ActivationSOTF: This setting will select the signal to activate SOTF function;CB positionopen/CB position closed/CB close command.tSOTF: Time delay for operation of the SOTF function. The setting range is 0.000 - 60.000 s instep of 0.001 s. The default setting is 0.100 sStepForSOTF: If this parameter is set on the step 3 start signal will be used as current set level.If set off step 2 start signal will be used as current set level.t4U: Time interval when the SOTF function is active after breaker closing. The setting range is0.000 - 60.000 s in step of 0.001 s. The default setting is 1.000 s.ActUnderTime: Describes the mode to activate the sensitive undertime function. The functioncan be activated by Circuit breaker position (change) or Circuit breaker command.tUnderTime: Time delay for operation of the sensitive undertime function. The setting range is0.000 - 60.000 s in step of 0.001 s. The default setting is 0.300 s8.4.3.6 Line application example M15282-184 v7The Four step residual overcurrent protection EF4PTOC can be used in different ways. Below isdescribed one application possibility to be used in meshed and effectively earthed systems.The protection measures the residual current out on the protected line. The protectionfunction has a directional function where the polarizing voltage (zero-sequence voltage) is thepolarizing quantity.The polarizing voltage and current can be internally generated when a three-phase set ofvoltage transformers and current transformers are used.xx05000149.vsdIN>IEC05000149 V1 EN-USFigure 83: Connection of polarizing voltage from an open deltaThe different steps can be described as follows.Section 8 1MRK 505 363-UEN ACurrent protection150Application manual
