2 Design
2.1 Operator interface
12
PXR Electronic trip unit
01/21 MN012005EN
www.eaton.com
2.1 Operator interface
2.1.1 Rotary switch on the PXR10 and PXR20 trip units
Depending on the type of trip unit, there are up to seven rotary switches at
the front of the unit.
Figure 2:
PXR10 and PXR20 overview
Table 2: PXR10 and PXR20 functions
These rotary switches are used to set the protection settings, in line with the
key as indicated. They control the core protection settings. Each rotary
switch has 13 positions and is set in such a way that the corresponding
tripping characteristic will be reached. The “PICKUP” switches (upper row)
set the threshold values for the circuit breaker. The “TIME” switches (t
r
, t
sd
,
t
g
) in the lower row set the delay time in (milli-)seconds. By means of a PZ2
screwdriver or a slotted screwdriver the switches can be adjusted so that the
arrow points to the selected value. For the time functions t
sd
and t
g
, either
the flat or the I²t- characteristic can be selected. The function I
g
can
distinguish between “trip”, “alarm” and “OFF”. If “trip” is selected, the
circuit breaker will trip according to the characteristic curve. If the alarm is
set, an alarm message will either be transmitted via the corresponding
communication register and the
GND
LED, or an alarm message will be sent
via the relay module (if used and configured accordingly).
2
4
6
8
10
11 12 13
14
15
16
17
18
li / nxln
2
3
4
5
6
6.5 7 7.5
8
9
8.5
9.5
10
lr / nxln
lsd / nxlr
tr / s(6xlr)
0.4
0.5
0.6
0.7
0.8
0.9
1
2
5
4
6
7
10 12
8
14
18
20
16
∞
0
0.1
0.02
0.3
0.5
1 0.02
0.75
0.1
0.3
0.5
0.75
1
i
2
*
t
Alarm/ Trip
Ig / nxln
0.2
0.3
0.4
0.6
0.8
0.2 0.3
1
0.4
0.6
0.8
1
OFF
tg / s
0
0.1
0.02
0.3
0.5
1
0.02
0.75
0.1
0.3
0.5
0.75
1
i
2
*
t
tsd / s
Test
Status
SHORT
GND
LONG
INST
85% I
r
/105% I
r
Version
Release
I
r
t
r
I
sd
t
sd
I
i
I
g
t
g
PXR10
-AX(-NA)
✓
–
–
–
✓
–
–
PXR20
-MX(-NA)
✓
✓
–
–
✓
–
–
-VX(-NA)
✓
✓
✓
✓
✓
–
–
-VX-T(-NA)
✓
✓
✓
✓
✓
✓
✓
