Restart Prevention For Sto Application; Automatic Restart Of Sto Application; System Configuration Security; Service And Maintenance - Danfoss VLT AutomationDrive EZ FC 321 Operating Manual

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Operating Guide

4.5.1 Restart Prevention for STO Application

Application where parameter 5-19 Terminal 37 Safe Stop is set to default value [1] Safe Stop Alarm.
Procedure
1. Remove the 24 V DC voltage supply to terminal 37 using the interrupt device while the drive runs the motor (that is, mains
supply is not interrupted).
2.
Check that:
- a. The motor coasts.
b.
- The mechanical brake activates (if connected).
- c.
The LCP (if mounted) shows Alarm 68, Safe Stop.
3. Reapply 24 V DC to terminal 37.
4.
Ensure that the motor remains in the coasted state, and that the mechanical brake (if connected) remains activated.
5. Send a reset signal via bus, digital I/O, or [Reset] key.
6.
Ensure that the motor is operational again.
When all given steps are passed, the commissioning test is successfully completed.

4.5.2 Automatic Restart of STO Application

Applications where parameter 5-19 Terminal 37 Safe Stop is set to [3] Safe Stop Warning or combined STO.
Procedure
1.
Remove 24 V DC voltage supply to terminal 37 by the interrupt device while the drive runs the motor (that is, mains supply
is not interrupted).
2.
Check that:
- a. The motor coasts.
b.
- The mechanical brake activates (if connected).
- c.
The LCP (if mounted) shows Warning 68, Safe Stop.
3. Reapply 24 V DC to terminal 37.
4.
Ensure that the motor is operational again.
When all the given steps are passed, the commissioning test is successfully completed.
See the warning on the restart behavior in

4.6 System Configuration Security

• Security measures are the responsibility of the user.
• The drive parameters can be password-protected.

4.7 Service and Maintenance

It is required for PL d or SIL2 to conduct a functional test every 12 months to detect any failure or malfunction of the STO functional-
ity. For lower PL or SIL, it is a recommendation.

4.7.1 Performing Functional Tests

It is required to perform successful functional tests. If hardware faults are detected during a test, leading to situations where step 3–
5 and step 7 cannot be verified:
• Immediately initiate the STO.
• Replace the faulty unit and run a successful commissioning test before resuming normal operation.
• Operation is not allowed with a faulty unit.
• Repair is not allowed.
• If a failure is found in the periodic test, it must result in a safe state. The drive cannot guarantee a safe state so the test must be
conducted in a way that secures a safe state, for example, via a safety PLC.
Procedure
1. Remove 24 V DC voltage supply at terminal 37.
12 | Danfoss A/S © 2022.11
N O T I C E
2.5 Safety Precautions.
Commissioning
AQ355238304444en-US0301 / 130R0955