DOC-0017-03-EN: AC15 Series - Hardware Installation Manual     
60 (125)  DOC-0017-03-EN-B   04.04.2023  
 Test Protocol Specimen 
 
Machine: 
______________________ 
Name of Tester: 
______________________ 
Inverter: 
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Functionality: 
☐ 
Successfully tested (Test steps 1 – 18) 
☐
☐
Test: 
_____________________ 
Repeated Test: 
_____________________ 
Tester: 
_____________________ 
Tester: 
_____________________ 
 
 
 Regular Checks 
A regular check is intended only to demonstrate that the STO is functional. It will not always detect the loss 
of a single channel, so it is therefore important for the user and/or machinery builder to determine the 
frequency of the comprehensive checks based on their knowledge and application of the machine. 
A regular check is recommended once per week. 
Where a regular check coincides with the timing of a comprehensive check, the comprehensive check must 
take precedence. 
The following steps must be performed and recorded during a regular check: 
 
Step  Test Check or Activity  Expected Reaction & Effect 
1 
Firstly, ensure that no harm can come to 
personnel or equipment if the motor turns. 
None. 
2 
Apply +24Vdc to the inverter control board 
terminals STOA and STOB, and 0V to the 
STO 0V terminal. 
None. 
3 
Switch on power to the inverter. 
No error must be present in the drive 
system. 
4 
Try to start the inverter with a non-zero 
setpoint. This setpoint value will be referred 
to as SPT1 for brevity in these tests. Leave 
this set throughout all tests. 
Inverter must start and the motor must turn 
at SPT1. 
5 
With the inverter running and the motor 
turning at SPT1, disconnect terminal STOA 
and STOB within 1 second of one another. 
Leave both disconnected for approximately 
5 seconds. 
Motor must immediately coast to a rest. 
Inverter must report a STO trip immediately.