Disconnecting main power, Safety circuits, Disconnecting main power safety circuits – Rockwell Automation 1763 MicroLogix 1100 Programmable Controllers User Manual User Manual
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Publication 1763-UM001D-EN-P - March 2011
22 Installing Your Controller
Use only the following communication cables in Class I, Division 2 hazardous
locations.
Disconnecting Main Power
The main power disconnect switch should be located where operators and
maintenance personnel have quick and easy access to it. In addition to
disconnecting electrical power, all other sources of power (pneumatic and
hydraulic) should be de-energized before working on a machine or process
controlled by a controller.
Safety Circuits
Circuits installed on the machine for safety reasons, like overtravel limit
switches, stop push buttons, and interlocks, should always be hard-wired
directly to the master control relay. These devices must be wired in series so
that when any one device opens, the master control relay is de-energized,
thereby removing power to the machine. Never alter these circuits to defeat
their function. Serious injury or machine damage could result.
Communication Cables for Class I, Division 2 Hazardous Locations
1761-CBL-AM00 Series C or later
1761-CBL-AP00 Series C or later
1761-CBL-PM02 Series C or later
1761-CBL-HM02 Series C or later
2707-NC9 Series C or later
1763-NC01 Series A or later
WARNING
Explosion Hazard
Do not replace components, connect equipment, or
disconnect equipment unless power has been switched off.
WARNING
Explosion Hazard
Do not connect or disconnect connectors while circuit is
live.