Valeport fastCTD User manual

fastCTD and fastCTD plus
Operating Manual
Document ID
MANUAL-2034990662-4 issue: 1.0
Date:
January 2021
This confidential document was prepared by the staff of Valeport Limited, the Company, and is the
property of the Company, which also owns the copyright therein. All rights conferred by the law of
the copyright and by virtue of international copyright conventions are reserved to the Company.
This document must not be copied, reprinted or reproduced in any material form, either wholly or in
part, and the contents of this document, and any method or technique available there from, must
not be disclosed to any other person whatsoever without the prior written consent of the Company.
© 2021 Valeport Ltd
Valeport Ltd
St Peter's Quay
Totnes TQ9 5EW
United Kingdom
Phone:
email:
Web:
[phone]
[e-mail]
www.valeportwater.co.uk
As part of our policy of continuous development, we reserve the right to alter, without prior notice,
all specifications, designs, prices and conditions of supply for all our equipment

Contents
©2021 –Valeport Ltd
Page | b
Contents
1 Introduction.............................................................................................................................1
2 Sensors..................................................................................................................................2
2.1 Conductivity .....................................................................................................................2
2.2 Temperature - Fast Response Thermistor........................................................................2
2.3 Pressure ..........................................................................................................................2
2.4 Optical Sensors................................................................................................................3
2.4.1 Fluorometers...............................................................................................................3
2.4.2 Turbidity......................................................................................................................5
2.4.3 Field Testing an Optical Sensor...................................................................................6
3 Data Acquisition .....................................................................................................................7
3.1 Sampling Modes ..............................................................................................................7
4 Physical Characteristics..........................................................................................................8
4.1 Dimensions......................................................................................................................9
5 Communications...................................................................................................................10
5.1 Data Telegrams .............................................................................................................10
5.1.1 Recorded File Format................................................................................................11
5.2 Command Codes...........................................................................................................14
5.2.1 Stop Command.........................................................................................................14
5.2.2 Run Commands........................................................................................................14
6 Operation .............................................................................................................................17
6.1 Switch Cap Logger Pack Operation ...............................................................................17
6.2 Bluetooth Logger Pack Operation ..................................................................................17
6.3 Cabled Operation...........................................................................................................18
6.4 Deployment Frame.........................................................................................................18
7 Memory................................................................................................................................19
8 Electrical...............................................................................................................................20
8.1 Changing Batteries.........................................................................................................20
9 SubConn Connector Care ....................................................................................................21
10 Wiring Information ................................................................................................................22
10.1.1 Instrument Connector ............................................................................................22
10.1.2 Mode Pins..............................................................................................................22
10.1.3 Switch Plug............................................................................................................23
10.1.4 Break Out Cable....................................................................................................23
11 Software...............................................................................................................................24
12 Ordering Information.............................................................................................................25
13 EU Declaration of Conformity - CE Marking..........................................................................26
13.1 FastCTD and fastCTD plus............................................................................................27
13.2 fastCTD with Blutooth Option.........................................................................................28

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1 Introduction
An evolution of the miniCTD, the fastCTD Profiler has been designed to deliver the highest quality
CTD casts at fast drop rates as well as conventional casts. A conductivity cell designed for
optimum flow-through, a fast response thermistor temperature sensor and a 0.01% pressure
sensor synchronously sampling at up to 32Hz deliver the highest quality profiles in a lightweight
and robust package.
Add in an integral Fluorometer based on Valeport's Hyperion range, an optional Bluetooth
communications module and the fastCTD plus Profiler offers a unique and versatile solution.

Sensors
©2021 –Valeport Ltd
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2 Sensors
High stability conductivity sensor, which maintains performance at extreme temperatures and
pressures
Fast Response, high accuracy thermistor temperature sensor
High specification, 0.01% of full scale, pressure sensor with a number of pressure ranges to best
suit your operational requirements and maintain the highest possible accuracy
Optional Fluorometer sensor, integrated into the main housing of the profiler
The option for a SubConn connector for wired comms or Bluetooth connectivity options
The Fast Profiler is available with either Titanium or Acetal housing material
2.1 Conductivity
Range:
0 - 80 mS/cm
Resolution:
0.001mS/cm
Accuracy:
±0.01mS/cm
Response Time:
30 milliseconds
2.2 Temperature - Fast Response Thermistor
Range:
-5°C to +35°C
Resolution:
0.001°C
Accuracy:
±0.01°C
Response Time:
50 milliseconds
2.3 Pressure
Range:
10, 50 Bar (Acetal housed systems)
10, 50, 100, 200 Bar (Titanium Bluetooth equipped unit)
10, 50, 100, 300 or 600 Bar (Titanium housed systems only)
Resolution:
0.001% range
Accuracy:
±0.01% range
Response Time:
1 millisecond

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2.4 Optical Sensors
Hyperion Fluorometers are configured and correlated with a specific fluorophore. This is identified
by the letter after the 5-digit serial number and is clearly engraved on the instrument housing
An optical sensor must be kept clean to operate correctly. Ensure that the SWiFT is power down
before cleaning the sensor.
Use warm soapy water with a soft bristled brush to remove any light fouling
For heavy fouling, use a solvent (e.g Isopropyl alcohol) and a soft bristled brush
Always rinse thoroughly after every use in clean, fresh water.
2.4.1 Fluorometers
2.4.1.1 Safety Statement
A Valeport Fluorometer is classified as Risk Group 1 under standard 62471. As the type is
classified as Risk Group 1 solely due to radiation in the visible band a hazard label is not required.
However,
the LED used is in excess of the Exempt Group and that the viewer-related risk is dependent
upon how the user installs and operates the equipment.
The exposure hazard value (EHV) for a Valeport Fluorometer in terms of distance is 320mm.
Never look directly into the optical aperture
2.4.1.2 Chlorophyll a
Performance
Excitation:
470 nm
Detection:
696 nm
Dynamic Range:
0 - 800 µg/l
Instrument Detection limit:
0.025 µg/l*
Actual Detection limit:
0.025 µg /l**
Linearity:
0.99 R2
Response Time:
0.03 to 2 sec
* 3x SD in RO water
** calibrated against Chlorophyll a in acetone solution
2.4.1.3 Fluorescein
Performance
Excitation:
470 nm
Detection:
545 nm
Dynamic Range:
0 - 500 ppb
Instrument Detection limit:
<0.01 ppb*
Actual Detection limit:
0.03 ppb**
Linearity:
0.99 R2
Response Time:
0.03 to 2 sec
* 3x SD in RO water
** Calibrated against Fluorescein solution

Sensors
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2.4.1.4 Rhodamine WT
Performance
Excitation:
520 nm
Detection:
650 nm
Dynamic Range:
0 - 1000 ppb
Instrument Detection limit:
<0.01 ppb*
Actual Detection limit:
0.06 ppb**
Linearity:
0.99 R2
Response Time:
0.03 to 2 s
* 3x SD in RO water
** Calibrated against Rhodamine solution
2.4.1.5 Linear Observation Range
The linear range is the concentration range for which the fluorometer signal is directly proportional
to the concentration of the fluorophore. The linear range starts at the minimum detection limit
(MDL) and extends to the upper limit of the instrument (dependent on fluorophore properties,
optical filters, LED power, sample volume and optical path length).
Valeport Fluorometers have a calibrated linear response for 2 gain settings (e.g. the ranges 0-40
µg/l (G5) and 0-800 µg/l (G1) for chlorophyll a). At higher concentrations, unlike analogue devices
which generally flat-line at full-scale deflection (e.g. FSD 5V) the fluorometer will continue to
output a signal which increases with concentration (i.e. meaningful data), though which is no
longer guaranteed to be linear.
At very high fluorophore concentrations, signal quenching can occur, whereby the instrument
output does not increase linearly with fluorophore concentration (roll-off) and may decrease at
even higher levels.
To perform a quick linearity check, dilute the sample 1:1 with RO water. If the reading decreases
by 50%, the sample is in the linear range. If the reading decreases by less than 50% or even
increases, the sample is above the linear range.

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2.4.1.5.1 Quenching
Quenching refers to the reduction in fluorescence of a fluorophore. Several processes can result
in quenching:
Chloride is known to quench quinine sulphate and Fluorescein. It is, therefore, advisable to
prepare any fluorophore solutions with Reverse Osmosis (RO) or De-Ionised (DI) water.
Temperature quenching - as the temperature of the sample increases, the fluorescence decreases,
that is, fluorescence is sensitive to temperature. In order to improve accuracy, measure the
sample at different temperatures and derive corrections for changes in temperature.
Photo-bleaching (or fading) is the (permanent) degradation of a fluorophore molecule by light
resulting in lower signal levels. Photo-bleaching is dependent on exposure (intensity of light and
duration) and wavelength (UV is more damaging than longer wavelengths). Use of more robust
fluorophores is recommended to avoid photo-bleaching.
2.4.2 Turbidity
Valeport's Turbidity technology is essentially two sensors in one. The first is a “classic”
nephelometer, using a 90˚ beam angle for turbidity levels between 0 and 2000 NTU. The second
sensor uses optical backscatter - OBS (~120˚ beam angle) for turbidity levels beyond 10 000 NTU.
Both sensors output data simultaneously, at a programmable rate, so there is no need to switch
ranges as conditions vary. Intelligent sampling and the use of a 24 bit ADC eliminates the need to
switch gain. The optical head is very compact, measuring just 20mm diameter and is rated to full
ocean depth.
Excitation\Detection:
850nm
Linear Range:
Nephelometer 0 to >1 000 NTU - linear response
Optical Backscatter: 0 to 4 000 NTU - linear response
(>4,000 NTU has a non-linear monotonic response that allows
derivation of higher values using look-up tables)
Minimum Detection Level
0.03 NTU
2.4.2.1 Safety Statement
The Turbidity sensor is classified EXEMPT under the standard 62471.
As a Valeport Turbidity sensor is classified as EXEMPT a hazard label in not required.
Never look directly into the optical aperture

Sensors
©2021 –Valeport Ltd
Page | 6
2.4.3 Field Testing an Optical Sensor
Set the instrument up as required using DataLog x2. There will be a short delay after starting the
instrument as the fluorometer is initiated. Once initiated the light from the sensor will be clearly
visible if the transmition is within the visible spectrum, Turbididty is not and you can, therefore, not
see any transmition –do not look into the sensor apature.
2.4.3.1 Check the following:
The LEDs are on and light is being emitted from the fibres –not Turbidity.
The magnitude of the received data increases when the supplied optical target is held at ~45° to
the sensor window. In case of Turbidity, white paper can be used:
By altering the angle of the target the magnitude of the reading should change thereby showing the
correct operation of the sensor.
If the test target is not available then use a piece of good quality white paper.

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3 Data Acquisition
The fastCTD uses the concept of distributed processing, where each sensor has its own
microprocessor controlling sampling and calibration of readings. Each of these processors is then
controlled by a central processor, which issues global commands and handles all the data. This
means that all data is sampled at precisely the same instant, giving superior quality profile data.
The fastCTD features a selection of pre-programmed sampling regimes, covering many standard
applications. Data may be sampled at up to 32Hz for all sensors, making it suitable for rapid
profiling or for continuous measurement at a fixed point
3.1 Sampling Modes
Three specific sampling modes are available:
Continuous:
Regular and synchronous data collection from all sensors up to 32Hz
Profile:
Data is logged as the instrument descends (or rises), by a user defined pressure difference,
through the water column.
Rapid:
Once the instrument is set to run mode no data is logged until a programmed trigger depth is
reached (e.g. 2 metres below the surface). Completely programmable, the device can be set to
record down cast data only, for example, when the probe stops descending and rises by a
defined amount logging is stopped.

Physical Characteristics
©2021 –Valeport Ltd
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4 Physical Characteristics
Materials:
Acetal or Titanium housing (as specified)
Polyurethane and ceramic sensor components
Stainless steel (316) deployment cage
Depth Rating:
500m (Acetal)
6000m (Titanium)
NB: Maximum deployment depth may be limited by pressure transducer range. The Bluetooth module has
a depth limit of 2000m
Instrument Size:
Main Housing 48mmØ
Sensor Body 54mmØ
Length 370mm (including connector)
496mm with Bluetooth Pack)
Deployment Cage:
110mmØ x 550mm long
Weight (in air):
1.6kg (Acetal) / 3.9kg including frame
2.6kg (Titanium) / 4.9kg including frame
Shipping:
51 x 42 x 27cm
~10kg

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©2021 –Valeport Ltd
4.1 Dimensions

Communications
©2021 –Valeport Ltd
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5 Communications
The instrument is designed to operate autonomously, with setup and data extraction performed
over Bluetooth connection with a PC before and after deployment. Multiple profiles can be taken by
switching the instrument on/off with the magnetic switch key. Bluetooth auto-pairing and discovery
make connecting to the instrument simple and robust..
The instrument can also be supplied with a traditional SubConn connector with a choice of
communication protocols fitted as standard and selected by pin choice on the output connector:
RS232:
Up to 200m cable, direct to serial port
RS485:
Up to 1000m cable
Baud Rate:
38400 - 460800
Protocol:
8 data bits
1 stop bit
No parity
No flow control
5.1 Data Telegrams
Real Time Data is output as columns of comma separated ASCII data
Data output is:
"Ticks"
Units="1/800s"
Counter from start of file, measured in 1/800th's of a
second. To convert to milliseconds, multiply by 800
"Pressure"
Units="dBar"
Depth or Pressure depending on operating units set in
instrument
"Temperature"
Units="°C"
Temperature
"Conductivity"
Units="mS/cm"
Conductivity
"Fluorometer"
Units="ug/l"
Optional depending on whether and which Fluorometer is
fitted.
“Turbidity”
Units=”NTU”
Two fields are transmitted:
optics 1 - Nephelometer | optics 2 -Backscatter
Recorded Data is stored as ASCII text files. It consists of a variable number of colon delimited
header lines depending on the configuration of the instrument, followed by comma separated
ASCII column data as per the real time output.

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©2021 –Valeport Ltd
5.1.1 Recorded File Format
5.1.1.1 Standard fastCTD
Now: 24/02/2020 10:57:32
Battery Level: 1.5V
serial_number: 73503
site_info: VALEPORT TEST SITE
version: 0660713A13 Nov 29 2019 12:06
cal_date: 08/11/2019
address_485: 0
pcb_serial_numbers: 1005509;0
sampling_macro: M1
operational_sequence: 21;13;14;3;1;2
trigger_interval: 0.031250
averaging_time_constant: 1.000000
trigger_count: 32
conductivity_sync: -9.751544e+34;2.002785e+08
conductivity_cal: 0.000000e+00;1.320966e-03;-1.689269e+00
temperature_sensor_type: 1
temperature_adc_res_cal: -2.719027e+12;8.304032e+05;1.678985e+02;-9.990086e-06
temperature_cal_steinhart: 6.432787e-04;2.269408e-04;0.000000e+00;6.966944e-08
temperature_correct_press: 0.000000e+00;0.000000e+00;0.000000e+00
pressure_cal: -1.443702e-13;1.003170e-04;-2.843256e-02
pressure_units_id: 0
pressure_units_label: dbar
pressure_units_scale_per_dbar: 1.00000
pressure_ser_no: 0
Profile_pressure_step: 10.000000
Rapid_trip_start: 10.000000
Rapid_trip_stop: 1000.000000
latitude: 50.00000
longitude: 0.00000
pressure_tare_dbar: 0.000
pressure_tare_mode: 1
user_output_stats_ID: 0,24
label: ticks,pressure,temperature,conductivity
units: 1/800sec,dbar,deg C,mS/cm,
1387,09.988,19.777,00.058
2150,09.982,19.789,00.057
2950,09.982,19.746,00.057

Communications
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5.1.1.2 fastCTD plus (Fluorometer)
Now: 21/01/2021 15:15:11
Battery Level: 1.4V
serial_number: 45716.000000
site_info: Valeport Test Site
version: 0660713A0 Jan 13 2015 12:15
cal_date: 00/00/2000
address_485: 1
pcb_serial_number: 0
operational sequence: 13;14;3;1;2
trigger_interval: 0.031250
averaging time constant: 1.000000
trigger_count: 32
temperature_sensor_type: 21
temperature_adc_res_cal: -1.941120e+13;8.349707e+06;1.632860e+02;-9.741146e-06
temperature_cal_steinhart: 6.388685e-04;2.268763e-04;0.000000e+00;7.224784e-08
temperature_cal_secondary: 0.000000e+00;“.483648e-43;“.483648e-43
pressure_ser_no: 1
pressure_trip_step: 10.000000
pressure_trip_start: 9.000000
pressure_trip_stop: 2.000000
pressure_tare: 10.114415
pressure_tare_mode:
user_output_stats_ID: -1,-1
fluoro_gain: 4
fluoro_sync_measure_duration: 1.000000
fluoro_high_lightlevel: 235
fluoro_cal_coefficients: 1.000000e+00;0.000000e+00;0.000000e+00
columns:time,pressure,temperature,conductivity,fluorometery,
units:1/800sec,dbar,deg C,mS/cm,ug/l*,
1729,00.001,23.245,-0.003,305.925
2500,00.002,23.247,-0.003,171.626
3300,00.001,23.246,-0.003,190.889
4100,00.002,23.248,-0.004,203.170
4900,00.002,23.249,-0.004,117.875
5700,00.002,23.249,-0.004,227.219
6500,00.001,23.251,-0.004,208.928
7300,00.002,23.256,-0.003,246.401
8100,00.002,23.261,-0.003,282.974
Notes:
*units will depend on the fluorophore.
Negative fluorophore observations indicate excessive ambient light conditions and although valid
readings should be considered potentially 'compromised'.

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5.1.1.3 fastCTD plus (Turbidity)
Now: 22/07/2020 10:16:49
Battery Level: 1.5V
version: 0660723A4
SerialNumber: 72149
CalDate: 26;9;19
SiteInfo: 181399
OperationSequence: 21;13;14;3;1;2
AveragingConstant: 0.500000
PcbSerialNumber: 0
DataStartTime: 2020/06/07 13:12:00
OpticsOffPressure: 1000.000000
TemperatureSensorType: 1
TemperatureAdcResCal: 0.000000e+00;0.000000e+00;1.679056e+02;-9.993171e-06
TemperatureAdcSelfcal: 0;0;0
TemperatureCalSteinhart: 6.308661e-04;2.275197e-04;0.000000e+00;7.016017e-08
temperature_function: -4.050001e-05;0.000000e+00;0.000000e+00
PressureSerNo: 194326
InstrumentType: 2
PressureTripStep: 0.500000
TemperatureUseSelfcal: 1
PressureTripStart: 0.010000
PressureTripStop: 1000.000000
OutputTripMode: 0
BluetoothTrip: 0
BluetoothTripOnPressure: 40000.000000
BluetoothTripOffPressure: 40000.000000
UserOutputStatsId: -1;-1
PressureCalCoef: -9.433292e-14;1.002338e-04;-3.892180e-02
PressureTare: 10.251189
PressureTareMode: 1
PtoPcbSerialNumber: 0
Latitude: 50.427433
Longitude: -3.681510
OutputMode: 1
LastSamplingMode: M2
UserOutputCount: 4
TemperatureSerialNumber: 9005
PressureType: 3
OpticsOpticsChan1Calibration: 0.000000e+00;9.671701e+00;
OpticsOpticsChan2Calibration: 0.000000e+00;1.774800e+02;
OpticsPcbSerialNumber: 170316;
OpticsSyncMeasureDuration: 0.062500;
OpticsTriggerCount: 1;
OpticsTriggerInterval: 0.062500;
OpticsParameterId: 8;
OpticsParameterUnits: NTU
OpticsHeadSerialNumber: 159167;
label: Ticks,Pressure,Temperature,Conductivity,Optics1,Optics2
units: 1/800sec,m,degC,mS/cm,NTU,NTU
1261 00.00019.66500.00400.19001.652
1631 00.00019.69300.00400.30700.559
2031 00.00019.68500.00400.48002.449

Communications
©2021 –Valeport Ltd
Page | 14
5.2 Command Codes
The fastCTD is designed to be used with Valeport’s DataLog X2 software. However, the
instrument will respond to a series of text commands that are detailed here. Note that this list is not
comprehensive, but will allow the standard functions of the instrument to be accessed. For more
detailed information, please contact Valeport Ltd.
Notes
All commands must be confirmed using “Carriage Return” or “Enter” on the keyboard, with the
exception of the “Stop” command (#).
All commands are echoed back by the instrument as they are typed
5.2.1 Stop Command
The instrument can be stopped at any time by sending the ‘#’ character. The instrument returns a
‘>’, and waits for a further command.
5.2.2 Run Commands
R1
Collects rapid profile at 1 Hz
R2
Collects rapid profile at 2 Hz
R4
Collects rapid profile at 4 Hz
R8
Collects rapid profile at 8 Hz
R16
Collects rapid profile at 16 Hz
R32
Collects rapid profile at 32 Hz
M1
Performs continuous measurement at 1Hz
M2
Performs continuous measurement at 2Hz
M4
Performs continuous measurement at 4Hz
M8
Performs continuous measurement at 8Hz
M16
Performs continuous measurement at 16 Hz
M32
Performs continuous measurement at 32 Hz
Running at high update rates will provide increased temporal sensitivity but will result in noisier
data, especially optical.

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Command
Notes
Pn.nn
Performs profile at a depth increment of n.nn, as set by the operator, in the
current profiling units (see command #018). e.g.: P0.25 takes a reading
every 0.25 dBar, metres or feet as appropriate
Rapid Profile Settings
#812;NN.N
Start Depth (Logging on)
#813
Report Start Depth
#814;NN.N
Stop Step (Logging off when depth decreases by amount. Should signify
bottom of profile.)
#815
Report Stop Step
Bluetooth Power Saving Mode
#820;0
Bluetooth Power Saving mode off
#820;1
Bluetooth Power Saving mode on
#824;NN.N
Bluetooth off Depth
#825
Report Bluetooth Off Depth
#822;NN.N
Bluetooth on Depth
#823
Report Bluetooth On Depth
Fluorometer Power Saving
#434;0
Fluorometer Power Saving mode off
#434;1
Fluorometer Power Saving mode on
#436;NN.N
Fluorometer off depth
Pressure Units
#018;0
Pressure is output in dBar
#018;1
Pressure is output in metres, calculated using simplified UNESCO formula
#018;2
Pressure is output in feet, calculated using simplified UNESCO formula
Pressure Tare
#009;
Takes a single reading of the pressure sensor and uses the measured value
as a Tare (note the ‘;’ in the command)
#009;nn
Sets the Pressure Tare to ‘nn’, a user specified value (entered in the chosen
units as set with command #018)
e.g: #009;10.3 sets Pressure Tare to 10.3 dBar metres or feet.
#010
Instrument responds with current Tare value

Communications
©2021 –Valeport Ltd
Page | 16
Command
Notes
Site information
#037;info
Each data file may contain up to 58 characters of information about the
deployment. Each file will use the same information until it is updated.
#038
Instrument responds with current site information
#016;lat
Sets the instrument deployment latitude in decimal degrees, for use in
pressure / depth conversion algorithm
#017
Instrument responds with current latitude information
#022;long
Sets the instrument deployment latitude in decimal degrees
#023
Instrument responds with current longitude information
Instrument Information
#032
Instrument responds with its software version number
#034
Instrument responds with its serial number
#138
Instrument responds with date of last calibration
Logger Control
$DIR
Outputs file table (list of data files)
$CLR
Clears memory (use with caution!)
$OCLK
Reads Current Date & Time
$ICLK;DD;MM;CC;YY;HH;MM;SS
Sets Date & Time
e.g.: $ICLK;03;02;20;08;14;30;00 sets clock to 14:30:00 on 3rd February
2008
$DEL;filename
Deletes specific file e.g.: $DEL;File1
$EXTT;filename
Performs simple text output data contained in specific file
$EXTZ;filename
Performs Zmodem extraction of data contained in specific file
$RN;filename;newfilename
Renames a file e.g.: $RN;File1;MyData
$FREE
Outputs amount of free memory
$VOLT
Reads internal and external voltage levels

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6 Operation
6.1 Switch Cap Logger Pack Operation
If the fastCTD is supplied with a standard logger pack and connector, it will be also supplied with a
SubConn Switch Cap. This is a dummy connector plug has pins 1 & 10 linked. Inserting the
switch cap into the instrument connector activates the instrument and it will begin logging data in
the last configured mode. It will continue running until the plug is removed, or the battery is
exhausted.
6.2 Bluetooth Logger Pack Operation
The Bluetooth miniLogger pack has been designed as a direct replacement for the standard
SubConn miniLogger pack. The Bluetooth miniLogger is rated to 2000m and is secured using the
same lock ring as used by the standard logger pack.
On first installation, it will require 2 minutes to initialise, during this period the magnetic switch-key
should be removed.
After initialisation the switch-key can be used to turn the instrument on and off in the same manner
as the SubConn switch-cap is used on the standard logger pack. Every time the switch is removed,
the instrument will start a new file.
To ensure the reliability of the Bluetooth communications, the logger pack is supplied with a
dedicated Bluetooth receiver. The logger and receiver are paired in the factory and will
automatically connect whenever active and in range. The receiver is supplied with a stubby aerial,
but can also be supplied with a weatherproof magnetic mount antenna for outside mounting

Operation
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Page | 18
The receiver will install as a USB serial port adaptor and should install automatically on most
windows PC’s. If the receiver will not automatically install, drivers can be downloaded from:
Once installed, the device will scan for the paired logger, with the LED cycling from green to
purple. When the logger pack is detected, the LED will go blue. If data is being transmitted then the
LED will flash blue.
Once the device is connected, it can be communicated with as though connected with a cable.
When using DataLog Express, the Bluetooth option should be checked.
For use with hyper terminal, the connection is 57600 baud, 8 N 1.
For use with DataLog Express, select the Bluetooth Comms option which fixes the baud rate to
57600 baud, 8 N 1.
6.3 Cabled Operation
If the fastCTD is supplied with a standard logger pack, it will be also supplied with a 3m Y lead.
Connecting the Y-lead to the instrument will switch the fastCTD on, where it can be configured via
the DB9 connector attached to a PC serial port.
If the Y-lead is connected without supplying an external power source (9-30V DC), the instrument
will remain on until the battery is exhausted.
6.4 Deployment Frame
Unless specifically requested the fastCTD is calibrated in its frame. It should be operated while in
the frame and lined up as it was when calibrated.
If removed from the frame the fastCTD should be returned to it before deployment. There is a
central slot in the fixed clamp of the frame which should be aligned with the spot on the tube as
shown in the picture above. Align as described and tighten with an Allen key.