Siemens I-T-E Sensitrip MD Series Information And Instruction Manual page 11

MD and ND-Frame Trip Adjustments
Figure 1
I = Maximum circuit breaker ampere rating.
n
I = Current Rating—a function of continuous ampere adjust-
r
ment setting expressed in % of I
Adjustable Instantaneous Trip Switch
x I
r
Instantaneous settings are multiples of the continuous cur-
rent setting.
NOTE: Maximum instantaneous trip is 10,000 Amps—with
instantaneous setting on "MAX", time delay is eliminated.
n
I = Ground Fault Pickup—a function of adjustment setting
g
expressed in % of I .
n
Adjustable Ground Fault Pickup
Pickup I =%I
g n
2
Delay 1 t @ 51n
Ground fault protection is available for 3 phase, 3 wire and 3
phase 4 wire (neutral) electrical systems. SMD/SND models
with an adjustable ground fault delay switch allow for the
selection of ground fault pickup at 20, 25, 30, 40, 55 or 70%
of the maximum amps rating (%I
or .4 sec @ .5 x I See Figure 1 for possible settings for this
n
switch
2
), with an 1 t delay of .1, .2,
n
9