Applications
3.3 Motor protection applications of 3VA molded case circuit breakers
3VA molded case circuit breakers with IEC certificate
Manual, 03/2019, A5E03603177010-03
159
3.3.4.1
ETU550M electronic trip unit
Motor protection - function LSI
The ETU550M electronic trip unit features:
●
Adjustable parameter setting I
r
for overload protection (L)
●
Adjustable parameter setting I
sd
for short-time delayed short circuit protection (S)
●
Fixed parameter setting t
sd
for short-time delayed short circuit protection (S), t
sd
= 0.03 s
●
Adjustable parameter setting I
i
for short-circuit protection (I)
●
Adjustable parameter setting T
c
for the trip class or tripping time T
p
●
Adjustable parameter setting for phase unbalance from 5 to 50% / Off, t
unbal
ETU550M setting parameters
