4
PT UNIT USER MANUAL
APRIL 2023 www.eaton.com.cn
2.2 Protection Features
Table 2. Protection Features
Protection
PT 10
PT 20/25
Long Delay
Protection (L)
Curve Slope
I
2
t
I
2
t, I
4
t, I
0.5
t, It
Long Delay Pickup (I
r
)
x (I
n
)
0.4, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9,
0.95, 0.98, 1.0
0.4 to 1.0
Adjustable step is: 0.01
Long Delay Time @ 6 x (l
r
)
Seconds
0.5, 1, 2, 4, 7, 10, 12, 15, 20, 24
0.5 - 24S
Adjustable step is: 0.1S
Thermal Memory
Included
Included
High Load Alarm 1
% x (I
r
)
OFF or % High Load Alarm 2 Adjustable step is: 1.0%
High Load Alarm 2
% x (I
r
)
OFF or % High Load Alarm 1 to 120% Adjustable step is: 1.0%
Short Delay
Protection (S)
Curve Slope
Fixed, I
2
t
Fixed, I
2
t
Short Delay Pickup
x (I
r
)
1.5, 2, 2.5, 3, 4, 5, 6, 7, 8, 10
1.5~ 10S Adjustable step is 0.1S
Short Delay Time 8 x (l
r
) l2t
Seconds
0.1, 0.2, 0.3, 0.5
0.1 ~ 0.5 Adjustable step is 0.01
Short Delay Time Flat
Seconds
0.05, 0.1, 0.2, 0.3, 0.4, 0.5
0.05~ 0.5 Adjustable step is 0.01
Zone Interlock
Enable/Disable
Instantaneous
Protection
Instantenous
x (I
n
)
Off, 2, 4, 5, 6, 7, 8, 10, 12, 15
Off, 2 ~ 15 Adjustable step is 0.1
Neutral Protection
4th Pole or External Neutral Trip
% x (I
r
)
0 (Off), 60, 100
0 (Off), 60, 100
Ground (Earth)
Fault Protection
(Option G)
Ground Fault Pickup
x (I
n
)
Off, 0.2, 0.4, 0.6, 0.8, 1.0
OFF, 0.2~ 1.0 Adjustable step is 0.01
Ground Fault alarm
x (I
n
)
0.2, 0.4, 0.6, 1.0
OFF, 0.2~ 1.0 Adjustable step is 0.01
Ground Fault Delay at
0.625 x (I
n
) l
2
t
Seconds
0.1, 0.2, 0.3, 0.4, 0.5
0.1~ 0.5 Adjustable step is 0.01
Ground Fault Delay Flat
Seconds
0.1, 0.2, 0.3, 0.4, 0.5
0.1~ 0.5 Adjustable step is 0.01
Zone Interlock
Enable/Disable
Thermal Memory
Included
Included
General
Over Temperature Trip
°C
85°C
85°C
Health monitor alarm
%
1~50
1~50
If I
4
t, I
0.5
t, and It slope is selected, not all times are available, consult time-current curves.
These settings on PT10 series modified with PTM.
Only PT 25 supports zone interlocking.
2. Protection and Metering Features
