Siemens 7SJ85 - Application and Setting Notes

The vector jump Δφ is stored in an RS flip-flop. Trippings can be delayed by the associated time delay.
Blocking the Stage
In the event of blocking, the picked up stage will be reset. The following blocking options are available for the
stage:
•
The parameter Mode is in the state off.
•
The binary input signal >Block stage is active.
•
The signal
Δφ out of meas. range is active.
Application and Setting Notes
Parameter: Operate & flt.rec. blocked
•
Default setting (_:19261:2) Operate & flt.rec. blocked = no
With the parameter Operate & flt.rec. blocked, you can block the operate indication, the fault
recording, and the fault log. If you want the stage to have a warning indication only, set the parameter
Operate & flt.rec. blocked to yes.
Parameter: Threshold Δφ
•
Default setting (_:19261:101) Threshold Δφ = 10°
With the parameter Threshold Δφ, you can set the pickup value of the Δφ stage.
The parameter value to be set for the vector jump depends on the supply and load conditions. Load changes
cause a jump of the voltage vector. The value to be set must be established in accordance with the particular
power system. An estimation can be done based on the system equivalent circuit in Figure 6-224. A network
calculation considering the relevant source and load situations will be more precise.
If the setting for the parameter Threshold Δφ is too sensitive, every time loads are connected or discon-
nected, the protection function performs a network decoupling. Therefore, If no other calculated value is
applicable to the setting of this parameter, Siemens recommends using the default setting.
Parameter: Operate delay
•
Default setting (_:19261:6) Operate delay = 0.00 s
With the parameter Operate delay, you can set the operate delay of the Δφ stage. For the tripping stage,
set the operate delay between 0.00 s and 60.00 s.
Siemens recommends the default setting.
The following requirements can necessitate a change of the parameter Operate delay with respect to the
default setting:
•
The operate indication should be transmitted with delay to a programmable logic.
•
There shall be enough time for an external blocking to take effect.
Parameter: T Reset
•
Default setting T Reset = 5.00 s
With the parameter T Reset, you can set the reset time for the
Pickup indication stored in the RS flip-flop.
When the timer T Reset expires, the protection function is reset automatically.
The reset time meets the following conditions:
•
The reset time depends on the decoupling requirements
•
The reset time must expire before the circuit breaker is reclosed
6.36.4.2
Protection and Automation Functions
6.36 Vector-Jump Protection
796 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017