Basler Electric BE1-50/51B-218 - Manual (Page 14)

Table 1-3. Time Characteristic Curve Constants with SW3-3 Closed (On)
Curve Type

Constants
BE1 Similar To
Figure
Number † A B C N K R
S GE IAC 55 A-10 0.0286 0.0208 1.000 0.9844 0.028 0.0940
L GE IAC 66 A-11 2.3955 0.00002 1.000 0.3125 0.028 7.8001
D ABB CO-6 A-3 0.4797 0.21359 1.000 1.5625 0.028 0.8750
M ABB CO-7 A-4 0.3022 0.12840 1.000 0.5000 0.028 1.7500
I GE IAC 51 A-12 0.2747 0.1042 1.000 0.4375 0.028 0.8868
V GE IAC 53 A-13 4.4309 0.0991 1.000 1.9531 0.028 5.8231
E GE IAC 77 A-14 4.9883 0.0129 1.000 2.0469 0.028 4.7742
B BS142-B ‡ A-8 1.4636 0.00000 1.000 1.0469 0.028 3.2500
C BS142-C ‡ A-9 8.2506 0.00000 1.000 2.0469 0.028 8.0000
F None § N/A 0.0000 1.00000 0.000 0.0000 0.000 1.0000
Notes for Tables 1-2 and 1-3
 BE1 Curve Types:
S: Short Inverse V: Very Inverse
L: Long Inverse E: Extremely Inverse
D: Definite Time B: BS142 Very Inverse
M: Moderately Inverse C: BS142 Extremely Inverse
I: Inverse F: Fixed Time Delay
† Figure numbers refer to the characteristic curves located in Appendix A, Time Characteristic Curves.
‡ Curves B and C are defined in British Standard BS142 and IEC Standard IEC 255-4.
§ Fixed time delay, adjustable from 0.1 to 9.9 seconds.
Integrating Reset
Reset begins when the current drops below 95% of pickup. Integrating reset simulates the disk reset of
electromechanical relays. BE1-50/51B-218 and BE1-50/51B-228 relays provide the integrating reset
function even when input current falls to zero.
Integrating reset characteristics are defined by the following equation and shown in Figure 1-1. Equation
constants are provided in Tables 1-2 or 1-3.
Integrating Reset Equation:
1 M

RD
T
2
R

Where:
T
R
= Time to reset in seconds
R = Constant for the particular curve
D = TIME DIAL setting
M = Current in multiples of PICKUP setting during reset
1-4 BE1-50/51B-218/-228 General Information 9252000995 Rev H