Detailed Wiring Information
05/2008
Danaher Motion
54
S200-CNS Product Manual
10.13 R
EGEN
R
ESISTOR
W
IRING
Applicable Models: All AC Input units.
Many applications do not require the use of a regen resistor. Danaher Motion’s Motioneering
software can predict the need for a regen resistor. There is also an application note on the Danaher
Motion website (
) providing the equations to calculate the regenerative
levels. Nuisance over voltage tripping is the symptom indicating the need for a regen resistor.
Danaher Motion offers the ERH-26 regen resistor compatible for use meeting all the requirements of
the S200 Position Node product line.
Connection for an optional regeneration power resistor to absorb regenerated energy from the motor
is provided on each S200 Position Node. If the ERH-26 is not used then the user should choose a
wire-wound resistor with 1500 V
RMS
isolation between terminals and case. The regen resistor must
not have a lower ohm value than specified for the given drive. The power rating of the regen resistor
depends on the amount of regenerated energy that needs to be dissipated. In many applications
there is little need for an aggressive low-ohm value resistor. The chosen resistor must be self-
protecting against overheating failure. This can be done any number of ways including; thermal snap
action fuse protection, a series thermal overload heater relay, or with a resistor value that can limit
the maximum wattage to the rating of the resistor. Any protection using contacts would have the
switch wired into a safety circuit that shut down the system in the event of a resistor over
temperature to prevent a fire hazard.
Wiring to the regen resistor should be short and the leads should be twisted together. Although
never required, in systems with sensitive electronics it is not uncommon to shield these wires with a
braided cable with shields tied to earth at both ends. Thermal overload protection is wired into the
machine safety circuit such that it causes a machine shut-down upon sensing excessive regen
resistor temperatures.
10.14 S
TEP AND
D
IRECTION OR
E
LECTRONIC
G
EARING
W
IRING
The S200 Position Node has the ability to accept position commands from and external source in
the form of pulses. Typical systems use one of two devices for this command; incremental encoder
signals or step (pulse) and direction signals. The S200 PN electrical input circuits for these signals
uses differential line receivers and resistor biasing to allow use with differential line transmitters,
open collector, or TTL driver circuits. The circuit arrangement is shown in the following diagrams.
Due to this circuit design it is very important to tie the DC Commons of the two systems together.
Incremental encoder signals are typical of systems that are used as a gear-follower, some times
called master or line-shaft. Details of how these systems work can be found in the S200 Position
Node User’s Guide. The basics are that an encoder signal (A/B differential) is wired into the S200
PN’s J12 connector. These signals are translated into quadrature pulses that increment or
decrement the internal position loop command register, subject to acceleration and deceleration
limits. The S200 PN has no use for an encoder Z (marker or index) channel for these applications.
The source of these signals can be ether another controller with encoder outputs or a stand-alone
incremental encoder. A 5V supply is available at J12 as a power source for the stand-alone encoder.
Typical interconnect is presented below.