CTI 2500-C100, Инструкция по установке и эксплуатации

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CTI 2500 Installation and Operation Guide V2.8 20
Operator Safety Switches
Power should be configured so that it can be manually removed from all output devices. You
must provide a method that is independent of the control system for disconnecting power from
the outputs when a machine is not operating or the operator must reach into the machine. A
non-electronic switch or directly wired relay must be used to disconnect the power.
Emergency Stop Switch
You must provide a method for disconnecting power from the outputs if an emergency situation
is encountered with the machine operation. Use a non-electronic switch or relay that is wired
external to the controller and that is easily accessible.
2.1.2 Electrical Interference
Electrical interference can adversely affect the operation of control equipment. The major
sources of electrical interference in an industrial environment are devices that use high voltages
and current, such as motors and welders. Electrical interference can be conducted directly
through wiring or inducted via electromagnetic coupling.
To ensure a reliable control system, you will need to determine the source of the electrical
interference and employ suitable techniques to eliminate it.
2.1.3 Grounding
It is very important that the all equipment is properly grounded. Lack of proper grounding may
cause intermittent or erratic operation or may cause the control system to fail. A properly
installed grounding system will provide a low-impedance path to earth ground, which will give all
PLC internal filtering devices a good ground return for reference. The earth ground of the
building site typically provides reliable grounding; however, if excessive ground current is
present, a separate grounding electrode should be installed.
A common practice is to provide a central ground bus bar as a single point of reference within
each enclosure, connecting all chassis and power supply components to the bus bar. The bus
bar is then connected to earth ground. When connecting to the bus bar, use 1 inch copper braid
or No. 8 AWG wire. To ensure good connections, scrape paint or other non-conductive coatings
away from mounting studs and from enclosure surfaces where mounting bolts and washers
make contact.
In addition to connecting the controller rack and power supply to earth ground, you must ensure
that the power supply, controller and all modules installed in the base are installed securely and
that the thumbscrews are tightened.