Using Sto Function; Introduction; Terms Related To Safety; Cautions - Mitsubishi Electric MELSERVO-J4 series Instruction Manual

13. USING STO FUNCTION

13. USING STO FUNCTION

13.1 Introduction

This section provides the cautions of the STO function.
13.1.1 Summary
This servo amplifier complies with the following safety standards.
ISO/EN ISO 13849-1 category 3 PL d
IEC 61508 SIL 2
IEC/EN 61800-5-2 SIL 2

13.1.2 Terms related to safety

The STO function shuts down energy to servo motors, thus removing torque. This function electronically cuts
off power supply in the servo amplifier.
The purpose of this function is as follows.
(1) Uncontrolled stop according to stop category 0 of IEC/EN 60204-1
(2) Preventing unexpected start-up

13.1.3 Cautions

The following basic safety notes must be read carefully and fully in order to prevent injury to persons or
damage to property.
Only qualified personnel are authorized to install, start-up, repair, or service the machines in which these
components are installed.
They must be familiar with all applicable local regulations and laws in which machines with these
components are installed, particularly the standards mentioned in this manual.
The staff responsible for this work must be given express permission from the company to perform start-up,
programming, configuration, and maintenance of the machine in accordance with the safety standards.
WARNING
Protective Measures
This servo amplifier satisfies the Safe Torque Off (STO) function described in IEC/EN 61800-5-2 by
preventing the energy supply from the servo amplifier to the servo motor. If an external force acts upon
the drive axis, additional safety measures, such as brakes or counterbalances must be used.
POINT
In the torque control mode, the forced stop deceleration function is not available.
Improper installation of the safety related components or systems may cause
improper operation in which safety is not assured, and may result in severe
injuries or even death.
13 - 1