6-25
Safe Torque Off
AC30V series Variable Speed Drive
SS1 IMPLEMENTATION USING SAFETY CONTROL UNIT
This Safe Stop 1 (SS1) implementation causes the drive to come to rest in a controlled manner, and STO is actioned after a time delay determined by
the safety delay relay. This conforms to SS1 defined in EN61800-5-2:2007 para 4.2.2.3 c). The example shows wiring and terminal numbering for a
Siemens 3TK2827, but similar products are available from other vendors. Use of this Siemens part does not imply it is suitable for the user’s application.
The user must select and assess appropriate equipment.
Note:
On power-up, the Safety Control Unit outputs are OPEN; thus STO is requested of the AC30V. This responds by energising KA1 if both channels are
active and healthy. KA1 is used as a self-check for the reset cycle of the Safety Control Unit. If a reset cannot be achieved due to KA1 being de-
energised, a fault may be present and must be resolved by the user before relying on the STO function. See Fault Operation on page 6-14.
DRIVE
START
DRIVE STOP
AC30V STO
RESET
KA1
SAFETY
DEMAND
KA1
POWER SUPPLY
SAFETY CONTROL UNIT
THIS WIRING MUST BE WITHIN THE CONTROL CUBICLE.
24VDC
A1 Y10 Y11 Y12 Y21 Y22 13
47
57
A2
PE Y33
Y34 14
48
58
X13/02 X12/01
X10/01 X10/03 X10/06
X12/05
X10/02 X10/04 X10/05
X12/06
