Allen-Bradley micrologix 1500, Руководство пользователя

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Publication 1764-UM001A-US-P
2-8 Installing Your Controller
Using Emergency-Stop Switches
When using emergency-stop switches, adhere to the following points:
•
Do not program emergency-stop switches in the controller program. Any
emergency-stop switch should turn off all machine power by turning off the
master control relay.
•
Observe all applicable local codes concerning the placement and labeling of
emergency-stop switches.
•
Install emergency-stop switches and the master control relay in your system.
Make certain that relay contacts have a sufficient rating for your application.
Emergency-stop switches must be easy to reach.
•
In the following illustration, input and output circuits are shown with MCR
protection. However, in most applications, only output circuits require MCR
protection.
The following illustrations show the Master Control Relay wired in a grounded
system.
NOTE
In most applications input circuits do not require MCR
protection; however, if you need to remove power from all field
devices, you must include MCR contacts in series with input
power wiring.