite cable that has very good isolation between
the power and feedback sections. It is strongly recommended that this raw cable be used for custom
composite cable designs. Contact your Danaher Motion sales representative for additional
information. If this cable does not meet your specifications, the following are some guidelines for
custom composite cable development.
Due to the complexity of modeling and understanding
cable coupling, a new composite cable needs to be prototyped and tested to have confidence
that it will be reliable.
Composite cable should have double concentric feedback shields – one shield within
another.
The raw composite cable that has been tested and is known to work well with the S200 has the
following structure:
double, concentric shields
around the feedback wires plus an outer shield
around the whole cable (see diagram below). This type of raw cable is strongly recommended.
Testing shows double, concentric, shielding is ten times better than single shielding at reducing
coupling from the power wires to the feedback data wires.