Mitsubishi A1SJH(S8) User Manual page 4

[DESIGN PRECAUTIONS]
If load current more than the rating or overcurrent due to a short circuit in the load has flowed in the
output module for a long time, it may cause a fire and smoke. Provide an external safety device such
as a fuse.
Design a circuit so that the external power will be supplied after power-up of the programmable
controller.
Activating the external power supply prior to the programmable controller may result in an accident
due to incorrect output or malfunction.
For the operation status of each station at a communication error in data link, refer to the respective
data link manual.
The communication error may result in an accident due to incorrect output or malfunction.
When controlling a running programmable controller (data modification) by connecting a peripheral
device to the CPU module or a PC to a special function module, create an interlock circuit on
sequence programs so that the whole system functions safely all the time.
Also, before performing any other controls (e.g. program modification, operating status change
(status control)), read the manual carefully and ensure the safety.
In these controls, especially the one from an external device to a programmable controller in a
remote location, some programmable controller side problem may not be resolved immediately due
to failure of data communications.
To prevent this, create an interlock circuit on sequence programs and establish corrective
procedures for communication failure between the external device and the programmable controller
CPU.
When setting up the system, do not allow any empty slot on the base unit.
If any slot is left empty, be sure to use a blank cover (A1SG60) or a dummy module (A1SG62) for it.
When using the extension base unit, A1S52B(S1), A1S55B(S1) or A1S58B(S1), attach the included
dustproof cover to the module in slot 0.
Otherwise, internal parts of the module may be flied in the short circuit test or when an overcurrent or
overvoltage is accidentally applied to the external I/O section.
[DESIGN PRECAUTIONS]
Do not install the control lines or communication cables together with the main circuit or power lines,
or bring them close to each other.
Keep a distance of 100mm (3.94inch) or more between them.
Failure to do so may cause malfunctions due to noise.
When an output module is used to control the lamp load, heater, solenoid valve, etc., a large current
(ten times larger than the normal one) may flow at the time that the output status changes from OFF
to ON. Take some preventive measures such as replacing the output module with the one of a
suitable current rating.
DANGER
CAUTION
A - 2