Littelfuse SE-330AU, Руководство пользователя

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Page 4
SE-330AU Neutral-Earthing-Resistor Monitor
Rev. 4-I-101817
2.4 T
RIP
I
NDICATION AND
R
ESET
Red LED's and indication relays indicate earth-fault
and resistor-fault trips. The indication relays K2 (EF) and
K3 (RF) operate in fail-safe or non-fail-safe mode. The
default is non-fail-safe mode. In this mode, the relays are
energized when a fault occurs. The relay mode setting is
stored in non-volatie memlory and can be set using the
SE-MON330 software or network communications.
When a trip occurs with latching operation selected, the
SE-330AU remains tripped until reset with the front panel
button or the remote-reset input. See Sections 2.1.4.1 and
2.1.4.2. Terminals 15 and 16 are provided for remote
reset as shown in Fig. 3. The reset circuit responds only
to a momentary closure so that a jammed or shorted
button does not prevent a trip. The front-panel RESET
button is inoperative when terminal 15 is connected to
terminal 16. If non-latching operation is selected, trips
and corresponding indication automatically reset when the
fault clears. Resistor-fault-trip reset can take up to one
second.
The red DIAGNOSTIC LED annunciates latched
calibration error and remote trips. See Section 2.8.
When supply voltage is applied, the SE-330AU returns
to its state prior to loss of supply voltage. A resistor-fault
trip-memory trip can take up to three seconds after
SE-330AU power-up.
2.5 R
EMOTE
O
PERATION
Relays K2 and K3 can be used for remote indication,
and terminals 15 and 16 are provided for remote reset.
RK-332 Remote Indication and Reset components are
shown in Fig. 19. Connect them as shown in Fig. 3.
RK-332 components are not polarity sensitive.
Indication relays can be set to fail-safe or non-fail-safe
operation using the SE-MON330 software or network
communications. The default mode is non-fail-safe. In
non-fail-safe mode, relays energize on fault.
Network-enabled SE-330AU’s can be remotely tripped,
reset, and calibrated by the network master. The red
DIAGNOSTIC LED indicates a network-initiated trip.
See Section 2.8. Refer to the appropriate SE-330AU
communications manual.
2.6 R
ELAY
K1 LED
The yellow RELAY K1 LED follows the state of relay
K1 and is on when K1 is energized (contact closed).
2.7 U
NIT
H
EALTHY
O
UTPUT
UNIT HEALTHY relay K4 is energized when the
processor is operating. It can be ordered with N.O. or
N.C. contacts. See Section 7.
N
OTE
: The K4 output changes state momentarily during
a processor reset.
N
OTE
: K4-contact rating is 100 mA maximum.
2.8 D
IAGNOSTIC
LED
The DIAGNOSTIC LED is used to annunciate trips
without individual LED indication. The number of short
LED pulses between two long pulses indicates the cause
of the trip.
By default, both critical and non-critical diagnostic
flash codes are shown. Non-critical diagnostic codes
include SD Card status and USB Error status. All other
diagnostic codes are considered critical.
Starting with SE-330AU firmware version 2.60 and
SE-MON330 software version 3.8, the SE-330AU can be
configured to show only critical diagnostic codes. In this
configuration, non-critical diagnostic codes will not be
indicated with the DIAGNOSTIC LED.
Diagnostic messages are always visible with the SE-
MON330.
See Sections 4.2 and 5.
2.9 A
NALOG
O
UTPUT
An isolated 4–20-mA output indicates NER current
with full-scale output corresponding to the CT rating. An
internal 24-Vdc supply allows the analog output to be
connected as a self-powered output. Power from an
external supply is required for loop-powered operation.
See Fig. 2. The PGA-0520 analog meter can be panel-
mounted to display the NER current. See Fig. 20 and
Section 7.
FIGURE 2. Analog-Output Connections.