Schweitzer Engineering SEL-351P - Accuracy; Pickup and Reset Time Curves; Settings Ranges

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Date Code 990430 Overcurrent, Voltage, Synchronism Check, and Frequency Elements 3-11

SEL-351P Manual Técnico

Figure SECTION 3: .9: Levels 5 through 6 Neutral Ground Instantaneous

Overcurrent Elements

Settings Ranges

Setting range for pickup settings 50N1P through 50N6P:

0.005 - 1.500 A secondary (0.05 A nominal channel IN current input)

Setting range for definite-time settings 67N1D through 67N4D:

0.00 - 16000.00 cycles, in 0.25-cycle steps

Setting range for definite-time setting 67N2SD (used in DCB logic):

0.00 - 60.00 cycles, in 0.25-cycle steps

Note: Because channel IN is rated 0.05 A nominal, there is an additional 2-cycle time delay on

all the neutral ground instantaneous (50N1 - 50N6, 67N1 - 67N6) and definite-time

(67N1T - 67N4T) elements. Any time delay provided by the definite-time settings

(67N1D - 67N4D) is in addition

to this 2-cycle time delay.

Accuracy

Pickup: ±1 mA secondary and ±5% of setting (0.05 A nominal channel IN current input)

Timer: ±0.25 cycles and ±0.1% of setting

Transient Overreach: ±5% of setting

Pickup and Reset Time Curves

See

Figure SECTION 3: .5 and Figure SECTION 3: .6.