OTT SLD Series User manual

English
Quick Reference
Side Looking Doppler
OTT SLD

We reserve the right to make technical changes and improvements without notice.

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Table of contents
1 System description 5
2 Parts supplied/components of the OTT SLD 6
3 Preparing for installation 7
3.1 Installing the operating software 7
3.2 Cable connection 7
3.3 Checking the communication 8
3.4 Programming the datalogger 8
4 Installation 9
4.1 Calibrating the pressure sensor 9
4.2 Setting the operating parameters 10
4.3 Aligning the sensor 15
4.4 Checking the water level 17
4.5 Checking the range 17
5 Operation 19
5.1 Disconnecting the PC from the sensor 19
5.2 Connection to datalogger 20
5.3 Verifying the data 21
Appendix A 22
A.1 Technical data 22
A.2 Information on electromagnetic compatibility 23
A.3 Firmware update 23
Appendix B – SDI-12 commands and responses 24
B.1 Basic commands 24
B.2 Advanced commands 30
Appendix C – OTT SLD and Modbus fieldbus protocol 31
Appendix D – Representation of the accumulated discharge volumes 34
D.1 Representation in SDI-12 protocol 34
D.2 Representation in Modbus protocol 35
Appendix E – Installation examples 36
E.1 Example #1 – Installation at a staircase for water level measurement
(mounting rail with slide) 37
E.2 Example #2 – Installation at a staircase for water level measurement
(dual T rail with roller slide) 38
E.3 Example #3 – Installation at a natural river bank slope
(mounting rail with slide) 39
E.4 Example #4 – Installation at a vertical edge wall
(mounting rail with slide) 40
E.5 Example #5 – Installation on a concrete base in the river bed 41
E.6 Example #6 – Installation at a sheet pile 42
E.7 Example #7 – Installation at a vertical edge wall (mounting plate) 43

1 System description
During installation, the sensor is connected to the PC and parameterized using a
serial interface (a). After completing the installation, serial communication is termi-
nated. Thereafter, the sensor is controlled from the datalogger through SDI-12 or
RS-422/RS-485 (b) (SDI-12 protocol).
a) Sensor – Cable – PC/power supply
b) Sensor – Cable – Datalogger/power supply
Fig. 1: Schematic diagram of the
wiring configuration used for setting
the operating parameters.
Fig. 2: Schematic diagram of the wiring
configuration used for measuring.
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2 Parts supplied/components of the OTT SLD
Please check the contents of the shipping crate against the packing list supplied.
The sensor specification may be obtained from the name plate.
Basically, the OTT SLD scope of supply includes 3 items:
Connection cable
Sensor
Operating software CD
The following instrument versions are available:
Discharge
– Measured variables: Flow velocity and water level;
– Built-in discharge calculation;
– Frequencies: 600 kHz, 1.0 MHz, or 2.0 MHz;
– Design: Horizontal or vertical type;
– Interfaces: RS-232 and SDI-12 or RS-422/RS-485 (SDI-12 protocol).
Velocity (flow velocity)
– Measured variable: Flow velocity;
– Frequencies: 600 kHz, 1.0 MHz, or 2.0 MHz;
– Design: Horizontal or vertical type;
– Interface: RS-232 and SDI-12 or RS-422/RS-485 (SDI-12 protocol).
Fig. 3: Components of the OTT SLD.
1 – Sensor head
2 – Sensor housing
3 – End piece with connector socket
The figure shows the "Discharge" instrument
version (measured variable: flow velocity
and discharge); Frequency: 1.0 MHz;
horizontal installation; RS-422/RS-485
interface (SDI-12 protocol).
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3 2 1

3 Preparing for installation
This chapter covers preparing the installation and may be carried out in office.
Within the operating software menus, please use dots instead of commas as
decimal separators (e.g. 1.5m for one and a half meters).
3.1 Installing the operating software
The software is run on the Microsoft Windows XP®operating system or later.
Insert the CD-ROM into the CD drive. Start the "setup.exe" file. Follow the instruc-
tions displayed.
3.2 Cable connection
There are 2 cable options.
a) RS-232 in combination with SDI-12 (maximum 65m);
b) RS-422/RS-485 (SDI-12 protocol) (maximum 500m).
The cables have a coded underwater connector.
Spray the contact pins of the connector and the socket with a silicone spray.
Use the "Scotch™ 1609" silicone spray manufactured by "3M" for this
purpose. Each time you subsequently establish an electrical connection, you
must spray again!
Attach the connector to the plug on the sensor. Secure the connection by
tightening the cap nut (manually – don't use a tool).
The second cable end is open. For communication with your PC, you can
temporarily attach the sub-D socket (9-pin) provided for this open end.
Connect this to your PC's serial interface (possibly RS-232/use a USB adapter).
Connect "+ Supply" to the positive pole and "GND Supply" to the negative
pole of your 12V power supply.
12
56
78
34
0
RS-232
Supply + Supply (typ. +12 V)
GND
SDI-12
RS-232
Not used
OTT SLD
Shielding
RS-232 Rx
RS-232 Tx
SDI-12 Data
SDI-12 GND
12
56
78
34
0
OTT SLD
RS-422
Supply + Supply (typ. +12 V)
GND
Not used
RS-422
RS-422
Shielding
RS-422 Tx–
RS-422 Tx+
RS-422 Rx+
RS-422 Rx–
Fig. 5: RS-422 connection diagram.
Fig. 4: RS-232 connection diagram.
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Please note:
Never grease the contact pins. Risk of corrosion!
Never pull on the cable when disconnecting the connector from the plug!
Handle the connector with care! Avoid unnecessary long-term exposure to
sunlight!
Avoid placing tensile load on the cable!
Do not bend the cable!
Recommendation: Check the connection on a regular basis.
3.3 Checking the communication
Start the OTT SLD EasyUse Software.
From the "Communication" menu, select the "Serial Port" option.
Select "OK" to confirm the "9600" option of the "Baud rate" item.
From "Communication", select the "Connect" option. Now your PC is con-
nected to the sensor.
3.4 Programming the datalogger
Configure your datalogger (refer to the OTT netDL/OTT DuoSens Operating
Instructions). In Appendix B, all SDI-12 commands of the OTT SLD are described.
Make sure that the SDI-12 address of the datalogger matches the SDI-12 address
of the OTT SLD.
Please note: For an OTT SLD "Discharge" instrument version in combination
with an OTT DuoSens, discharge calculation must be performed in the OTT SLD!
There is no option for creating a configuration for calculating the discharge within
the OTT DuoSens.
Fig. 6: Selecting the serial port.
Fig. 7: Setting the baud rate.
Fig. 8: Connection test is successful.
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4 Installation
Please note: Install the OTT SLD in such a way that it will be immersed in water
under any operating conditions. In case this cannot be ensured, provide suitable
equipment for automatically disconnecting the operating voltage when the unit is
"falling dry". Only thus, safe and trouble-free operation of the OTT SLD will be
ensured.
Route the cable from the place of installation of the sensor to the location of the
datalogger. Now repeat all steps described in Chapter 3.
4.1 Calibrating the pressure sensor
The pressure sensor is available only in combination with water level measurement
("Discharge" instrument version).
Calibrate the pressure sensor at the place of installation. The sensor may be
calibrated when it is inside or outside the water.
Perform the following steps:
From the "On-line" menu, select the "Set Pressure Offset" option.
Set the present water coverage of the sensor (outside the water: 0m).
Select "OK" to confirm. The pressure sensor will be calibrated now.
Fig. 9: Set pressure offset.
Fig. 10: Setting the offset.
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4.2 Setting the operating parameters
When you want to create a completely new parameterization,
– select the "Deployment planning"option from the "Deployment" menu;
– select "Load From Instrument", when you want to use the configuration stored
in the sensor.
Select the "Standard" tab and parameterize the following boxes:
Sensor :
Frequency Select the acoustic frequency of the sensor.
Enter the measurement interval. The measurement interval is
triggered by the sensor during serial communication only.
When a datalogger is connected (SDI-12 protocol), this inter-
val is controlled by it. In such a case, leave the measurement
interval of 300 seconds unchanged! Minimum measurement
interval [s] = Flow average interval [s] + Level average
interval [s] + 5 s
River bank Select the river bank side (in flow direction) at which the OTT
SLD is installed: "Left" or "Right". The OTT SLD is designed to
be installed at the right-hand bank side of a flowing water-
way. When it is installed on the left-hand bank side, it will
provide negative flow velocities because of its design. When
"Left" is selected, the OTT SLD will change the sign of the
negative flow velocities the absolute amount of which is,
however, correct.
Fig. 11: "Deployment" menu.
Measurement
interval
Fig. 12: "Deployment Planning"
option, "Standard" tab.
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