Dynalog C-SCAN 2000 Series Reference guide

www.dynalog.co.uk
SURVEY PROCEDURE MANUAL
Dynalog Electronics Limited
Bristol, England
For Model 2010
Use of Generator and
methods of survey

*Copyright Adobe Corporation **Copyright Microsoft Corporation
Dynalog Software
Please read License Agreement overleaf before installing
Contents
DCAPP 2010 –
This is the software needed to download data from a C-SCAN 2010 or C-
SCAN 2000 unit (See section 9 of survey manual for use).
To install place in CD drive. Installer should autorun. If Autorun fails to start,
open CD from My Computer and double click setup.exe
Folders created on root drive \DCAPP2010 & \DCAPP2010\archive\ &
\DCAPP2010\archive\original
C-SCAN Manuals –
This is all the paper manuals in Adobe*PDF format. You must have Adobe
Acrobat*to read these.
C-SCAN Upgrader –
This is a program that allows C-SCAN firmware upgrades. If you are sent an
upgrade file, this is the program to use. Should you be sent an upgrade, all
instructions for use will be included with the upgrade. Open CD from My
Computer and double click setup.exe
DCAPP for Excel –
This is an older version of DCAPP that is compatible with the C-SCAN 2000
download format (see Section 8 of Survey Manual for use). To Install, open
CD from My Computer and double click install.bat. To run this program, you
will need Microsoft Excel** Version 7 or later
Folders created on C: drive \cscan & \archive\ & \cscandat
Note: The serial communications package must be installed for use. If DCAPP
for Excel shows ‘Object not found’ when download is attempted, install the C-
SCAN upgrader, this will install the serial communications package.

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LeadersinPipelineSurveySystems
C-SCAN SURVEY MANUAL
PREFACE
This manual explains the operation of the C-SCAN System for surveying the condition of the
wrap or coating on buried metal pipelines, and locating faults in the wrap. It is intended for the
use of surveyors with some experience of the survey and maintenance of pipelines.
While the C-SCAN equipment is reasonably robust and weatherproof, it contains delicate
electronic components and should be handled with reasonable care. Wherever possible it
should be transported in its specially designed foam lined case or otherwise protected from
major shocks. The C-SCAN Detector Unit can also be damaged by exposure to some forms
of radiation and to static electricity. Maintenance of this equipment should only be carried out
by qualified personnel using the Manufacturer’s Maintenance Manual.
The material contained in this Manual is copyrighted by Dynalog Electronics Ltd, and is not to
be photocopied, duplicated, or reproduced in any form without the express written consent of
Dynalog Electronics Ltd.
Publication in this manual of information on the design and operation of the C-SCAN
System does not confer any rights to use this information other than for the purpose of
operating C-SCAN equipment supplied by Dynalog Electronics Ltd.
Dynalog reserves the right to make improvements in its products without incurring any
obligation to incorporate such improvements into products already sold.
Specifications, instructions, and other information contained in this Manual are subject to
change without notice.
Any comments, queries or suggestions concerning this manual
should be sent to :
[email protected]
web: www.dynalog.co.uk
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1OUTLINE OF THE C-SCAN SYSTEM............................................................................... 5
1.1 Signal generator ........................................................................................................... 5
1.2 Detector unit.................................................................................................................. 6
2GENERATOR - CONTROLS............................................................................................. 8
2.1 Generator – Front Panel............................................................................................... 8
2.2 Generator – Side Panel ................................................................................................ 8
3GENERATOR - GENERAL DESCRIPTION...................................................................... 9
3.1 Operating environment ................................................................................................ 9
3.2 Power requirements/battery........................................................................................ 9
3.3 Charging the signal generator..................................................................................... 9
4GENERATOR - FIELD OPERATIONS............................................................................ 11
4.1 Connection to pipe ..................................................................................................... 11
4.2 Setting the signal current .......................................................................................... 12
4.3 Pipeline Voltage message.......................................................................................... 13
4.4 Automatic level adjustment....................................................................................... 13
4.5 Apparent problems with Current value .................................................................... 14
4.6 Display details............................................................................................................. 15
4.7 Key sequence for AUTO operation........................................................................... 16
4.8 Key sequence for MANUAL operation...................................................................... 17
5SURVEY PLANNING AND INTERPRETATION OF RESULTS ..................................... 18
5.1 Preparation.................................................................................................................. 18
5.2 Planning....................................................................................................................... 18
5.3 Common fault areas................................................................................................... 18
5.4 Reference readings .................................................................................................... 18
5.5 Distance between survey points............................................................................... 18
5.6 Attenuation values...................................................................................................... 19
5.7 Initial survey................................................................................................................ 20
5.8 Signal range ................................................................................................................ 20
5.9 Fault size......................................................................................................................21
5.10 Minimum distance between survey points........................................................... 21
5.11 Multiple readings..................................................................................................... 21
5.12 Reading accuracy ................................................................................................... 21
5.13 Close interval surveys............................................................................................ 22
5.14 Repeat surveys........................................................................................................ 22
5.15 Long term program................................................................................................. 22
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5.16 High soil resistivities.............................................................................................. 22
5.17 Changes in soil resistivity...................................................................................... 23
5.18 New pipelines .......................................................................................................... 23
6INTERFERENCE AND FIELD DISTORTION.................................................................. 24
6.1 The C-SCAN signal..................................................................................................... 24
6.2 Ground lead interference........................................................................................... 24
6.3 Other signals carried by the pipeline ....................................................................... 24
6.4 Buried metal structures ............................................................................................. 24
6.5 Cross bonds................................................................................................................ 25
6.6 Insulating flanges ....................................................................................................... 25
6.7 Sacrificial anodes ....................................................................................................... 27
6.8 Pipeline Bends and ‘Tees’ ......................................................................................... 27
6.9 Sleeves.........................................................................................................................27
6.10 Effects of ‘Return Current’..................................................................................... 27
6.11 Orientation of Detector to Pipe Axis ..................................................................... 28
7EXAMPLES...................................................................................................................... 29
7.1 Example 1.................................................................................................................... 29
7.2 Example 2.................................................................................................................... 30
8DCAPP 2010................................................................................................................... 31
9FAQ AND OTHER NOTES.............................................................................................. 36
9.1 TR Stations – The need to disconnect ..................................................................... 36
9.2 Generator Connection Problems .............................................................................. 37
9.2.1 Connecting to the Pipeline:................................................................................ 37
9.2.2 Establishing a good Earth:................................................................................. 37
9.2.3 Use alternative Earth connection: ..................................................................... 37
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PRINCIPLES OF OPERATION
An electrical current applied to a well wrapped buried metal pipeline will decrease gradually
with increasing distance from the current injection point, as the current escapes to earth
through the wrapping.
If the wrap has a uniform thickness and separates the pipe from the surrounding soil at all
points, the strength of the signal current on the pipe will decline logarithmically, and the rate of
decline will be dependant primarily on the electrical resistivity of the wrap or coating in use,
and the area of wrap in contact with the soil per unit length of pipe (i.e. for a given coating, the
decline is proportional to the circumference of the pipe).[Note: because of the relative
magnitude of the resistances involved, local changes in soil resistance can usually be
ignored].
If there is a low resistance electrical path from the pipe direct to the soil at any point, there will
be a substantial local increase in the rate of loss of signal current. Such a low resistance path
could arise from: incorrectly applied wrapping, mechanical damage to the wrap before, during
or after installation, decay of the wrap due to soil conditions, disbonding of the wrap from the
pipe (provided that ground water has penetrated into the gap to provide an electrical path to
earth), or a leak in the pipe itself causing the wrap to fail at the leak point.
Because the resistance of such a path is likely to be several orders of magnitude less than
the resistance of the undamaged wrap, the resultant loss of current, even from a single small
fault of a few square millimetres, can usually be detected by a significant increase in the
apparent rate of current decline over quite a long length of pipe.
In practice, the existence of one or two small faults on a section of pipeline several hundred
metres in length can usually be tolerated because the Cathodic Protection System can be
expected to prevent serious corrosion developing quickly. In this case it may not be
necessary to locate the specific faults immediately but the rate of logarithmic decline of
current between two specific points can be logged for future reference so that any
deterioration of the condition of the pipeline can be monitored. [Note: the logarithmic rate of
decline of the current (attenuation) measured in millibels per metre, is effectively independent
of the applied current and is only marginally affected by seasonal changes in soil resistivity,
so that it is virtually an absolute indication of the average condition of the wrap between two
given points at the date of the survey].
If the attenuation level over a given section of pipeline is particularly high, serious faults
(or a large number of small faults) in the protective wrap are indicated. Intermediate readings
of attenuation levels can be taken to identify the worst sections, and the precise location of
faults (generally to an accuracy of 1-2 metres) can be determined by recording and plotting
the actual current levels at close intervals (3-5 metres) over the suspect section and noting
those places where the rate of current decline is steepest. The most serious faults can then
be excavated and repaired.
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1 OUTLINE OF THE C-SCAN SYSTEM
The main elements of the C-SCAN Pipeline Wrapping Evaluation System are the Signal
Generator and the Detector Unit.
The Signal Generator is attached to the pipeline and to an appropriate ground point, and
produces a constant AC signal which passes along the pipe.
The Detector Unit measures the electromagnetic field radiating from the pipeline and uses
this to locate the pipeline, determine the depth of the pipe and the residual strength of the
signal current at the observation point. This data is stored in the memory of the Detector
Unit’s computer and is used to compute and store attenuation rates between any two given
observation points. The complete record of the survey (with time and date) may be printed out
at the end of the survey to provide a permanent record.
1.1 Signal generator
The C-SCAN Signal Generator is a self-contained unit producing an AC signal current of
937.5 Hz.
Battery ISOLATOR switch.
Used when storing for long
periods or for transit by AIR
GROUND
connector- connects
generator to ground
bed or earth spikes
PIPE connector -
connects generator
to pipeline via
cable
Auxiliary Power socket
for connection of
charger OR external 12
volt supply for
extended operation
Pressure relief
valve- press when
lid is hard to open
The output from the Signal Generator is a sine wave signal at a frequency of 937.5Hz, with a
nominal maximum voltage of 60V p-p. The maximum current obtainable is approximately
1.5A. The RMS value of the current being produced is displayed on the LCD on the control
panel, expressed in mA. The actual level of current produced is set by the Surveyor using the
instrument’s controls. Once set, this current level will be maintained at a constant level
(despite any transient changes in soil resistivity) until the batteries are exhausted. In tests, the
unit, when fully charged, has maintained a constant output of 600mA for up to 8 hours
continuous operation when using the internal batteries. Use of an external 12 volt supply can
extend this time indefinitely.
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1.2 Detector unit
The Detector Unit is housed in a weatherproof plastic case.
The front tube contains the antenna system, and the keyboard and LCD display are mounted
on the top of the tube. The base compartment contains the main computer, the batteries and
connectors.
Battery Charger
Input and PC connection
Carrying Handles
Base Unit
containing
batteries
Display
and
Keypad
The antenna consists of a number of large diameter air cored coils.
In operation, the computer calculates the vector sum of the field strengths measured by the
coils over the length of the instrument. The LCD indicates to the operator that it has
‘ACQUIRED’ the signal radiating from the buried pipe. The LCD gives an indication of field
strength and guides the operator towards the pipe. A comparison of the field strengths at the
antenna with the strength of the field measured by the vertical axis, is used to tell the operator
when he is ‘CLOSE’ to the pipeline. When the field measured by the vertical axis coil falls
below a threshold value, the instrument display changes to a moving bar display, guiding the
operator to ‘STOP’ once he is ‘OVERHEAD’.
When the instrument is stationary in the ‘OVERHEAD’ position for a few seconds, it will
automatically collect a sample of 300 readings of the field strength values measured by the
antenna over a period of approximately six seconds. Provided the standard deviation of the
sample is below a threshold value, the computer will then calculate the depth of the pipe
(below the bottom of the unit to the centre line of the pipeline) and the strength of the residual
signal current on the pipe.
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The ‘DEPTH’ and ‘CURRENT’ values (in metres or feet and mA) are shown on the LCD.
Using the keyboard, and following the prompts appearing on the display, the operator can
store the displayed data (which is automatically given a reference number), and request the
computer to calculate the logarithmic attenuation of the signal from any previous location
stored in its memory. This information is displayed on the LCD and is also stored. The
computer can store up to 999 complete sets of data spread over 99 surveys (location
reference number, depth of pipe, strength of signal current, distance from a previous location
reference, and logarithmic attenuation of the signal, in millibels per metre (mB/m), between
the two points). At the beginning of each survey, the computer will also note automatically the
time and date using the internal clock, and this information will also appear on the subsequent
download/printout.
At the end of a survey (or whenever required) the Detector Unit may be plugged into a
standard computer (RS232 serial interface) and the survey report can be printed out in full,
using Dynalog’s DCAPP software.
The Detector Unit is powered by NiMh rechargeable batteries which will normally provide
enough power to run the instrument continuously for over 4 hours. There is, in addition, a
built-in lithium power source to maintain the data stored in the memory when the batteries
have been exhausted. This has an estimated life of ten years.
The C-SCAN System is not immune to electromagnetic interference but it incorporates a
number of features which are designed to keep such interference to an absolute minimum.
Briefly these features include: the generation of a pure sine wave so that no complex
harmonics are produced, the use of a carefully selected frequency with virtually no harmonics
in common with other frequencies in general use, the narrow bandwidth of the filters in the
Detector Unit and the collection of 300 signal samples over a period of approximately 6
seconds to eliminate transient interference. The instrument can usually be used in the
presence of mains AC and is not affected by any residual ‘ripple’ in operating DC (rectified)
Cathodic Protection systems.
Full operational details for the detector can be found in the C-SCAN Operators manual.
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2 GENERATOR - Controls
2.1 Generator – Front Panel
STORE key allows the
present valued to be stored
in memory. Key is also
used in reduce the current
in MANUAL mode.
ON/OFF key – pressing
and holding this key
switches the generator ON.
If the generator is on,
pressing and holding this
key switches off the unit.
A momentary press whilst
active will disconnect the
output.
Auto Select key sets the
output to 600mA OR to the
maximum attainable
current below 600mA.
Pressing and holding key
enters MANUAL mode
where the current can be
manually selected
RECALL key allows
presetting of the output
current to the valued stored
with the STORE key. Key
is also used to increase the
current in MANUAL mode.
2.2 Generator – Side Panel
BATTERY isolator
switch. Use when
storing for long periods
or transit by AIR.
Connection to
EARTH SPIKES
or GROUND
Connection to
PIPELINE
USB Diagnostic /
Upgrade port
CHARGER or
AUXILIARY power
connector
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3 GENERATOR - GENERAL DESCRIPTION
The C-SCAN Generator is a self-contained unit producing an AC signal current of 937.5 Hz.
3.1 Operating environment
The generator is housed in a strong weatherproof plastic case, but it is not designed for total
immersion and is not certified for use in hazardous areas. The Generator will operate
between -20oC and +50oC. The efficiency of the generator is however reduced under extreme
conditions.
As the lid must be open in use, it is advisable to protect it from direct
STRONG sunlight as this will overheat the generator.
3.2 Power requirements/battery
The generator has a built-in re-chargeable lead-acid battery, having a nominal capacity of 17
ampere/hours. The nominal output voltage is 60 volts peak-to-peak (theoretical maximum 62
volts), which is 18 volts rms.
An external 12 volt battery (car battery etc.) can be connected using the cable supplied. This
will extend the usable time to the capacity of the external battery. Note: the external battery
must be charged separately.
The generator is charged by an external power unit which will accept mains power at 110 –
240 volts and at frequencies of 50 Hz or 60 Hz automatically.
A full charge should last for two to three days of normal survey work (depending on level of
signal current). The battery should not be allowed to discharge completely. If possible, the
generator should be put on charge at the end of each day’s survey. This will extend the life of
the battery. When storing for long periods (weeks) it is advisable to isolate the battery using
the isolator switch.
When shipping by AIR the battery MUST be isolated
The generator is supplied in a ‘low charge’ condition and should be fully charged before use.
3.3 Charging the signal generator
Charging is initiated by attaching the charger power unit to the Auxiliary Power connector (see
diagram) and plugging the charger unit into the mains power. Selection of mains voltage
(240,220,110 etc) is automatic. When powered the charger unit will show a green light. This
light is only a power indicator light and does not show charge status.
The generator will automatically switch on and enter the charge cycle. Note that the battery
must be ON (not isolated) – should the ISOLATOR switch be in the OFF position, a warning
will be shown on the screen and the back-light will flash.
The charging cycle is in four stages: Stage 1 charges to 80%. Stage 2 charges to 99%, Stage
3 charges to 100%+ and balances the battery and Stage 4 is the float charge which can
remain active indefinitely.
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Stage 1.
-- CHARGING --
<04:22 Remaining
9.0% Capacity
Stage 1
This stage can last up to 6 hours if the battery is very low. This
message shows estimated time to charge is 4 hours 22
minutes, battery capacity is 9.0%.
-- CHARGING --
<01:52 Remaining
85.0% Capacity
Stage 2
Stage 2.
If the battery is well-used or old, this stage may last the longest
Stage 3.
Checking in 59s
107.2% Capacity
Stage 3
Stage 3 is for top-off or charge balance. A timer will disconnect
the charge such that after 2 minutes the battery is checked for
its ability to hold a charge. If this passes then stage 4 will be
active. Should the battery not hold a charge then a warning
will be given.
!--CHARGED--!
Remove Charger
(Float active)
Stage 4.
Float charge is now active and the charger can be left
attached indefinitely.
To terminate the charge at any time, just remove the charger. NOTE: pressing the OFF key
will prompt you to remove the charger.
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4 GENERATOR - FIELD OPERATIONS
Selecting the Signal Injection Points - It should be remembered that the signal will travel in
both directions from the Signal Injection Point, and that the Detector can operate moving
towards the Generator (when attenuation values will be negative) as well as away from it.
Thus a signal injection point (CP Test Post, etc) in the middle of the section to be surveyed
will probably give better overall results (because of the higher average signal level) than one
at the end of the section. Other points to consider when selecting the signal injection point is
the availability of a good GROUND or EARTH, and the fact that a section of line 10-15 metres
either side of the injection point cannot be surveyed because of mutual interference between
the fields radiating from the GROUND LEAD and the pipe. Thus if it is intended to survey a
road crossing, it is better not to use the CP Test Posts either side of the road to be checked.
Connecting the generator directly to CP transformer/rectifier stations whilst CP is still switched
on has damaged a number of generator units. Despite warnings in the manual against this,
accidents do happen. Dynalog has added new checks to the generator to help guard against
these accidents. Although not foolproof, the new checks should stop 90% of mistakes.
DISCONNECT TR station from
GROUND BED and PIPE
4.1 Connection to pipe
The fully charged Signal Generator should be placed close to the selected CP Test Post (or
other selected signal injection point), and connected to it using one of the short leads,
plugged into the PIPE socket. The other short lead should be plugged into the GROUND
socket. If a CP input position has been selected as signal injection point, the CP System
MUST be switched off, AND the ground bed disconnected, and the GROUND lead should be
attached to the CP ground bed lead.
If a CP Test Post or valve is being used, the GROUND lead should be clipped to one end of
the earth extension lead, and this lead should be taken to a suitable grounding point as far
away as possible from the line of the pipe and at right angles to it. One or more of the
SPIKES should be driven into the ground at this earth point and the earth extension lead
should be attached to them (using the jump leads provided, as necessary).
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Use of existing ground points (other than CP ground beds), such as water pipes, lamp posts,
steel fences, pylons, etc, may be necessary in some situations but must be chosen with care.
If such structures are used as ground points it is essential to ensure that they do not approach
or cross over the pipeline being surveyed at any point.
4.2 Setting the signal current
When pipe and earth connections have been made, the Signal Generator should be switched
ON. The Generator will carry out its own internal checks. When these checks are completed
satisfactorily, the Operator can set the signal current. The flow diagram overleaf outlines the
detector operation.
The signal current is set using either the AUTO or RECALL key. AUTO automatically sets the
current to 600 mA. If the resistance of the ground/pipe circuit is such that 600mA cannot be
attained then the generator will automatically set the current until a good signal is attained. If
the signal is satisfactory, the survey can start. Hold the AUTO to enter MANUAL mode and
choose the current using the ▲▼ keys. When your chosen current is displayed press the
AUTO key again to set the generator to this current. Pressing the RECALL key will set the
generator to the value that has been previously stored.
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4.3 Pipeline Voltage message
Pipeline Voltage
too high!!
Disconnect CP
AUTO to restart
When the current is set and when the generator is switched on,
the generator will check the existing AC voltage on the pipeline
(the AC component of the pipe to soil potential). If this is too
high (greater than 10v rms) then a warning will be shown.
If this warning is given, IT IS ESSENTIAL that the following procedure is carried out to avoid
damage to the generator.
•Disconnect all CP stations and cross-bonds to other pipelines within 1000m
(this should have been done)
•Re-check generator (go through switch on procedure again)
•If the message still appears and indicated voltage is greater than 10v p-p then
there is a foreign signal on the line – DO NOT CONNECT GENERATOR.
•If the message still appears and the voltage indicated on the Generator is less
than 10v p-p, use a multi-meter set to AC current and connect between the
PIPE and GROUND leads (disconnect from generator first). If value is above
100mA rms then there is a foreign AC signal on the line – DO NOT CONNECT
GENERATOR
•If the message still appears and the voltage indicated on the Generator is less
than 10v p-p, use a multi-meter set to DC volts and connect between the PIPE
and GROUND leads (disconnect from generator first). If the DC voltage is
greater than +/-10v – DO NOT CONNECT GENERATOR
•To proceed with the connection press AUTO.
NOTE:
It is the responsibility of the surveyor to check
the pipe-to-soil voltage (AC and DC)
and current (AC) before proceeding.
4.4 Automatic level adjustment
The Automatic Level Adjustment becomes active after 1 minute from setting the current. This
mode is indicated by the message ‘OUTPUT LOCKED’ appearing on the display (see flow
chart).
Once the Signal Current has been set, it will remain constant until the batteries are
exhausted. Any changes in operating conditions during the survey (e.g. changes in resistance
at the EARTH SPIKE due to rain or capillary action) will be automatically compensated for.
This is essential for Current Attenuation surveys.
If conditions change dramatically such that the unit is unable to maintain the correct current,
the unit will set the output to alternate between zero and the maximum attainable every 6
seconds. This will be picked up by the surveyor (the detector operator) alternating as ‘NO
SIGNAL’ then ‘ACQUIRED’ or ‘CLOSE’. This is an indication that the current is no longer
stable and the generator and connections need to be checked.
This usually occurs if the earth spike contact ‘dries out’ making a higher resistance circuit that
the generator is unable to compensate for.
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LeadersinPipelineSurveySystems
4.5 Apparent problems with Current value
The resistances in the generator-pipe circuit define the maximum operating current. The
circuit resistances consist of the following components:
1. Pipe to soil resistance ≈3Ω– usually small because of the large area in contact
2. Generator to pipe connection ≈0Ω– should be zero for good connection
3. Generator to Earth connection – dependent on Earthing system used see section 4.1
If the user is unable to get any current at all i.e. the generator backs off to OFF or displays the
message ‘Output disconnected high resistance’, this is usually because of a high value for
item 3 above.
Earth spike resistance Vs Current mA
1
10
100
1000
10000
0 200 400 600 800 1000 1200
Current (mA)
Resistance (ohms)
The graph above shows the required earth contact resistance for the required current.
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LeadersinPipelineSurveySystems
4.6 Display details
99% 06:49 i25°
GENERATOR OUTPUT
SET to 600mA
16w 10.7v 10Ω
Resistance between Earth
and Pipeline. This includes
the Earth-to-Spike resistance
(this is usually the main
contributor) but excludes
Generator protection
resistance
PEAK voltage on
generator output
Battery state indicator –
Battery symbol replaced
with Xif external power is
used
Power taken by the battery
Internal temperature –
Maximum is 75oC
Estimated survey time
remaining at set current
Batter
y
ca
p
acit
y
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LeadersinPipelineSurveySystems
4.7 Key sequence for AUTO operation
C-SCAN GENERATO
R
Pipeline 0v
99.8%
OUTPUT IS LOCKED
To UNLOCK ▲
SET to 600mA
15w 10.7v 10Ω
OUTPUT UNLOCKED
start NEW Survey
if Output CHANGE
15w 10.7v 10Ω
Switching off!
ISOLATE Battery
When STORING for
Lon
g
p
eriods
On / Off
MANUAL
(HOLD)
AUTO
AUTO for 600m
A
or for MANUAL
Hold AUTO
▲for 1000m
A
AUTO 937.5Hz
TARGET 600mA
100% 16:40
AUTO 937.5Hz
150mA >> 600mA
Checkin
g
100% 08:40
AUTO 937.5Hz
408mA >> 600mA
99.0% 06:12 o27°
OUTPUT LOCKED
SET to 600mA
15w 10.7v 10Ω
1 Minute
99.7% 06:49 i25°
GENERATOR OUTPUT
SET to 600mA
16w 10.7v 10Ω
S
Recall
On / Off
S
Recall
MANUAL
(HOLD)
AUTO
OR
10 Seconds
If no key press
within
1
0
Seconds
Press and HOLD
AUTO to set
MANUAL
Survey may start
From
MANUAL
Operation
To MANUAL
Operation
5 Seconds
To OFF
C-SCAN GENERATO
R
CHECKING OK!
V3.33
Press & Hold
AUTO Operation
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LeadersinPipelineSurveySystems
4.8 Key sequence for MANUAL operation
C-SCAN GENERATO
R
Pipeline 0v
99.8%
On / Off
MANUAL
(HOLD)
AUTO
C-SCAN GENERATO
R
CHECKING OK!
V3.33
AUTO for 600m
A
or for MANUAL
Hold AUTO
▲for 1000m
A
MANUAL use Keys
▼/▲to change
Set to: 600mA
AUTO to SET
100% 08:40
MANUAL 937.5Hz
408mA >> 750mA
HOLD
AUTO to set
MANUAL
MANUAL use Keys
▼/▲to change
Set to: 601mA
AUTO to SET
Press and release ▲
increases current by 1mA S
Recall
MANUAL use Keys
▼/▲to change
Set to: 610mA ▲
AUTO to SET
Press and HOLD ▲
increases current by 10mA
steps S
Recall Note symbol: Shows
increment by 10
Continue to HOLD ▲
increases current by 50mA
steps after next 50mA
boundary
S
Recall
MANUAL use Keys
▼/▲to change
Set to: 750mA
▲
AUTO to SET
MANUAL
(HOLD)
AUTO
Similarly use ▼
To decrease current
T
Store
Or from
AUTO
Operation
Note symbol: Shows
increment by 50
▲
Continue as
AUTO
Operation
Press & Hold
MANUAL Operation
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