hager h3+ - Ground Protection

376LE005550A
Function of the Energy trip unit
3.2 Protection function
3.2.4
Ground protection
Ground protection is protection against high strength insulation faults present in
installations with a TN-S earthing system.
It is independent time protection.
Ground protection curve
In (A)
t (s)
tg
lg
l²tg
Ground protection
Ground parameters
G
Ig (xIn) Ground protection threshold
tg (ms) Ground time delay
i²tg (ON / OFF) Inverse time i²t function
Adjusting the lg threshold
The lg trip threshold can be adjusted from the embedded display, the panel display
or the h3+ configuration tool.
Rating (In) Ig threshold adjustment ranges (xIn) Adjustment step (xIn)
40 A OFF - 0.4 to 1
0.05
100 A
OFF - 0.2 to 1
160 A
250 A
The lg trip threshold tolerance for ground protection is ±10%.
When the Ig threshold is OFF, ground protection is deactivated.
tg time delay
The tg time delay can be adjusted from the embedded display, the panel display or
the h3+ configuration tool.
tg time delay adjustment range (ms)
50 100 200 300 400 500
The trip time tolerance for ground protection is:
- For tg = 50 ms: -30 ms / +30 ms
- For tg ≥ 100 ms: -20 ms / +50 ms