Toshiba Programmable Logic Controller V200 - Manual (Page 18)

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0.6 System Integration Precautions
The following precautions are provided as general guidelines for using an V200 in an
industrial or process control system.
• The Toshiba PLC is a general-purpose product. It is a system component and is used in
conjunction with other items of industrial equipment such as PLCs, Loop Controllers,
Adjustable Speed Drives, etc.
• A detailed system analysis and job safety analysis should be performed by the
systems designer or systems integrator before including the V200 in any new or
existing system. Contact Toshiba for options availability and for application-specific
system integration information if required.
• The PLC may be used to control an adjustable speed drive connected to high voltage
sources and rotating machinery that is inherently dangerous if not operated safely.
Interlock all energy sources, hazardous locations, and guards in order to restrict the
exposure of personnel to hazards. The adjustable speed drive may start the motor
without warning. Signs at the equipment installation must be posted to this effect. A
familiarity with Auto-restart settings is a requirement when controlling adjustable speed
drives. Failure of external or ancillary components may cause intermittent system
operation, i.e., the system may start the motor without warning or may not stop on
command. Improperly designed or improperly installed system interlocks and
permissives may render a motor unable to start or stop on command
• Control through serial communications can fail or can also override local controls, which
can create an unsafe condition. System safety features should be employed and
designed into the integrated system in a manner such that system operation, even in the
event of system failure, will not cause harm or result in personnel injury or system
damage. Use of the built-in system protective features and interlocks of the equipment
being controlled is highly recommended (i.e., emergency-off, overload protection, etc.)
• Never use the PLC units to perform emergency stops. Separate switches outside the
V200, the PLC, and the ASD should be used for emergency stops.
• Changes or modifications to the PLC program should not be made without the approval
of the system designer or systems integrator. Minor changes or modifications could
cause the defeat of safety interlocks and permissives. Any changes or modifications
should be noted and included with the system documentation.