How It Works - Hitachi WJ200-001S Quick Reference Manual

Functional Safety
Introduction
The Gate Suppress function can be utilized to perform a safe stop according to the
EN60204-1, stop category 0 (Uncontrolled stop by power removal) (as STO function of
IEC/EN61800-5-2). It is designed to meet the requirements of the ISO13849-1 Cat.3 PLd,
IEC61508 SIL2 and IEC/EN61800-5-2 SIL2 only in a system in which EDM signal is
monitored by an "External Device Monitor".
Stop Category defined in EN60204-1
Category 0 : Uncontrolled stop by immediate (< 200 ms) shut-down of the power supply to
Category 1 : Controlled stop by interrupting the power supply to the actuator level if, for
Category 2 : Controlled stop. The power supply to the drive element is not interrupted.

How it works

Interrupting the current to GS1 or GS2, for
example removing the link between either GS1
or GS2 and PLC or both GS1/GS2 and PLC
disables the drive output, i.e. the power supply
to the motor is cut by stopping the switching of
the output transistors in a safe way. EDM output
is activated when GS1 and GS2 are given to the
drive.
Always use both inputs to disable the drive.
EDM output conducts when both GS1 and GS2
circuits are working properly. If for any reason
only one channel is opened, the drive output is
stopped but the EDM output is not activated. In
this case the Safe Disable input wiring must be
checked.
Activation
Turning on the safety switch automatically
assign the GS1 input and GS2 input
automatically.
To assign EDM (External Device Monitor) output,
the actuators. (as STO function of IEC/EN61800-5-2)
example, the hazardous movement has been brought to a standstill
(time-delayed shut-down of the power supply).
Additional measures to EN 1037 (protection from unexpected restart) are
necessary. (as SS2 function of IEC/EN61800-5-2)
(as SS1 function of IEC/EN61800-5-2)
Safety function
switch
OFF
96
EDM function
switch
OFF
ON
(normal)
ON
(EDM)