Sto State Monitor Output (Edm) - Hitachi SJ Series Safety Function Manual

Chapter 3
3.4.5
Holding function of STO state
(Not supported as Safety related function)
SJ-P1 does not support a function to hold STO state even
after releasing of STO inputs. Please consider it when
designing a system and, if needed, prepare an external
mechanism to avoid an unintentional restart of the system.
For more detailed information, please refer to Chapter 4.
3.4.6

STO state monitor output (EDM)

Please use EDM signal output when it is required to
monitor state of the STO inputs to SJ-P1 and state of
internal safety paths (failure detection state) by external
devices.
Please refer to Chapter 4 for the behavior and function
(signal matrix) of EDM signal.
EDM signal output is NOT a safety-related signal, but a
reference signal. This signal is not capable of being used to
activate another safety function.
Safety-Related information and consideration
3.4.7
Periodical functional test
A periodical functional test to check proper functioning of
the STO function must be performed at least once a year in
order to maintain the intended SIL / PL.
Please refer to Chapter 10 for the details of the functional
test.
3.4.8
Caution for using the STO function
The STO function does not cut the power supply to the
inverter and the peripheral circuits, and does not provide
any electrical isolation. Before maintenance, please ensure
to separate the system/machine from main power supply
lines and from the other devices which may supply any
voltage (e.g. permanent magnetic motor, device including
capacitors). Additionally, wait more than 10 minutes(*1) /
more than 15 minutes (*2) and check the charge lamp of
the inverter is disappeared, and then confirm that the
voltage between P and N terminal is lower than 45V before
performing maintenance.
*1) Type of P1-00044-L～P1-01240-L (P1-004L～P1-220L)
and P1-00041-H～00620-H (P1-007H～P1-220H)
*2) Type of P1-01530-L～P1-02950-L (P1-300L～P1-550L)
and P1-00770-H～P1-03160-H (P1-300H～P1-1320H)
The STO functionality is achieved only through the ST1
and ST2 connector of the inverter.
When permanent magnet motor or synchronous reluctance
motor is driven,
semiconductor failure, the inverter system can produce an
alignment torque which maximally rotates the motor shaft below
regardless of the activation of the STO function.
- 180/(p/2) degrees (with permanent magnet motors)
- 180/p degrees (with synchronous reluctance motors)
p denotes the number of pole.
3-2
in case of a multiple IGBT power