GE Multilin F650 User Manual

5-34 F650 Digital Bay Controller GE Multilin
5.4 PROTECTION ELEMENTS 5 SETPOINTS
5
5.4.2.4 ANSI CURVES
This family of curves complies with American Standard ANSI C37.90 for Extremely inverse, Very inverse, Normally inverse
and Moderately inverse curves. The formulas that define these curves are as follows:
where:
T = Operation time (in seconds).
Dial = Multiplying factor
I = Input current
I
pickup
= Current pickup setpoint
A, B, C, D, E = Constants
T
reset
= Reset time (in seconds) assuming a 100% of power capacity and that the reset is activated
T
r
= Characteristic constant
The different constants that define the above-mentioned curves are:
Table 5–34: CONSTANTS FOR ANSI CURVES
ANSI CURVE SHAPE A B C D E TR
ANSI Extremely Inverse 0.0399 0.2294 0.5 3.0094 0.7222 5.67
ANSI Very Inverse 0.0615 0.7989 0.34 -0.284 4.0505 3.88
ANSI Normally Inverse 0.0274 2.2614 0.3 -4.1899 9.1272 5.95
ANSI Moderately Inverse 0.1735 0.6791 0.8 -0.08 0.1271 1.08
TDialA
B
I
I
pickkup
-------------------
C–


-----------------------------------
D
I
I
pickup
----------------
C–


2
-----------------------------------
E
I
I
pickup
----------------
C–


3
-----------------------------------
+++=
T
RESET
TDM
T
r
I
I
pickup
----------------


2
1–
----------------------------------
=

GE Multilin F650 Specifications

General

Brand	GE
Model	Multilin F650
Category	Controller
Language	English