9 LOADING AND INSTALLATION
In order to increase the reliability of the system and exploit the maximum performance of its functions, this section describes the methods and precautions for the mounting and installation of the system.
9.1 General Safety Requirements
| ! DANGER | Install a safety circuit external to the PLC that keeps the entire |
| system safe even when there are problems with the external power |
| supply or the PLC module. Otherwise, trouble could result from |
| erroneous output or erroneous operation. |
(1)Outside the PLC, construct mechanical damage preventing interlock circuits such as emergency stop, protective circuits, positioning upper and lower limits switches and interlocking forward/reverse operations.
(2)When the PLC detects the following problems, it will stop calculation and turn off all output in the case of (a).
In the case of (b), it will stop calculation and hold or turn off all output according to the parameter setting.
Note that the A1S series module will turn off the output in either of cases (a) and (b).
All outputs of AnS Series Module will be switched off in the following cases:
(a)The power supply module has over current protection equipment and over voltage protection equipment.
(b)The PLC CPUs
dog timer error, detect problems.
In addition, all output will be turned on when there are problems that the PLC CPU cannot detect, such as in the I/O controller.
(3)Output could be left on or off when there is trouble in the outputs module relay or transistor. So build an external monitoring circuit that will monitor any single outputs that could cause serious trouble.
| When overcurrent which exceeds the rating or caused by short- |
| circuited load flows in the output module for a long time, it may |
| cause smoke or fire. To prevent this, configure an external safety |
| circuit, such as fuse. |
| Build a circuit that turns on the external power supply when the PLC |
| main module power is turned on. If the external power supply is |
| |
9 | turned on first, it could result in erroneous output or erroneous |
operation. | |
| When there are communication problems with the data link, refer to |
| the corresponding data link manual for the operating status of each |
| station. Not doing so could result in erroneous output or erroneous |
| operation.operating status of each station. Not doing so could result |
| in erroneous output or erroneous operation. |
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