FA236064
26 July 2022
Issue:PTC alarm installation
Product Line:Altivar 61, Altivar 71
Environment:All models, all serial numbers
Cause:Using PTC probes for motor overload protection, requesting warning indication rather than faulting the VFD
Resolution:PTC warning can be indicated via a relay output assigned to an Alarm Group.
Example for SW2 switch set to PTC, PTC connected to LI6, R2 indication, Alarm Group 1
1.8 Fault Management
PTC Management - activates the PTC monitoring
LI6 = PTC Probe [PTCL] = Always
Motor Thermal Prot - Inactivates the VFD internal I2T overload protection
Overload Fault Mgt [OLL] = Ignore
1.5 Inputs/Outputs CFG
R2 Configuration - assign relay R2
R2 Assignment [R2] = Alarm Grp1
Alarm Grp1 Definition - activate PTC alarm for the warning group
LI6 = PTC Alarm [PLA] = ON
Important note: When Overload Fault Mgt [OLL] = Ignore, the motor thermal protection by calculating the I2t is inactive. The drive will not provide motor overload protection based on motor current. Both functions can work at the same time by keeping Overload Fault Mgt [OLL] = Freewheel
