hager h3+ - Short Time Delay Protection

34 6LE005550A
Function of the Energy trip unit
3.2 Protection function
3.2.2
Short time delay protection
The short time delay protection is designed to protect against short circuits.
Short time delay curve
In (A)
t (s) S
lsd
tsd
l²t
Short time delay protection
Short time delay parameters
s
Isd (x Ir) Short time delay protection threshold
tsd (ms) Short time delay
I²t (ON/OFF) Inverse time I²t function
lsd threshold setting
The lsd trip threshold can be adjusted from the embedded display, the panel display
or the h3+ configuration tool.
Isd threshold adjustment range (x Ir) Adjustment step
OFF - 1.5 to 10 0.5
When the Isd threshold is OFF, the short time delay protection is deactivated.
The lsd trip threshold tolerance for short time delay protection is ±10%.
Adjusting the tsd time delay
The tsd time delay can be adjusted from the embedded display, the panel display or
the h3+ configuration tool.
Isd threshold adjustment range (x Ir)
50 100 200 300 400
The trip time tolerance for short time delay protection is:
- For tsd = 50 ms: -30 ms / +30 ms
- For tsd ≥ 100 ms: -20 ms / +50 ms
An inverse time function I²t = K can be activated or deactivated when adjusting the
short time delay.