5.3 Connecting humidity absorbing system 5.4 Wire assignment of the pressure probe cable 5.5 Connecting the OTT PLS 500 to any data logger using an SDI-12 interface 5.6 Connecting the OTT PLS 500 to any data logger/electronic control system using an RS-485 interface 5.7 Connecting the OTT PLS to the IP data logger OTT netDL using an SDI-12...
– 2 x 2 x 0.5 mm – shielded 65.050.002.9.2 OTT USB/SDI-12 Adapter – for temporary connection of OTT sensors with SDI-12 or RS-485 interface to a PC – USB connection cable included; USB plug A to USB plug B; 3 m...
▶ Definition Please note: … Information that prevents potential damage or malfunction on the OTT PLS 500. 3.2 Explanation of safety information used The safety information used in these operating instructions is classified according to the nature and severity of a particular hazard. The hazard levels defined are...
Only use the OTT PLS 500 as described in the operating instructions! The intend- ed use of the OTT PLS 500 is to measure the water level and water temperature of natural ground and surface waters (hydrometry). Any other use is not permit- ted! For further information ➝...
This enables comprehensive remote monitoring of the pressure probe. Also, statistical data within each measurement interval will be determined. The OTT PLS 500 can also calculate the current discharge of a water course from the measured water level. This is a special function that can be activated as an option.
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Fig 1: Principal setup of a water level measuring station with pressure probe OTT PLS 500. Attachment hooks (Shown as example: Installation type B – pressure probe suspended; see Chapter 5.2.) Pressure probe cable (e.g. to datalogger) Cable suspension (accessory)
Risk of explosion due to spark formation and electrostatic charge If the OTT PLS 500 is operated in an explosive atmosphere, there is a risk of the atmosphere igniting. This can cause an explosion involving a risk of very severe injury and damage.
Fig. 2 for example. Note: The fine setting of the probe position is carried out, for example, by entering a reference or offset value (see Chapter 6, "Configuring/testing the OTT PLS 500") or using a scaling function of the data logger connected.
Note: The fine setting of the probe position is carried out, for example, by entering a reference or offset value (see Chapter 6, "Configuring/testing the OTT PLS 500") or using a scaling function of the data logger connected. Therefore, in many applica-...
A humidity absorbing system must be installed for drying the surrounding air that enters the pressure compensation capillary of the pressure probe cable! The humidity absorbers OTT FAD 4PF and OTT FAD 6 are available as acces- sories (see Chapter 2, "Accessories"). The OTT FAD 6 humidity absorber also...
SDI-12 interface ■ Connect the OTT PLS 500 to an SDI-12 input of the data logger. Follow the data logger handbook when doing this. Refer to Fig. 4 for the wire assignments of the OTT PLS 500; wires used: red, blue and grey. The maximum cable length is 200 m! Fig.
SDI-12). The maximum cable length is 200 m! ■ Connect the OTT PLS 500 to the IP data logger OTT netDL as shown in Fig. 6 (right). Also follow the operating instructions of the OTT netDL. Variant B: Connect the OTT PLS 500 using a physical RS-485 interface (SDI-12 protocol via physical RS-485 interface).
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Fig. 7 (right). Also follow the operating instructions of the Sutron XL 100/500. Variant B: Connect the OTT PLS 500 using a physical RS-485 interface (SDI-12 or Modbus protocol via physical RS-485 interface). The maximum cable length is 1000 m! Required wire cross section, see Chapter 5.4.
3 satellite transmitter as shown in Fig. 8 (right). Also follow the operating instructions of the Sutron S Variant B: Connecting the OTT PLS 500 using a physical RS-485 interface (SDI- 12 or Modbus protocol via physical RS-485 interface). The maximum cable length is 1000 m! Required wire cross section, see Chapter 5.4.
6 Configuring/testing the OTT PLS 500 The OTT PLS 500 is immediately ready for operation with the standard configura- tion provided by factory settings. In this case, the pressure probe operates – depending on the variant code ordered (see Chapter 2) with the factory settings (see Chapter 7).
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Fig. 9: Changing the factory configuration of an OTT PLS 500 via SDI-12 commands using the "OTT USB/SDI-12 Adapter". OTT USB/SDI-12 Adapter USB connection cable +12 V RS-485 B RS-485 A SDI-12...
All advanced, manufacturer-specific SDI-12 commands on the OTT PLS 500 begin with " ". With these commands it is possible to configure the OTT PLS 500, for example using the "SDI-12 trans parent mode" on a data logger or with the OTT USB/SDI-12 adapter (accessory).
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OTT PLS 500 adds up the status values. Example: +20 ➝ overload pressure sensor (+16) + raw value "temperature" outside the calibrated range (+4); values ≥ +128: exclusively for internal service purposes change sensor orientation intended (e.g.
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Advanced commands (manufacturer-specific) aXSU<value>! Set the unit for level/depth measurements ▶ Read the unit for level/depth measurements aXSU! Factory setting: +0 ➝ m (presetting metric); +3 ➝ ft (presetting imperial) ▶ aXST<value>! Set the unit for temperature values Read the unit for temperature values aXST! Factory setting: +0 ➝...
(company name) mmmmmm – sensor identification – sensor version (in this case firmware) xxxxxxxxxxxxx – additional identification (in this case serial number; max. 13 characters) OTT PLS 500 response 014OTTHYDROPLS500100… …xxxxxxxxxx aAb! b<CR><LF> Change sensor address a – old sensor address b –...
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(≥ 25 % rH) Note If several errors/events occur at the same time, the OTT PLS 500 adds up the status values. Example: +20 ➝ overload pressure sensor (+16) + raw value "temperature" outside the calibrated range (+4);...
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The response to the following aD0! command is extended by a CRC value: a<value1><value2><value3>… …<value4><CRC><CR><LF> a<value1><value2><value3>… aR0! The OTT PLS 500 continuously measures level/pressure, …<value4><CR><LF> temperature and optionally calculates the discharge. This command permits to retrieve measurement results even without the combination of commands aM!/aD0!; for details, see command aD0! after aM!.
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Command Response Description aRC0! a<value1><value2><value3>… The OTT PLS 500 continuously measures level/pressure and …<value4><CRC><CR><LF> temperature, optionally calculates the discharge and requests a CRC value (Cyclic Redundancy Check). This com- mand permits to retrieve measurement results, even without the combination of commands aM!/aD0!; for details, see command aD0! after aM!.
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Command Response Description a<value1><value2><value3>… aR1! The OTT PLS 500 continuously measures level/pressure and …<value4><value5><value6>… temperature and determines statistical values. This command …<value7><value8><CR><LF> permits to retrieve measurement results even without the com- bination of commands aM1!/aD0! … aD2!; for details, see command aD0! …...
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… aD2! command is extended by a CRC value: a<valueX><valueX><valueX>… …<CRC><CR><LF> a<value1><value2><value3>… aR2! The OTT PLS 500 continuously measures level/pressure and …<value4><value5><value6>… temperature and determines meta data. This command per- …<value7><value8><CR><LF> mits to retrieve measurement results even without the combina- tion of commands aM2!/aD0! …...
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CRC (Cyclic Redundancy Check) – sensor address – time in seconds until the sensor has deter- mined the measurement result response OTT PLS 500: 0/1 … 60 seconds – number of measured values response OTT PLS 500: 17 aDB0!
"Start system test" (aV!). This command does not start a sys- tem test! For a description of the response, see command aV! a,<field1>,<field2>,… aIM_00X! The OTT PLS 500 sends meta data for the related measured …<field3>;<CRC><CR><LF> value <valueX> in the form of three data fields. These...
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Command Response Description (Continuation of the description from previous page) <field3> – textual description Last ring buffer pressure/level Mean pressure/level Min. pressure/level Max. pressure/level Median pressure/level Standard deviation pressure/level High accuracy temperature Inside humidity Inside dew point Inside temperature Current orientation Stored orientation Device status Mean temperature pressure sensor...
7.4 Advanced SDI-12 commands Command Response Description ▶ Set/read the unit of level/pressure measured values aXSU<value>! a<value><CR><LF> Set unit aXSU! a<value><CR><LF> Read unit – sensor address <value> – Units for water level measurement +0: m +1: cm +7: mm +2: ft +5: inch The level measurement is carried out with com- pensation of water density/salinity, water temper-...
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9.80659 m/s results. Note The OTT PLS 500 is preset to an average value for Germany (Kassel). The measured value deviation caused by gravitation- al acceleration is ±3 mm in Germany (Flensburg – Oberst- dorf). This measurement error is compensated by inputting the local gravitational acceleration.
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A single measurement takes 250 milliseconds. The averaging time is 0.5 … 59.5 seconds. Single measurement: The OTT PLS 500 is in the idle state by default. An SDI-12 measurement command starts a single measurement interval over the set averaging time. This mea- surement type is available in parallel on the SDI-12- and RS-485 interfaces.
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250 ms 250 ms 250 ms the calculation of the mean value is carried out backwards. The OTT PLS 500 also immediately responds to an aRx! command with a measured value. However it is updated with each individual measurement. 250 ms...
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Measured value= +2.100 m Reference value = +1.500 m Output = +1.500 m (Offset calculated by the OTT PLS 500 and applied to all other measured values = +0.600 m) Notes – A subsequent change of the unit (aXSU<value>!) may result in rounding errors of ±0.001.
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Command Response Description ▶ Reset pressure probe to factory settings including communication settings aXSF+1! a<CR><LF> Reset pressure probe – sensor address Resets all settings – including potentially changed commu - nication settings on the RS-485 interface (Modbus, SDI-12) to factory values (delivery state according to the ordered variant code).
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Command Response Description ▶ Read table entry in rating table (calculation method rating table) aXDR<value1>! a<value2><value3><CR><LF> Read table entry – sensor address <value1> – entry (index) in the table to read out <value2> – water level at related discharge <value3> – discharge at related water level Notes –...
15 14 13 12 11 10 9 IEEE 754 Fraction least float32 range: see IEEE 754 String values Modbus Register Byte 9 10 11 12 13 14 15 E spc S NULL Note: The OTT PLS 500 has only one "Holding Register" Block.
Bootloader version 11 (10) Integer 32 bit V1.23.4 = 123400 (0x0001E208) ▶ Reference system 13 (12) uint 16 0x001 = SHEF 0x002 = OTT physical elements ▶ Reference system 14 (13) uint 16 0x001 = SHEF 0x002 = OTT units ▶...
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Register- Access min. / Register name number Data type Length mode max. Description ▶ Channel 3 – 26 (25) uint 16 water temperature definition of TW, Temperature Water (0x5457) physical element ▶ Channel 3 – unit 27 (26) uint 16 0x0010: °C 0x0011: °F 0x0012: Kelvin...
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Register- Access min. / Register name number Data type Length mode max. Description ▶ Channel 6 – 43 (42) uint 16 compare "Channel1: unit string" unit string ▶ Channel 7 – 46 (45) uint 16 Standard deviation of definition of level or pressure value physical element HA, Height of reading (0x4841)
Register- Access min. / Register name number Data type Length mode max. Description ▶ Channel12 – 71 (70) uint 16 current sensor orientation definition of 0x0001: not defined physical element ▶ Channel 12 – unit 72 (71) uint 16 0x0010: degree ▶...
Register- Access min. / Register name number Data type Length mode max. Description ▶ Channel 9 117 (116) float 32 relative humidity in the probe housing ▶ Channel 10 119 (118) float 32 dew point in the probe housing ▶ Channel 11 121 (120) float 32 temperature of internal...
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The entries in the rating table can be set using the following two tabs. The value table is sorted in ascending order, therefore it is not possible to write directly into the value table. With the aid of the two registers, the OTT PLS 500 controls the correct insertion of the values into the rating table.
(see Chapter 7.2, <value1> in the response to aD0! after aV!). If the humidity rises above this, the OTT PLS 500 outputs error message +64 in the device status (<value9> in response to aD2! after aV!). This is usually an indication of an insufficiently maintained moisture absorber.
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Wear suitable protective gloves during maintenance work! ▶ Observe the application and warning instructions of the scale remover used! ■ Uninstall OTT PLS 500 (see Chapter 5). ■ Remove the black protective cap. ■ Clean the measuring cell carefully using a brush (hard bristles). Lime scale deposits can be removed using a common household scale remover.
Errors that cannot be narrowed down further occur; however, communication on the RS-485-/SDI-12 interface via SDI-12 commands is possible ➝ Perform a system test of the OTT PLS 500 with aV! and retrieve result with aD0! … aD2!. For interpretation of the responses, see Chapter 7.2, aD0!, aD1! and aD2! after aV!.
+49 831 5617-439 repair@ott.com Please note: Only have a defective OTT PLS 500 checked and repaired by the repair center of OTT Hydromet! Under no circumstances carry out any repairs yourself. Any repairs or attempted repairs carried out by the customer will result in the loss of any guarantee rights.
13 Technical data Water level Measuring range Variant 1 0 … 10 m ·33 ft water column /0 ...1 bar Variant 2 0 … 20 m ·66 ft water column /0 ... 2 bar Variant 3 0 … 40 m ·131 ft water column /0 ... 4 bar Variant 4 0 …...
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Product certification FCC/IECS Suppliers Declaration of Conformity (SDoC) FCC Part 15 Rules Section §15.109 The OTT PLS 500 complies with the Eurpean Uninon directives (IEC 61326-1: 2020) applicable at the time of production; For details, see Declaration of Conformity (www.ott.com/resources/)
Annex A – Shorten pressure probe cable If required, you can shorten the pressure probe cable of an OTT PLS 500 indepen- dently. This is useful in all cases, where the local conditions require a significantly shorter cable length (a slightly too long pressure probe cable can also be looped –...
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Fig. A1: Dimensions of the OTT PLS 500 pressure probe cable (picture is not to scale). Fillers Fillers Strain relief Strain relief ✂ Pressure compensation capillary ✂ ✂ Cable shield Cable sheath Pressure probe cable all measures in mm...
Annex B – Note on Declaration of Conformity If necessary, you can download the current version of the Declaration of Confor- mity for the OTT PLS 500 as pdf file from our website: "www.ott.com/resources"!
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