Nortroll LineTrol R400D User manual

LineTrollR400D
Pole Mounted Fault Passage Indicator with built-
in Mobile Data Communication.
- SMS
- GPRS
User Manual

This document describes the Installation-, configuration and
use of LineTroll R400D pole mounted Fault Passage Indicator
for Smart medium voltage Distribution Networks
Information in this document is subject to change without notice.
No parts of this documentation may be reproduced in any form by any means without the written permission
of Nortroll AS.
Copyright ©2018 Nortroll AS. All rights reserved. All Nortroll products are trademarks or registered
trademarks of Nortroll AS. Other product names are trademarks or registered trademarks of their respective
holders.
©2018 NORTROLL AS
P.O.Box 133
7601 Levanger
Norway

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User Manual LineTroll R400D
Contents
CONTENTS 3
1. LINETOLL R400D OVERVIEW 5
2. FUNCTIONAL DESCRIPTION. 6
2.1 ADAPTIVE DETECTOR 7
2.2 LOAD CURRENT COMPENSATION 8
2.3 OPERATION 8
2.4 INDICATION 9
2.5 RESET 11
3. WHERE TO MOUNT THE INDICATOR 12
3.1 SUITABLE NETWORKS 12
3.2 MOUNTING RESTRICTIONS 12
4. FAULT DETECTION 14
4.1 LINE SWITCHING –INRUSH BLOCKING 14
4.2 FAULTS 14
4.3 AUTOMATIC RECLOSING 15
4.4 FUSED LINES 15
4.5 MULTIPLE FAULTS 16
4.6 CAPACITIVE DISCHARGES 16
4.7 SETTING THE TRIP LEVEL 17
4.8SENSITIVITY 17
5. EVENT LOG 19
6. FUNCTIONAL DESCRIPTION GSM MODEM 20
INSERTING THE SIM CARD 20
MANUAL ACTIVATION 20
ALARM /MESSAGE RECIPIENTS 20
Sending SMS 21
Sending Flowchart 21
GSM STATUS LED’S22
MESSAGE FORMAT 23
MESSAGE FILTERING 24
POLLING INTERVAL 24
HEARTBEAT INTERVAL 25
OTHER GSM FEATURES 25
GPS 26
7. PROGRAMMING AND SETUP 27
The most important setting to notice: 27
8. MAINTENANCE 28
Battery capacity and monitoring 28
10. TECHNICAL SPECIFICATIONS 29
11. DIMENSIONS 30
12. MOUNTING INSTRUCTION 31
BEFORE INSTALLATION IN THE FIELD 31
MOUNTING 31
RESET 31
TEST 32
MANUAL INSTALLATION 32
REMOTE INSTALLATION 32

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User Manual LineTroll R400D
VERIFYING THE INSTALLATION 32
Manufacturer Notice:
✓From April 2018, Nortroll have changed the LineTroll R400-range
that earlier comprised a –D and –E version to only be supplied as
LineTroll R400D, where the functionality from –E is amended into
the –D version.
✓Please note the importance of using the correct configuration
template matching the firmware in your field device when
configuring the device using NetTroll FDP. By connecting the device
to NetTroll FDP and select “Read All”, an error message will appear if
the template is not correct:
Invalid template Id in data (=260)
The above message means you have to use a template with ID 260
to configure the device.

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User Manual LineTroll R400D
1. LineToll R400D overview
The LineTroll R400D is used to locate short-circuit and earth faults in overhead line
distribution networks. LineTroll R400D is a 3-phase unit fully covering the different fault
situations that may occur.
The indicators are placed at strategic locations along the line such as after branching points
and sectionalisers.
It mounts on the pole, 3-5 meters below the conductors by means of screws or strap-bands.
Live line mounting is done safely, easily and rapidly.
Upon detecting a fault on the line, the indicator starts to indicate the fault with a high visibility
red strobe flash (permanent faults). This flash can be seen within 2000 meters during night
and up to 250m in daylight. It will never be possible to give an accurate distance as it will be
very individual. The lens of the indicator can be turned to either side for optimal visibility. The
indicator does also have separate indications for transient faults and low battery warning.
Figure 1, Indicators in a fault situation
When detecting a fault, all indicators installed between the feeding substation and the fault
will operate. The indicators placed behind the fault remain idle. See figure 1 above.
LineTroll R400D has a built in GSM module which normally is powered OFF, but will wake up
upon a fault and immediately send the alarm to the control center. The operator will therefore
easily identify the faulty section of the feeder, either from Nortroll’s microSCADA system called
NetTroll or from the main SCADA system.
NorTroll also offers system solutions for forwarding alarms to multiple recipients where the
operation central is not staffed 24/7. This program is called NetAlert.
C.B.

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User Manual LineTroll R400D
2. Functional Description.
LineTroll R400D base the fault sensing on detection changes in the electromagnetic field
below the conductors.
The unit is fully self-contained, no external transformers or connections of any kind are
required.
The indicator is looking for a specific sequence in the line conditions to happen before it starts
indicating a fault and send the alarm to the control center. The general sequence is as
follows: (ref. fig.2)
1. The line should be energised for at least 5 seconds. (Inrush blocking time is configurable)
2. The line current should increase rapidly above the value set by the user (the nominal trip
level).
3. The line should be de-energised.
Figure 2. Fault sequence.
I nom
Line
Energized Fault Occurs
BLOCKED READY
15 /30 sec
INDICATION RESE T /
READY
Line
Energized
DETECTION
t
LINE
CURRENT
I trip
5-15 sec
INDICATOR
t
Send
Alarm Send
Reset

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User Manual LineTroll R400D
2.1 Adaptive detector
The measured magnetic field (B-field) is applied to an adaptive dB/dt detector.
Slow variations in the load current will not affect the detector.
A fault current will cause a rapid increase in the B-field which the detector will respond to.
The detector will now require that two conditions are satisfied:
1. The relative increase dB exceeds a configurable level.
2. The absolute increase dB Tis greater than a pre-set value. (Trip level)
Figure 3, magnetic field
It is important to notice that the indicator measure a B-field which is a product of the current
flowing in the feeder. The trip-setting values for short-circuit and earth faults will therefore be
indicative where the values are based on a horizontal line configuration with 1,5m line-spacing
and where the indicator is mounted 3m below the middle conductor.
In triangular, vertical or other line configurations, the distances between each phase and the
indicator will differ. This means the measured B-field change upon a fault will be different and
must be taken into consideration when trip-level is set.
B-field
B-field
NO FAULT EARTH FAULT
I0= 0 I0≠ 0

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User Manual LineTroll R400D
2.2 Load Current Compensation
Traditional fault passage indicators have sensitivity for PtG-faults that depend on the load
current.
High load current causes the indicator to be less sensitive for PtG-faults. In LineTroll R400D,
this problem is overcome with the Load Current Compensation feature (LCC).
Figure 4, Load current compensation
The LCC feature means that the sensitivity for PtG faults will remain unchanged regardless of
the load current. This will result in a more accurate detection of sensitive earth faults and
LineTroll R400D can detect PtG faults as low as 2A.
2.3 Operation
Installation and mounting
The indicator must be calibrated to the normal line conditions during the installation of the
device. This gives the indicator a “picture” of the B-field below the conductors which will be
the basis for detecting changes in the B-field when a fault occurs. This means the indicator
must be installed when the line is energized.
The indicator continuously monitors the load current in order to adjust to the line conditions at
any given time.
Inrush blocking time
Before any faults can be detected, the line must be energized more than 5 seconds. The
inrush restraint algorithm avoids false indication upon energizing of the feeder. (Time is
configurable).
With LCC

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User Manual LineTroll R400D
Fault current
The fault current has to generate the required increase in the magnetic field as described in
section 2.1.
Whether the fault should be indicated and what type of fault should be reported will depend
on what happens after the reclosing period. The setup of the indicator will also affect how the
indicator responds to different fault scenarios.
Circuit Breaker (CB) tripping
The circuit breaker trip criterion gives the indicator one extra criteria for activation and will
give a more accurate detection of a fault.
In networks where the feeder is not tripped upon a fault, the CB-trip criteria must be switched
off.
CB-trip enabled:
Line de-energised within 3 to 15 sec after the fault: ➔Indication
Line not de-energised within 3 to 15 sec after the fault: ➔No indication
CB-trip disabled:
Indication not dependent on de-energised line.
2.4 Indication
LED indication
The LineTroll R400D is equipped with a separate indication board in the bottom lens of the
indicator.
D1 D2 D3
D4
Figure 5, LED indication card
The LED’s are also be used to verify correct installation during calibration. See section for
installation for details. The lens can be adjusted to allow for maximum visibility.
Figure 6, Strobe flash
Low power indication mode for permanent faults
The LineTroll R400D has a low power indication mode where the strong strobe flash is
switched OFF. Instead a separate red LED is used to indicate permanent faults. This will
extend the battery lifetime with approx. two years.
D1: Green; indicates Transient Faults.
D2: Red; indicates Permanent faults if low-
power indication mode is selected.
D3: Amber; indicates Low Battery.
D4: Red strobe flash; indicates Permanent
faults if low power indication mode is
switched off (Default).
The permanent fault indication (D4) is
made as a «strobe» flash with 7 10ms
pulses bursting with a 5 sec interval.

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User Manual LineTroll R400D
The visibility of the local flash will be reduced in this mode, but as the indicator will send all its
alarms on GPRS and/or SMS anyway, the bright strobe flash is maybe not needed and
therefore battery lift-time can be extended as a trade-off for visibility.
Permanent faults
A permanent fault is defined as a fault where the line remains de-energized after tripping
upon a fault. The time the indicator waits until it defines a fault as permanent can be
configured in the range of 40 seconds to 300 seconds.
Fast Auto
Reclosing
Last
Reclosing
Non-successful
Fault
40 to 300 sec5 to 15 sec
SMS with ’Permanent
Fault’
Permanent Fault
Transient faults
A transient fault is defined as a fault where the line is re-energized before the timeout of the
permanent fault timer. The line must be energized longer than 15 to 30 seconds.
Fast Auto
Reclosing
Fault
15/30 sec
SMS with ’Transient
Fault’
Transient Fault
Sending GPRS/SMS alarms and messages
The built-in GSM modem is normally switched off to save battery power. The modem will be
waked up as soon as the indicator have detected a fault and decided whether the fault is
permanent or transient.
The LineTroll R400D connects to the configured APN using a GPRS connection. If this
connection fails and a “back-up recipient number” is set, the alarm will be sent to this number
in an SMS instead. Two other SMS recipients is also possible to configure.
After the unit have sent the GPRS data and/or SMS with the alarm message, the GSM modem
remains powered for a configurable time to receive eventually messages sent to it. (Default
2min). After that it goes back to sleep mode.
Time-stamped events
The LineTroll R400D have a built-in GPS and all events sent to the central will be time-
stamped with a highly accurate time and date.
The time sent will be dependent upon whether the CB-trip criteria are ON or OFF:

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User Manual LineTroll R400D
CB-trip OFF: The time stamp on the message will be the time when the indicator
has validated the fault. The validation time can be set between 3 sec
to 15 sec after a fault occurs.
CB-trip ON: The time stamp on the message will be the time when the indicator
detects that the circuit-breaker has tripped after a fault.
2.5 Reset
The indicator can be reset in four different ways:
1. Voltage reset
The voltage reset can be switched OFF. When switched ON a delay from the line is energized
until the indicator is reset can be set.
The following voltage reset delay selections can be made: 5s, 10s, 15s, 20s, 25s or 30s.
2. Automatic timer-reset
The timer reset can be set to any value between 1,5h and 48h.
3. Manual reset
LineTroll R400D can be reset by turning the lens clockwise to "RESET" position.
A magnet is permanently mounted in the lens.
A special hot-stick-attachable tool is available for resetting of the indicator from the ground
when mounted on a pole.
4. Remote reset
The remote reset feature has limited value as the GSM modem is switched off unless the
indicator has something to send. The reset command will only be received during a polling
sequence, heartbeat message or alarm sending.

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User Manual LineTroll R400D
3. Where to mount the indicator
The best economic benefit is obtained when a line survey is executed before mounting fault
passage indicators.
The indicators should be mounted;
•
To avoid accessing areas difficult to access. (Mountains, forests, private property etc.).
•
To easily locate faulty T-offs. When installing indicators at such points, the use of
indicators in every branch is recommended in order to provide complete information in the
event of fault. Not doing so may cause confusion since there may be an indication from a
branch due to a non-permanent fault while another branch without indicator may be
faulty yet considered healthy.
•
to rapidly identify and isolate the fault to facilitate rapid reconnection the healthy
sections, for example using NorTroll’s actuators for sectionalizing switches. NorTroll’s
actuators for sectionalizing switches. NorTroll’s actuators for sectionalizing switches.
3.1 Suitable networks
The LineTroll R400D fault indicator can be used in the following networks:
✓6 –132kV distribution networks
✓Radial feeders
✓Isolated neutral networks
✓Directly earthed neutral networks
✓Resistance earthed neutral networks
✓Single and 3-phase network
3.2 Mounting restrictions
A pole mounted indicator is only suitable to mount on a pole with no other equipment in the
same pole such as underground cables, T-offs, double circuits, sectionalizers, distribution
transformers, earth wire below the conductors and LV feeders.
In case these requirements cannot be obtained, phase-mounted indicators such as LineTroll
110Er/EQ must be used in these locations.
Adjacent feeders will also affect operation of the LineTroll R400D and the minimum distances
are dependent upon the voltage level as shown in the figure below.
In cases where it is uncertain whether a pole mounded indicator can be used, we would
recommend sending a picture of the mounting position to NORTROLL for verification.

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User Manual LineTroll R400D
>200kV min. 300 meters
132kV min. 150 meters
66kV min. 100 meters
33kV min. 50 meters
22kVmin 35 meters
11kV min 25 meters
Figure 7, mounting restrictions
When LineTroll R400D is mounted in fused lines, special percussions should be taken. See
section 4.4 for details about fused lines.
The indicator should not be mounted on poles near threes or other obstacles. Please contact
NorTroll to clear any doubt with regards to mounting location.

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User Manual LineTroll R400D
4. Fault detection
The aim of this section is to describe how the LineTroll R400D indicator behaves in different
service situations and network events.
4.1 Line switching –inrush blocking
Magnetising inrush current of a line can be
very high, the indicator is provided with a
5 to 15 second inrush blocking (the time is
configurable) of the dB/dt sensor which
prevents it from being activated until the
line current is stabilised.
Once the blocking time has elapsed, the
indicator is enabled for fault detection.
The same inrush blocking will prevent
indication in case of switching against a
fault.
t
t
LINE
I
NO INDICATION
4.2 Faults
Permanent fault
Permanent faults will be indicated by
strong red strobe flash.
The time-out for the indication can be set
by the user in the interval 1.5hour to 12
hours.
If the line is restored within the time-out,
the LED’s will reset, assuming that the
voltage reset is enabled
Fast Auto
Reclosing
Last
Reclosing
Non-successful
Fault
40 to 300 sec5 to 15 sec
SMS with ’Permanent
Fault’
Permanent Fault
D4
When a second fault occurs while indicating the previous fault
If a second fault occurs whilst the LineTroll R400D is indicating a previous permanent fault the
indicator will continue to indicate the first fault. The indicator must be reset before it can
detect the next fault while indicating a permanent fault.

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User Manual LineTroll R400D
Transient (temporary) faults
If the fault is cleared by the automatic re-
closing cycle and the line returns back to
normal service, a single green LED will
flash for a configurable time (2 hours –48
hours). During this period the indicator is
ready to detect new faults. If the new fault
is a permanent fault, the indicator will start
indicating the permanent fault.
4.3 Automatic reclosing
An automatic reclosing will not activate a non-flashing indicator.
If the indicator is indicating a previous fault, the operation due to a reclosing depends on
whether the reclosing is successful or not.
Non-successful reclosing
Closing a breaker onto a fault leads to
another trip almost instantly. When the
indicator already indicates a fault, it needs
to see an energized line for more than a
configurable time before it resets the
indication. The time can be set from 5
second to 30 seconds).
t
t
LINE < 30 s
I
Successful reclosing
The voltage reset feature must be switched ON if the indicator shall reset upon re-energizing
of the feeder. The reset time is configurable. (5 to 30 sec)
4.4 Fused lines
When the circuit breaker trip criteria are switched ON, a three-phase disconnection of the line
is required before the indicator starts indicating the fault.
If only one or two of the three phases are disconnected by the fuses due to a fault, the
indicator will be reset from the remaining not-disconnected phase and no indication will start.
When the circuit breaker trip criteria are switched OFF, the indicator function will depend on
another setting; voltage reset.
If the voltage reset is ON, the indicator will be reset after 5-30sec and the message sent to
the control center will be Transient Fault. The local indication will be with the green LED
flashing for a configurable time.
If the voltage reset is OFF, the indicator will start a permanent fault indication and will be
reset only by the timer, manually or command sent from the control center. The indicator will
report the fault as a permanent fault to the control center.
Fast Auto
Reclosing
Fault
15/30 sec
SMS with ’Transient
Fault’
Transient Fault

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User Manual LineTroll R400D
4.5 Multiple faults
Multiple faults may occur. Defective network components may burn or break due to the
electro-dynamic force of the fault current and cause a second fault.
Another cause of multiple faults in isolated networks is the rise in voltage in the healthy
phases with reference to ground.
The voltage may reach up to 1.7 times the nominal voltage. Weak insulators may not
withstand such a voltage increase, and a second fault may occur on other location of the
feeder.
These kinds of faults may be difficult to trace as they often are non-permanent and only
appear in situations like the ones mentioned above.
4.6 Capacitive discharges
The LineTroll R400D indicator is not directional and detects fault current without
discriminating its direction. In case of an earth fault, the capacitive energy of the network
discharges in the fault point. It should be verified that the capacitive discharge current
downstream the indicator is below the pre-set trip level for PtG faults in order to avoid the
indicator incorrectly activating behind the fault.
In general, capacitive discharge currents can be neglected in solidly earthed systems unless
the total length of the feeder is very long (>50km) and sections of the feeder consists of
underground cable.
If the total capacitive current exceeds the trip level, it is required to change the trip level or
install the indicators in the branching points instead of in the main line. The capacitive
discharge of a branching point is limited by its own capacitance, while in the main line the
capacitive current of all the branches downstream the indicator is added. Underground cables
have larger capacitance than overhead lines. This has to be taken into account when an
overhead line feeds an underground cable.
L1
L2
PEX-cable
L3
Icap= U * LOH
T+U * LC
K
LOH = L1 + L2 (Total lenght of overhead line in km)
LC= L3 (Total lenght of underground cable in km)
T = 300 for resistor earthed (NCR) and Isolated Neutral
T = 900 for solidly grounded neutral
K = 10 for oil impregnated cables
K = 5 for PEX cables
K = 3 for PVC cables
U = Nominal Voltage (kV)
Icap = Capasitive current (A)

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User Manual LineTroll R400D
Calculation example (resistor earthed neutral):
LOH = L1+L2= 20km
LC= 1km PEX cable
U = 22kV
𝐼𝐶𝐴𝑃 =𝑈 ∙ 𝐿𝑂𝐻
𝑇+𝑈 ∙ 𝐿𝐶 𝐾
𝐼𝐶𝐴𝑃 =22∙20
300 +22∙1 5= 5,9 A
In order to avoid activation of LineTroll R400D units installed downstream of the location in the
above example, the trip level for PtG faults must be set to a higher value than 5,9A.
The following criteria have to be met:
𝑰𝒄𝒂𝒑 < 𝑰𝒕 ICap = Capacitive current down-streams of the indicator
It= Sensitivity for Earth Fault (PtG Trip level)
4.7 Setting the trip level
In networks with the feeding transformers neutral isolated from the earth, earth fault current
normally is low.
In such network it is important to do a thorough analysis of the network to find the correct
installation and setting of trip level, especially with regards to capacitive discharge currents.
Basic rules for setting the trip level IT is:
To avoid incorrect detection because of capacitive current from the network down-stream of
the indicator:
IC < IT : where IC = capacitive current down-streams of the indicator.
To ensure correct detection the following has to be met:
IT< IPTG - IC where
IPTG
= the networks total Earth Fault current.
These two rules can be summarised as follows:
IC< IT< IPTG - IC
4.8 Sensitivity
Earth faults
LineTroll R400D monitors the resulting magnetic field below the conductors.
The sensitivity for earth faults is a function of the following variables:
✓The trip level set on the indicator (2, 4, 7, 15, 20, 30, 40 or 50 [A])
✓The line configuration
✓The distance between each phase and the fault indicator
✓The load current at the time of the installation (load current will during fault detection
be neglected by the LCC feature).

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User Manual LineTroll R400D
The nominal trip setting values listed above are calculated values based on the magnetic field
in T (micro Tesla) below a horizontal line configuration with phase spacing of 1,5m and
where the indicators are mounted 3 meters below the middle conductor.
In other configurations, such as triangular and vertical etc, the distance between each phase
and the position of the indicator will differ and the magnetic field sensed by the fault indicator
for the same PtG value will in some instances be changed. In networks with relatively high
earth-fault currents (>10A) this effect will be less significant.
NorTroll offers calculations to be executed on all types of line configurations upon request.
Short circuit faults
The indicator requires that two conditions are satisfied in order to detect a short circuit fault:
1. The relative increase dB is greater than a certain level (50%, 100% or 200%).
2. The absolute dB Tis greater than a pre-set value; 50, 100, 200, 500 or 1000A ref
to an indicator located 3 meters below a horizontal line configuration with 1,5m
conductor spacing. More narrow spacing will increase these values, making the
indicator more sensitive for short circuit faults.
The indicator will indicate short circuit faults the same way as for earth faults and the same
messages (transient or permanent fault) will be reported back to the central unit.
Recommended distances
The fault current which is necessary to
generate a sufficient increase in magnetic
field depends on the;
i) Indicators distance (d) from the
conductor, -measured from the
lowest conductor.
ii) Line configuration
Typical distance is 3-4 meters below the
conductors
d
Figure. 8 Distance from conductors

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User Manual LineTroll R400D
Alignment
Correct alignment of the indicator on the pole is important to ensure correct operation.
Figure 9, Alignment
5. Event log
The LineTroll R400D has an event log where all events such as loss of voltage, transient and
permanent faults etc. are logged and time-stamped.
The LineTroll R400D also does internal checks in the firmware and store results of the checks
in the log.
The log stores the last 128 events and the log can be downloaded and stored in a memory
card and read/presented in a program on a computer.
This program is called NetLogger. Please find details about reading the log in the User Manual
for NetLogger.
The events that can be logged are:
✓Power up reset
✓Temperature (Logged every time the temperature is read)
✓Connection to GSM Network
✓Time set via external radio interface
✓Line is energized (Loss of Voltage Reset)
✓Line is de-energized (Loss of Voltage message)
✓Indicator is reset after a fault by energized line
✓Indicator is reset by timer
✓Permanent fault alarm
✓Transient fault alarm
✓Indicator has detected fault current (Fault Start)
✓Low Battery Alarm
✓Time and position synchronization (GPS)
It is possible to set which messages should be logged and which message not logged by
configuration parameter as described in the configuration manual.
LineTroll R400D LineTroll R400D
CORRECT NOT CORRECT

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User Manual LineTroll R400D
6. Functional description GSM modem
The fault indicator and the GSM modem are integrated units which both are controlled by the
same controller unit and are powered by the same battery source.
In normal operation, when the indicator is ready to detect faults, the GSM modem is switched
OFF to save battery power and to avoid influence on the measurement/detection of the
magnetically- and electrical field.
As soon as the indicator has detected a fault and made it ready to send the correct fault
message back to the central (and start local flash indication), the sensor is switched OFF and
the GSM modem switched ON.
The GSM modem will be awake long enough to send the alarm(s) and to receive messages,
commands or configuration settings sent from the central.
Inserting the SIM card
To find the type of subscription that is most economic and suitable for your system, please
contact your local network service provider.
We do not recommend using prepaid subscriptions. We also recommend disabling voice
communication on the SIM cards as the R400D only use GPRS data and/or SMS.
All PIN codes must be deactivated before installation. Most service providers offer SIM-cards
where the PIN codes are deactivated when delivered.
Manual activation
The GSM modem can be waked up from sleep-mode by pressing the activation button (S1)
>3s. The modem will be online for a predefined time, default 5 seconds.
Alarm / Message recipients
The LineTroll R400D can be set up to report alarms and other messages to a central unit
using GPRS connection. In addition, it can be configured up to three different SMS recipient
numbers.
Insert the SIM-card as shown in the picture
to the left. The batteries should be
disconnected when inserting the SIM card.
Remove the top-cap of the indicators
housing to access:
✓SIM card socket
✓Programming contact (J3)
✓Activation button (S1)
✓Address settings (SW1)