4
these precautions conform to the guidelines for installation of Controllers as
recommended in the NEMA ICS 3-304 Control Standards.
Programming
Considerations
To conform with ICS Safety Recommendations, checks should be placed
in the controller to ensure that all writable registers that control critical
parts of plant or machinery have limit checks built into the program, with
an out-of-limit safe shut down procedure to ensure safety of personnel.
ICS 3-304.81 Safety Recommendations:
Consideration should be given to the use of an emergency stop function, which is independent of the programmable controller.
Where the operator is exposed to the machinery, such as in loading or unloading a machine tool, or where the machine
cycles automatically, consideration should be given to the use of an electromechanical override or other redundant means,
independent of the programmable controller, for starting and interrupting the cycle.
If provision is required for changing programs while the equipment is in operation, consideration should be given to the use
of locks or other means of assuring that only authorized personnel can make such changes.
These recommendations are intended as safeguards against the failure of critical components and the effects of such failures
or the inadvertent errors that might be introduced if programs are changed while the equipment is in operation. *
The ICS 3-304.81 Safety Recommendations are reproduced by permission of the National Electrical
Manufacturers Association from NEMA ICS 3-304
2.3 Communications Connections
The ports as you look at the back of the case, are the ports for connecting to a PLC or some external
device (Controller Connectors).
2.3.1 Connector COM1 [RS232], COM2 [RS232]
Cable
Requirements
Caution
Different cables are required for various devices. Restrict cable length to less than 500’
(150m) for RS485/422 devices and 50’ (15m) for RS232 devices to avoid
communications problems.
The COM light on the front of the MT-600/8000 will turn on with each Ethernet
communication. Shielded cable must be used for long lengths or cables run in an
electrically noisy environment.
Do not run cables next to AC power lines or near sources of electrical noise. Be sure
that the cable ends have been inserted all of the way into mating connectors and are
secure
Pin assignment of the 9 Pin, Male, SUB-D, COM1 [RS-232] and COM2 [RS-232] Port.
Pin Designations
COM1 [RS-232]
COM2 [RS-232]
Pin# Symbol
COM1 [RS232]
COM2 [RS232]
1
Not used
2
RxD
Received Data
3
TxD
Transmitted Data
4
TxD
Transmitted Data
5
GND
Signal Ground
6
RxD
Received Data
7
RTS
Ready to send output
8
CTS
Clear to send input
9
Not used
2.3.2 Connector COM1[RS485] , COM3[RS485] and COM3[RS232]
The 9 Pin, Female, SUB-D, COM1 [RS-485], COM3 [RS-485] and COM3 [RS-232] Port on the back
of the unit is the RS-232 and RS485/422 communications port for connecting to a controller.
