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SE-330HV Neutral-Grounding-Resistor Monitor
Rev. 5-M-101817
2.1.4.5 F
REQUENCY
(S6)
Set switch S6 to 50 or 60 Hz to tune the digital filter to
the line frequency of the monitored system.
2.1.4.6 U
PGRADE
M
ODE
(S8)
The microSD™ card is used for firmware upgrades.
See Section 4.1.2 for upgrade instructions.
N
OTE
: An upgrade causes an SE-330HV restart and this
may cycle the output relays.
2.1.5 R
ESISTOR-
F
AULT
T
RIP
T
IME
The resistor-fault trip time can be adjusted from 12
(default) to 60 seconds using the SE-MON330 software or
via network communications.
2.1.6 R
ESISTOR-
F
AULT
T
RIP
L
EVEL
The resistor-fault trip level can be adjusted using the
SE-MON330 software or via network communications.
See Section 6.1.
2.1.7 G
EO-
M
AGNETIC
F
ILTER
A low-frequency ground current can be caused by the
Earth’s magnetic field and from charged clouds passing
overhead during a thunderstorm. In some rare conditions,
this can cause a false resistor-fault trip. Enabling the geo-
magnetic filter and increasing the resistor-fault trip time
can help counteract these effects.
A trip time of 30 seconds is recommended when the
geo-magnetic filter is enabled.
The geo-magnetic filter is disabled by default, but can
be enabled using the SE-MON330 software or via network
communications.
2.2 C
ALIBRATION
The SE-330HV measures the resistance change of the
NGR relative to the NGR-resistance value determined at
the time of calibration. When the resistance change is
greater than a threshold amount (2,500
Ω
for 100-k
Ω
systems, 5,000
Ω
for 200-k
Ω
systems), a resistor-fault trip
occurs. Calibrate the SE-330HV on new installations, if
the NGR is changed, or if the sensing resistor is changed.
N
OTE
:
If the SE-330HV is not calibrated and is supplied
from the load side of the breaker (non-fail-safe mode),
calibrate within the resistor-fault trip time after power-up
or it may trip and interrupt its supply. See Section 2.1.5.
The CALIBRATION button is located behind the
access cover on the front panel, and it is recessed to
prevent inadvertent activation.
N
OTE
:
Calibration must be performed with the
SE-330HV connected to the sensing resistor and NGR of
the installed system.
To calibrate, press and hold the CALIBRATION button
until the green CALIBRATED LED turns off and returns
to on (if the LED is already off, press and hold until the
LED turns on). Calibration takes approximately two
seconds. If calibration is not successful, a resistor-fault
trip occurs, the RESISTOR FAULT TRIP LED will be on,
the CALIBRATED LED will be off, and the
DIAGNOSTIC LED will flash the calibration-error code.
See Section 2.7.
The SE-330HV may be calibrated remotely using
the SE-MON330 software with the USB interface or the
communications options.
If latching resistor fault (switch S4) is selected, the
calibration-error code flashes until RESET is pressed even
if the CALIBRATED LED is on.
The calibration value is stored in non-volatile memory.
2.3 T
RIP
I
NDICATION
AND
R
ESET
Red LED's and indication relays indicate ground-fault and
resistor-fault trips. The indication relays K2 (GF) 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-
volatile
memory
and
can
be
set
using
the
SE-MON330 software or network communications.
When a trip occurs with latching operation selected, the
SE-330HV remains tripped until reset with the front panel
button or the remote-reset input. See Sections 2.1.4.3 and
2.1.4.4. 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 and
power-up trip memory is defeated even when configuration
switch S2 is set to fail-safe. The maximum automatic reset
time is 2.8 s.
The red DIAGNOSTIC LED annunciates latched
calibration-error and remote trips. See Section 2.7.
When supply voltage is applied with switch S2 set to
FAIL-SAFE, the SE-330HV returns to its state prior to
loss of supply voltage. When supply voltage is applied
with switch S2 set to NON-FAIL-SAFE, SE-330HV trips
are reset. When a local, remote, or network reset is issued,
both trip LED's will flash if they are off.
Resistor-fault-trip reset can take up to one second.
Resistor-fault trip-memory can take up to three seconds after
SE-330HV power up.
2.4 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. 18. 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
