Applied Motion 1240i-485 - Manual (Page 9)

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Connecting to the Host Computer
•The 1240i-485 includes a multi-drop RS-485 communcation interface that must be
connected to the RS-485 port of a host computer. Up to 32 drives can be connected
to one host and individually commanded in real time. Each drive is “addressed” by a
special character, unique to each drive, included at the beginning of each command.
To assign an address character to each drive in your system, you’ll first need to con-
nect each drive individually to the host. A Windows PC and the SCL Setup Utility is
the easist way to do this.
The RS-485 standard allows both 2 wire and 4 wire configurations. The 1240i
supports the four wire type. Consider yourself lucky, as four wire RS-485 does not
require the host to disable its transmitter after each command is sent, and with four
wires you can send commands and receive data back at the same time.
If you plan to use a Windows PC as your host, then you’ll need to purchase an RS-232
to RS-485 adaptor. We’ve had excellent results with the model 117701 adaptor, sold
by Jameco (800-831-4242). If your RS232 port is like most, it has only 9 pins, so
you’ll need a “9 pin to 25 pin serial cable”. That’s also available from Jameco: model
31721.
A+
A–
B+ B–
8
lead
motor
8 Leads Series Connected 8 Leads Parallel Connected
A+
A–
B+
B–
8
lead
motor
Orange
Org/Wht
Blk/Wht
Black
Red Red/
Wht
Yel/
Wht
Yellow
Orange
Org/
Wht
Blk/Wht
Black
Red
Red/Wht
Yel/
Wht
Yel
low
Eight lead motors can also be connected in two ways: series and parallel. As
with six lead motors, series operation gives you more torque at low speeds and less
torque at high speeds. In series operation, the motor should be operated at 30%
less than the rated current to prevent overheating. The wiring diagrams for eight lead
motors are shown below.