ABB ACS355 User Manual

402 Appendix: Safe torque off (STO)
 STO function activation and indication delays
STO activation delay is below 1 ms. STO indication delay (time from the de-
energization of any STO input to the updating of the status bit) is 200 ms.
Note: If any STO channel is toggled very fast, it is possible that the drive trips to
overcurrent or short circuit.
Installation
Connect the cables as shown in the diagram below.
STO input channels can be also supplied with an external power supply. The required
supply current is maximum 15 mA for each STO channel, and the voltage
requirement is 24 V DC +/-10%. The negative terminal of the power supply must be
connected to the analog ground (AGND) of the drive.
STO can also be daisy-chained from drive to drive, so that several drives are behind
one safety switch. If STO outputs (OUT1 and OUT2) are used to supply the STO
circuit, maximum five drives can be supplied. The number of drives depends on the
2414
2313 Y1
A2
Y2
A1
31
32
Safety relay
Safe PLC
OUT
GND
X1C: OUT1
X1C:3 IN1
X1C: OUT2
X1C:4 IN2
ACS355
2414
2313 Y1
A2
Y2
A1
31
32
Safety relay
Safe PLC
OUT
GND
X1C:1 OUT1
X1C:3 IN1
X1C:2 OUT2
X1C:4 IN2
ACS355
AGND
+24 V DC external
power supply
-
+

ABB ACS355 Specifications

General

Input Voltage	200 V to 240 V AC, 380 V to 480 V AC
Frequency	47 Hz to 63 Hz
Control Method	Scalar control
Protection Features	Overcurrent, Overvoltage, Undervoltage, Overtemperature, Short circuit
Communication Interfaces	Modbus RTU, CANopen
Enclosure Rating	IP20
Operating Temperature	-10°C to +50°C (14°F to 122°F)
Storage Temperature	-40°C to +70°C (-40 to +158 °F)
Humidity	95% RH (non-condensing)
Altitude	Up to 1000 m (3280 ft) without derating