GE Industrial Solutions EntelliGuard TU Trip Units - Manual (Page 19)

DEH-4567B EntelliGuard TU Trip Units: UL/ANSI Models
Protection
©2012 General Electric All Rights Reserved 9
Table 2-2: Nominal Clearing Times for Fuse Shaped Long Time Bands
X = 1.5 1.5 6 6 7.2 7.2 10 10
Commit Clear Commit Clear Commit Clear Commit Clear
Min F 0.67 1.54 0.025 0.085 0.025 0.085 0.025 0.085
F-2 2.0 4.40 0.025 0.085 0.025 0.085 0.025 0.085
F-3 3.6 7.98 0.025 0.085 0.025 0.085 0.025 0.085
F-4 5.6 12.5 0.025 0.085 0.025 0.085 0.025 0.085
F-5 8.1 18.0 0.032 0.100 0.025 0.085 0.025 0.085
F-6 11.2 25.0 0.044 0.13 0.025 0.085 0.025 0.085
F-7 15.1 33.8 0.059 0.16 0.028 0.094 0.025 0.085
F-8 20.0 44.7 0.078 0.20 0.038 0.114 0.025 0.085
F-9 26.1 58.4 0.102 0.26 0.049 0.14 0.025 0.085
F-10 33.8 75.4 0.13 0.32 0.064 0.17 0.025 0.085
F-11 43.3 96.8 0.17 0.41 0.082 0.21 0.025 0.085
F-12 55.3 123 0.22 0.51 0.104 0.26 0.028 0.092
F-13 70.2 157 0.27 0.64 0.13 0.33 0.036 0.109
F-14 88.9 198 0.35 0.81 0.17 0.40 0.045 0.13
F-15 112 251 0.44 1.01 0.21 0.50 0.057 0.16
F-16 141 316 0.55 1.26 0.27 0.62 0.072 0.19
F-17 178 397 0.69 1.58 0.34 0.78 0.090 0.23
F-18 224 499 0.87 1.98 0.42 0.97 0.113 0.28
Max-F 280 626 1.10 2.48 0.53 1.21 0.142 0.35
• Algorithm will not commit below 1.5 cycles, clearing time will not be less than 0.088 seconds.
• Actual Long Time pickup is 112% of nominal pickup.
SHORT TIME PROTECTION
Short Time Pickup
The Short Time Pickup function establishes the current at
which short time trip is activated. Short Time Pickup is with
a multiple of the Long Time Pickup and the choices of
pickup settings are from 1.5 to 12.0 times the Long Time
setting, xLT, in steps of 0.5 xLT.
The maximum pickup depends on breaker type and frame
as shown in Table 2-3, below:
The Short Time Pickup value tolerance band is
approximately -9% to +11% of the set point based on a
10% current sensing accuracy with the pickup calculated
with 1/ (1+Tolerance). The time current curve of short time
pickup is shown in Figure 2-3.
Figure 2-3: Short Time Pickup Time Current Curve