Chapter 3 Safety-Related Information And Consideration; Contents In This Chapter; Chapter 4 Safety Function - Hitachi SJ Series Safety Function Manual

Chapter 3
Chapter 3 Safety-related
information and consideration

3.1 Contents in this chapter

This chapter describes safety-related information and
considerations.
3.2 Requirement of
Machinery Directive
In order to fulfill the requirements of the Machinery
Directive, all requirements in the applicable standards
must be satisfied and SJ-P1 inverters must be used in
accordance with the instructions provided in this Safety
function Guide and the User's Guide of the SJ-P1.
Before using the inverter, the risk assessment of whole
system must be conducted and appropriate measures must
be taken.
3.3 Intentional misuse
The SJ-P1 is not designed to protect against intentional
misuse/interference for STO function.
3.4 Safety consideration
3.4.1
Safety function
The SJ-P1 inverter supports the STO function which is
equivalent to STO (Safe Torque Off) function defined in
EN/IEC61800-5-2 as well as Category 0 Stop defined in
EN/IEC60204-1.
The SJ-P1 inverter shuts off power to a motor when STO
inputs are given.
Safety-Related information and consideration
3.4.2
Response time
The response time is defined as a time from input of Safety
request to actual activation of safety function.
In case of STO function, it is a time from input of STO signals
until power to a motor is shut off.
The response time of the STO function of the SJ-P1 is less
than 10ms.
A safety-related system must be designed in consideration
of the above mentioned response time so that this delay
time may not lead to any hazardous situation.
3.4.3
Self-Diagnosis of internal path
The SJ-P1 is equipped with the self-diagnosis function
which detects a fault in the internal safety paths.
When an internal fault has been detected, the safety paths
are maintained shut-off regardless of the states of the STO
inputs to the SJ-P1.
3.4.4
STO Input
The STO inputs of the SJ-P1 are redundant and the both
input signals must be input. The two STO inputs must be
appropriately separated from each other. If only one of the
inputs is used, the conformities to the applicable norms
become invalid.
The SJ-P1 inverter is not equipped with a diagnosis function
of input signal and line from an external device. A system
must be designed so that both of the STO inputs are always
given properly and simultaneously. As needed, please use
the EDM signal for failure detection of STO input lines to
configure a system which is able to detect a fault in STO
input lines.
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