MKS Stabil-Ion 370 Series, Инструкция по эксплуатации, Страница: 32 / 122

2 Initial Setup Procedures
2-12
Series 370 Stabil-Ion Instruction Manual - 370119
2.1.5 RS-485 Computer Interface Setup
The RS-485 communications option for the Series 370 Stabil-Ion Gauge Controller permits data
output to, and gauge control by, a host computer using RS-485 digital communications.
Communications handshake is by a command-response mechanism.
A variety of baud rates and byte framing options are available. The RS-485 byte format is configured
to your system requirements using configuration switches located on the option board. These
switches are accessed by removing the controller top chassis cover.
The RS-485 factory defaults are:
■
9600 BAUD, 8 character bits, no parity, 1 stop bit, Address = 01
Internal switches are read upon power up. Changes in settings will take effect upon next power-up
cycle.
2.1.5.1 RS-485 Address
The address dial on the RS-485 module on the back of the controller and Switch S1determine the
controller’s RS-485 address. This address can be any hex code from 00 to FF.
The address dial on the RS-485 module on the back of the controller determines the value of the
least significant digit and the S1 switches determine the value of the most significant digit. The S1
switch positions are binary and the weight of each switch when OFF is given in Table 2-10.
To prevent data contentions, no two RS-485 nodes should be set with the same address. It is not
recommended that address 00 be used because some manufacturers use this address for
configuration.
2.1.5.2 Response Delay for the RS-485 Interface
Switch S2.1, Figure 2-15, enables a delay of the response from the module of 10 to 13 MS + 10 bit
times when OFF. When S2.1 is ON, the delay is greater than 700 microseconds. The factory default
setting is ON, with a delay greater than 700 microseconds.
Table 2-10 Switch Weight When OFF
Switch Weight
S1.1 10 Hex
S1.2 20 Hex
S1.3 40 Hex
S1.4 80 Hex
Figure 2-15 Back Panel and Top View of RS-485 Module