background image

 

OMC-042 / 043 / 044 Data loggers

 

Users

’ manual

   

page 73 

Using Load Cells with the OMC-042 

The OMC-042 is very suitable for connecting load cells and other resistive elements. A load cell acts as a 
bridge of Wheatstone and is a very sensitive and precise passive component. 

Bridge of Wheatstone 

 
The bridge of Wheatstone (the principle of operation of a load cell) is a circuit, consisting of 4 resistors. 
Below a circuit is given: 

 

Given, all R’s are the same the output voltage will be 0 Volts. In practice, one of the resistors is replaced 
by a variable resistor (often a strain gauge). By varying the resistance of this resistor, the bridge will be 
“unbalanced” and there will be an output Voltage, other than 0 Volts. To enable the circuit, the bridge has 
to be powered by a very stable reverence Voltage, often called “Excitation Voltage”. The OMC-042 has 
an Excitation output for this purpose. 

 Excitation Output. 

The OMC-042 has an Excitation output for powering load cells, or other devices. It is a single output with 
a fixed precision voltage output. This Excitation output is driven by the Power Switch of the OMC-042.The 
default, fixed, Excitation Voltage is 5.000 Volts. For most load cells, this is OK. However, if the user 
wishes another value, it can be selected by selecting 3 soldering jumpers on the bottom side of the board. 
 
Here is how to set the jumpers for the correct Excitation Voltage: 
 

Excitation Voltage Configuration 

SJ1 

SJ2 

SJ3 

Voltage 

Open 

Closed 

Open 

2.500 V 

Closed 

Open 

Open 

5.000 V 

Open 

Closed 

Open 

7.500 V 

 
The default excitation is 5.000 V 

 

 

 

 

Summary of Contents for OMC-042

Page 1: ...OMC 042 OMC 043 OMC 044 Low power 2G 3G 4G data loggers Title User Manual OMC 042 OMC 043 OMC 044 Date April 2021 Version FW 2 4 ...

Page 2: ...you to install it and tells you how to put it into operation The Chapter Operating Basics covers basic principles of operation of the data logger The operating interface menu and the tutorial examples rapidly help you to understand how your data logger operates The Chapter Reference teaches you how to perform specific tasks and provides a complete list of operating tasks and useful background info...

Page 3: ...e factor 25 Value offset 25 Decimals 25 Data log 25 Data transpond 25 Alarm SMS 25 Alarm log 25 Alarm output 26 Alarm limits and delays 26 Configuration Menu Settings 27 Date Time 27 System Information 27 Configuration Setup 28 General Settings 28 Exit 28 System Name 29 Datalog interval 29 Normal mode 29 Alarm mode 29 Timestamp round down 29 Continuous Alarm Sampling OMC 043 044 only 29 Digital Al...

Page 4: ...5 Sensor power switch 35 Sample interval 35 Port mode 35 Parameter settings 35 Value at 0 4 20 mA or 0 10 V 35 Determine linear conversion function 2 calibration points 35 Determine linear offset only 1 calibration point 35 Digital Sensors pulse input 36 Sample interval 36 Port mode 36 Pull up 36 Pull down 37 Register mode 37 Units per pulse or pulses per unit 37 Register value 37 Register Reset 3...

Page 5: ...pow x y 43 clip x min max 43 Supported comparisons with 2 arguments 44 lt x y 44 le x y 44 gt x y 44 ge x y 44 Supported comparisons with 4 arguments 44 eq x y q p 44 lt x y q p 44 le x y q p 44 gt x y q p 44 ge x y q p 44 Serial Port 45 RS232 45 Generic Modbus RTU 45 Port Settings 45 Register type 46 Register Start address 46 Data Type 46 Generic Serial 47 Log raw data String 47 Decimal symbol 47...

Page 6: ... 54 Latitude Longitude 54 GPS Quality 54 Camera 55 Display 56 Power down delay 56 DTU Connection OMC 043 044 only 57 Port Settings 58 Sensor Power Switch 58 Connect interval 58 Connection Delay 58 Server 58 TCP Port 58 Client ID 58 Termination ID 58 Terminal Request ID 58 Email output 59 Server 59 SMTP port 59 Originator address 59 Destination address 59 Data format 59 FTP Output 60 Server 60 FTP ...

Page 7: ...0 10 V OMC 043 044 only 72 Analog Differential Inputs OMC 042 only 72 Differential input ports theory of operation 72 Common mode noise rejection 72 Using Load Cells with the OMC 042 73 Bridge of Wheatstone 73 Excitation Output 73 Analog Differential input 5 74 Analog Differential input 6 74 Calibration of Differential inputs 74 Overall Calibration 74 Potmeter input OMC 043 044 only 75 Digital inp...

Page 8: ...ery Life 89 Pin configuration 90 OMC 042 90 OMC 043 91 Pin descriptions 92 Analog Inputs 92 Analog Input 1 to 4 OMC 042 or 1 to 2 OMC 043 92 Analog Input 3 to 4 OMC 043 92 Analog Input 5 OMC 043 92 Analog Input 5 to 8 OMC 042 only 92 RS485 A B 92 Power Switch 92 VBAT 92 RS232 RX TX 92 SDI 12 Hi 92 Digital inputs 92 3V6 93 Antenna placement and field strength 93 Maintenance and Repair 94 RTC Lithiu...

Page 9: ...ent loop inputs voltage inputs resistance inputs and digital inputs They can also be provided with an RS232 RS485 SDI 12 port to capture serial data ASCII MODBUS RTU NMEA 0183 SDI 12 or to connect an accessory Camera Display GPS Satellite modem External sensors can be powered by the data logger itself to prevent them to consume power while the data logger is asleep The excitation voltage is switch...

Page 10: ...MEA or SDI 12 transponders Custom drivers can be developed on request External sensors transponders can be powered by the data logger itself to prevent them to consume power while the data logger is asleep The excitation voltage is switched off during sleep as well OMC 042 OMC 042 Powered from a 3 6V DC SAFT LSH20 or equivalent D size lithium battery OMC 042 01 With integrated 3 x AA NiMH charger ...

Page 11: ...ith one serial port to capture measurements from ASCII MODBUS RTU NMEA or SDI 12 compatible sensors External sensors can be powered by the data logger itself to prevent them to consume power while the data logger is asleep Up to 8 mathematical channels are available to calculate meaningful engineering values derived from sensor input values e g a polynomial to calculate a flow from a stream level ...

Page 12: ...EM 7 Internal External antenna selection jumper 8 U FL connector for external antenna 9 Internal antenna 10 Connector for optional external waterproof USB connector 11 Internal USB connector 12 Processor 13 SIM 2FF SD card Holder 14 Fuse 15 3V6 power supply connector to PV or DC cover 17 RTC clock battery OMC 044 The OMC 044 is similar to the OMC 043 but with the additional feature of supporting 4...

Page 13: ...n and network settings must also match to those supplied by the SIM card provider The pin code of the SIM card must be removed prior to insertion in the data logger To prevent problems with the SIM card it can be inserted in a mobile phone or 2G 3G data modem In a Mobile phone or 2G 3G modem the 2G 3G SMS and GSM data functionality can be tested When you have obtained a 2FF SIM card you can insert...

Page 14: ...g term stability and proper operation Power on for the First time In the factory the data logger is programmed with the necessary system information This information is viewable in the menu The data logger is ready to use out of the box if the preparations are checked SIM card is inserted SD card is inserted Internal battery or mains power is connected Antenna is connected Next connect your sensor...

Page 15: ...nformation see the reference Example Let s Configure an OMC 043 for operation with the following Analog pressure transmitter 4 20mA CT2X conductivity temperature sensor INW FTP data output EMAIL data output Connect the logger to a free USB port on your computer and open with a terminal emulator the virtual COM port e g COM7 as assigned by Windows to the logger The first time Windows will ask if no...

Page 16: ... the sensors and data output General settings 0 Exit 1 System name Observator 2 Data log interval 00 10 00 3 Continuous alarm sampling Off 4 Direct data output on data alarm Off Digital alarm output port Enabled 6 Deployment date and time 2015 08 31 06 55 23 7 Daily operating time slot 24 hour 8 Time zone 0 9 Summer time daylight saving Not used Configuration setup 0 Exit 1 General settings Observ...

Page 17: ...A If you don t know those values you could determine the scaling by measuring two calibration points option 8 Those calibration points don t have to be at the sensors absolute minimum and maximum but just two different points within the range of the sensor e g a measurement at 1m water level and a measurement at 2m water level while the sensors range is 0 10m 5 If necessary option 9 can be used to...

Page 18: ...r height 2 Sensor power switch Enabled Warm up 00 00 02 3 Sample interval Data log interval 4 Port mode Port 1 4 20 mA 5 Parameter settings Analog 6 Parameter value at 4 mA 0 meter 7 Parameter value at 20 mA 10 meter 8 Determine linear conversion function 2 calibration points 9 Determine linear offset only 1 calibration point R Remove ...

Page 19: ... sensors can be connected to an RS485 bus so you need to specify its address assuming 1 in this example This sensor is a multiple parameter sensor so please specify which you want to log Attention Because this is a digital sensor it takes a little bit more time to measure than an analog sensor So don t set the sample interval of digital sensors too short 1 second is possible but probably not sec J...

Page 20: ...ectivity of your device by using the APN login test After correct configuring it should look like this Now we can setup the FTP TCP and Email output Therefore go to menu option E Email output F FTP output G TCP output H HTTP output Enter your server settings Modem settings 0 Exit 1 Provider selection 2 Network 3G 2G fallback 3 APN access point 4 APN username 5 APN password 6 APN authentication PAP...

Page 21: ...ensors in the configuration because of the monitoring of the performance of the data logger itself Most users like to keep track of the battery life for example 0 Exit 1 Name Email 2 Send interval Normal 01 00 00 Alarm Not Used 3 Send delay Not Used 4 SMTP Server smtp provider com 5 SMTP Port 25 6 User name reh6a01 7 Password 8 Originator address r beun provider com 9 Destination address your prov...

Page 22: ... D The result should be like this Internal sensors 0 Exit 1 Name Internal 2 Sample interval Data log interval 3 Battery capacity 14000 mAh 4 Battery replaced Yes 5 Rest capacity Not used 6 Rest power Not used 7 Processor temperature Processor temperature 8 Average voltage Not used 9 Max voltage Not used A Min voltage Min voltage B Average current Not used C Max current Not used D Min current Not u...

Page 23: ...erval will NOT execute unless they are used in aggregations e g a 10 minute average see chapter Aggregation channels scheduled for continuous alarm sampling or if a pending alarm is detected and you have set alarm set delay to number of samples So in most cases you could follow the default data log interval to take a sample Data logging interval This interval determines when a data value obtained ...

Page 24: ...s the data on the SD card When the sample is taken the data logger goes into sleep mode again This is repeated until the time has matched the Send interval So in this example this is 3 hours 4 When Data Send interval is reached the data logger will wake up and starts to send the previously collected data stored on the SD card to the server So in this example every 10 minutes a sample is taken and ...

Page 25: ...4 mA 0 centimeter Decimals The numeric precision of the value displayed and stored on the SD card of course not the real life precision only the numeric presentation Data log Setting which enables the storage of the parameter to the SD card When set to off it will be measured and displayed but NOT stored on the SD card Default set to ON Data transpond It s only enabled if you have installed a Radi...

Page 26: ... digital alarm output port when the selected alarm limit is passed Low High or both Alarm limits and delays Within every parameter settings menu the user can define all limits and delays to customize his alarming mode More info on these settings and the alarming mode is found in section Alarming ...

Page 27: ...em Information A read only menu section which displays all specific details about the data logger an example is given below System Information ML 315 Logger Version 2 2 Build 1 0 Exit Serial number 5024367 Hardware model ML 315 Modem type UMTS UL865 EUR IMEI number 355856050243670 Hardware edition ADS Analog Digital Serial Production date 2015 06 22 Test date 2015 06 23 RTC adjustment frequency 51...

Page 28: ...ings 2 Modem settings 3 NTP time update Not used 4 Alarm SMS Not used 5 SMS commands Not used 6 Internal sensors Internal 7 Analog sensors Water height Potmeter 8 Digital sensors Display 9 Network signal sensor Not used A Serial port Not used B Accessory port Display C Calculated channels Used D DTU connection Not used E Email output Not used F FTP output Not used G TCP output Not used H HTTP outp...

Page 29: ...g interval is long This setting introduces a second interval which must be shorter than the normal data log interval First read the basics of the alarming interval Normally the alarming mode can only be entered by awaiting the data log interval but this global setting allows the user to define a shorter interval The logger will now wake on this shorter interval but not store the data It must be en...

Page 30: ...sable the data logger from operation outside this interval This makes sense when measurements are correlating with working hours or in other specific situations E g a data logger won t alarm or log data when the temperature of the boiler is too low while no one makes use of that The logger will alarm you when this happens during a working day Time zone Time offset to meet local time zones half s a...

Page 31: ...of preference The Fallback option 3G 2G is very good in areas where both are available but not that strong Access Point Name APN Name of the access point that your provider has defined consult your provider for this setting Sometimes when authentication is enabled a username password is required else leave blank Also consult your ISP for this APN Authentication The protocol used for authentication...

Page 32: ...ually forces device to update time via NTP in order to test the feature Alarm SMS System Alarm SMS Check this option if you want to receive system alarms via SMS like Deployment start sensor timeouts sensor could be broken or TCP FTP HTTP server not available etc Data Alarm SMS Check this option if you want to receive data alarms via SMS SMS Commands ACVA SMS This feature enables the user to call ...

Page 33: ...hium battery The calculations of the rest capacity will be reset battery rest capacity 100 Rest Capacity Remaining capacity of the lithium battery In percentage of a full battery Rest power Same parameter but in mAh Attention the battery full parameters are only representative when used in lithium battery only systems When using a solar panel or external power they won t work Their readings are no...

Page 34: ...nge the battery or charge it With solar systems in the dark months this can be an issue and this can be solved with the aid of good weather Average Max Min current Same as above but for current The data send sessions are clearly recognized by the use of these parameters Operating cycle This virtual sensor measures the time that the data logger is awake performing tasks This gives also good diagnos...

Page 35: ...function into the data logger This feature will determine the same function described above but will use a physical reading instead of a manually entered figure The user will be prompted to measure 2 calibration points e g 2 different sensor heights in a water column The user must enter both real life values of the calibration measurements This feature is convenient while performing a field calibr...

Page 36: ...e rate for the digital input is very low no events are missing This is an important difference So what is the use of the sample interval in respect to digital inputs It defines the update rate of the counter value connected to that port Example Suppose a user connects a wind speed sensor anemometer to the digital input and this sensor generates a pulse with a frequency of 13 Hz So every second the...

Page 37: ...art with This value is updated when a pulse or unit depends on register mode is measured on the input so each time you consult this menu this setting will be accurate automatically Register Reset User can select if he wants the counter value to be reset at midnight or that the counter is always incrementing 32 bits Log each counter change This is only possible with low frequency sensors The event ...

Page 38: ...don t find functions like min max average Below the menu settings of an alarm input is shown Trigger delay The amount of time the data logger waits before changing to the alarm state when the input condition is true When the logger measures an alarming input condition it enters the pre alarming mode This mode will change into alarming mode when the trigger delay has finished If the alarming condit...

Page 39: ...eeds but preferably use the send interval as setting Signal bars A comprehensive presentation of the quality of the sensor the network coverage at you installation site 0 bars no reception it will not work The system will work from 1 bar and above Try to setup your external antenna for optimum reception 3 or more is a very good reception Signal dB indication bit error rate A technical presentation...

Page 40: ...witch based anemometer self powered like a pyranometer or negligible like a 20KOhm wind vane potentiometer The power draw is about reversed proportional to the sample interval a twice longer interval will draw about 50 less power Per aggregation channel you have to choose which input sensor values you want to use for aggregation Choose an aggregation period a commonly used wind speed aggregation p...

Page 41: ...unctions a o cos sin atan2 ln sqrt Syntax Within the data logger each sensed calculated parameter channel has a parameter code chosen by the user e g TEMPC for a temperature in Celsius Note codes should not contain any spaces or signs These parameter codes can be used in equations by preceding them with a colon When calculating the parameter codes will be substituted with the last recent measured ...

Page 42: ... recent measured values You could enter the equation round TEMPC 1 8 32 10 10 to convert a temperature in Celsius to Fahrenheit and round the result to one decimal Example 2 Assume we measure a river height in m parameter code LEVEL and want to convert it to a flow by using the pre determined polynomial see graph below y 0 253x3 21 675x2 359 14x 1677 5 Then the formula should be entered as follows...

Page 43: ... to radians todeg radians converts radians to degrees floor x returns the largest integer not greater than x ceil x returns the smallest integer not less than x round x rounds to the nearest integer Supported mathematical functions with multiple arguments atan2 x y return the arc tangent of x y mod x y return the reminder of x y pow x y returns x to the power of y clip x min max returns x clipped ...

Page 44: ... 10 11 returns 11 Synonym If x y return x else return y Supported comparisons with 4 arguments eq x y q p returns q if x is equal to y else return p Example eq 10 11 0 3 returns 0 Synonym If x y return y else return p lt x y q p returns q if x smaller than y else return p Example lt 1 2 3 4 returns 3 synonym if x y return q else return p le x y q p returns q if x smaller or equal than y else retur...

Page 45: ... Modbus RTU is shown Port Settings The user can select the right baud rate and Modbus Address of his sensor here The address of the sensor is very often adjustable with the aid of a configuration tool of the sensor s manufacturer So the user can changed this according to its need You can build a multi sensor network by using unique addresses RS232 sensors 0 Exit 1 Generic MODBUS RTU 2 Generic Seri...

Page 46: ... bytes needed to fill the selected data type Data Type The type of the data that is stored in the sensor the starting address See table below Datatype Size Signed Remarks WORD 2 bytes unsigned Short 2 bytes signed DWORD 4 bytes unsigned Integer 4 bytes signed Float 4 bytes IEEE754 All 4 bytes data types are also available for reversed logic byte swapping Consult your manual what data type is used ...

Page 47: ...e 0x20 is used This is the default setting A comma semi colon or tab character are commonly in use as well Start Stop character These define with which character a data sentence starts and terminates E g an NMEA sentence starts with a and terminates with a carriage return CR Output start command Sometimes a device that outputs a serial sentence doesn t output its data at regular interval but it ne...

Page 48: ...ic value e g A will be recorded as 65 Example An NMEA 0183 compliant weather station could output the wind direction and speed with the following sentence This sentence contains 6 comma separated fields WIMWV 190 0 R 11 0 N A 1B The Wind direction value is found at position 1 in the sentence and the sentence can be distinguished from other NMEA sentence by specifying MWV as the Sentence filter Gen...

Page 49: ...nsult your sensors manual After selecting the right measurement command the command is displayed in the menu so the user can check this against the sensors manual Parameters The various data values that were retrieved from the SDI 12 sensor can be stored into different parameters They behave like normal generic parameters See more info Parameters SDI12 sensor 0 Exit 1 Name SDI12 2 Port settings SD...

Page 50: ...tem via wire Send interval The send interval on which the data is send to the radio This can be another send interval than the internal modem has More on send interval see Send Interval Send delay When the user likes an time offset in respect to the send interval he can set this offset here This is practical using multiple radio s they must NOT be sending simultaneously The send interval can be th...

Page 51: ...g you can checks the signal strength by issuing the AT CSQ command or even try to send a text message with the AT SBDWT command Iridium SBD Service SBD messages are transmitted to an Iridium server GSS Gateway Short Burst Data Subsystem and you can ask your Iridium provider to pass SBD messages to an e mail address of your choosing or via directIP to an IP address domain and TCP port of your choos...

Page 52: ... is rather expensive you can choose to send only the last sampled values instead of logged values When choosing to transpond logged values be aware to select a moderate log interval to avoid high communication costs Note only parameters with the Data transpond flag enabled will be included in an SBD message Backup mode When the Backup mode is selected satellite communication will be performed only...

Page 53: ...s of setting up an alarm on the position of the device Sometimes it is important to track the position of the system and to couple an alarm to it I e with buoys this might be the case The buoy must measure on a specific location and may drift a few meters but must not drift too far To setup an alarm with the corresponding limits is very unpractical because the user has to work with the coordinates...

Page 54: ...d to the starting position of the system It automatically calculates the alarm limits for the parameters latitude and longitude Thanks to this the user can define a box of allowed movement at the office and during deployment the absolute alarm limits for latitude and longitude are calculated Also the user can define a second bigger box which corresponds with the hi hi limits of the data logger So ...

Page 55: ... data and also more power required So don t exaggerate with the picture size The pictures can be send to you by HTTP E mail FTP or TCP Pictures can be taken independent from the normal data logging interval e g once a day Interval 24 00 00 at 9h Shift with 09 00 00 0 Exit 1 Name Camera Port settings RS232 8N1 115200 Baud 3 Module power switch Enabled Warm up 00 00 02 4 Independent data log On 5 Sa...

Page 56: ...y with a resolution of 320 240 pixels The settings of the display are very simple and shown below Display settings Power down delay This is the time the data logger shuts the display down after not touched anymore With this accessory you can recall graphs or numeric actual values of all parameters It has an auto scale feature for graphing and allows the user to browse the history of the measuremen...

Page 57: ...id or external power source The RTU function can be programmed to wake up at a regular interval or on alarm e g an external digital interrupt At wake up the DTU switches on the power to the serial device connects to the TCP server and forms a transparent serial data channel between serial device and host TCP server The transparent channel will be broken after expiration of a certain timeout or whe...

Page 58: ...t of the host server Client ID ID of the system this DTU is connected to In case of an legacy system without addressing this can be used Termination ID This is a user defined string which can optionally be used When the host sends this string to the DTU it will break the connection and continue often go into sleep mode The use of this is optional Also the host can disconnect the TCP session and th...

Page 59: ...allow traffic on this port except for their own server Therefore a problem arises So in order to solve that many providers open a second port for SMTP And our data logger is supporting that So you can use this anytime Originator address This is the email address of your system Please note that some ISP s block strange addresses so make sure to use a serious address or make sure that it is not bloc...

Page 60: ...wiki File_Transfer_Protocol Directory The relative path to the destination on your server Data format This defines the data format of the file s content This can be our native TXT format JSON or a CSV comma separated value format which can easily be picked up by third party applications like Microsoft Excel We prefer our native format as it can contain data as well is diagnostic info FTP settings ...

Page 61: ...rted Implementing Digest MD5 authentication is on a to do list Data format This defines the data format of the file to post This can be our native TXT format CSV comma separated value format or our JSON format which can easily be picked up by server side scripting of an HTTP server Depending on the data format the following Content Type HTTP header will be added to the post text plain Our native T...

Page 62: ...received from the server Digest is more secure but will consume about 1 second more precious power time per transfer Note To spy a basic password a hacker has to breach the GPRS 3G communication or intrude the local network where the server is running Data format This defines the data format of the file s content This can be our native TXT format JSON or a CSV comma separated value format which ca...

Page 63: ...overview of used measurements and its sample rates etc See example below Parameter list Code Name Unit Dec Min Max PM Potmeter 0 1 99 RPT R PT1000 Ohm 3 TPT T PT1000 C 3 AIN Analog meter 3 0 100 MINVi Min voltage V 2 OCi Operating cycle sec 2 PTi Processor temperature C 1 CNT Counter unit 3 0 Exit Measurement list Code Sample interval Alarm interval Data log Data transpond PM 00 00 01 Not used Off...

Page 64: ...e example below Alarm list Code Alarm SMS Alarm log Alarm output Alarm samples PM Disabled Off Disabled RPT Disabled Off Disabled TPT Disabled Off Disabled AIN Disabled On On 0 MINVi Disabled Off Disabled OCi Disabled Off Disabled PTi Disabled Off Disabled CNT Disabled Off Disabled 0 Exit Alarm limits Code Low low Low High High high Hysteresis PM RPT TPT AIN N A 20 50 N A 0 5 MINVi OCi PTi CNT 0 E...

Page 65: ...l known voltage current source Below a screenshot of this test is shown The internal reference must always be 1 2 Volts 0 1 For using this feature in the field just disconnect your sensor and attach your calibrator and check the value Digital input test This test allows the user to test the proper operation of the digital inputs Below a screenshot is shown The pulses generated during this test wil...

Page 66: ...ture allows the user to communicate with the sensor directly It offers a transparent connection from the USB terminal screen to the sensor Baud rate settings can be selected to match the connected sensor During the session the sensor power switch of the data logger is enabled to supply the sensor So a very convenient way of testing troubleshooting configuring your sensor is possible Also comport r...

Page 67: ... logger When you like to retrieve a configuration file from the data logger select the option configuration download and use Y modem receive file option Navigate to your path of preference and the configuration file will be downloaded to your computer This file is a non readable binary file which contains all settings of your data logger You can store this for backup reasons or as a template to co...

Page 68: ... upgrade This is a seldom used feature but it is important in some rare occasions For more info see Modem Firmware Upgrade Bootloader Menu This menu is for expert use only It allows the user to jump to the bootloader where the firmware is NOT loaded yet Normally the user does NOT use this menu or its options Only when the logger has severe problems this menu can help it is this like the old rescue...

Page 69: ...se of RS232 and RS485 So you cannot connect a SDI 12 sensor to a RS232 or RS485 port it won t work The use of convertors between RS232 485 and SDI 12 is discouraged because of the high pricing of the convertors and the bad performance see note SDI 12 Wiring The SDI 12 electrical interface uses the SDI 12 bus to transmit serial data between SDI 12 data recorders and sensors The SDI 12 bus is the ca...

Page 70: ...a widely spread interface standard which uses 3 wires minimum for data communication It is a so called asymmetric interface that uses one wire for TX one for RX and one for ground It is called asymmetrical because it uses only one wire per signal Therefore it s susceptible for interference and hence the maximum cable length is limited to 15meters Please keep in mind these limitation when you desig...

Page 71: ...er has one RS485 port which is capable of driving multiple sensors maximum amount of sensors depends on specs from the manufacturer of the sensor a practical figure is 10 The maximum amount of slaves defined by EIA RS485 is 32 For the exact number of sensors you can connect to your OMC 042 see chapter Firmware Driver limitations We recommend using twisted pair cable to connect to the sensors ...

Page 72: ...sibility offers a flexible way to expand the range of the instrument this is NOT covered in this manual and the user may not seek for support from Observator Instruments on this topic Analog Differential Inputs OMC 042 only The OMC 042 Data logger has besides the four 12 bits analog current inputs also two additional Differential 16 bits voltage inputs These inputs are very sensitive and particula...

Page 73: ...utput Voltage other than 0 Volts To enable the circuit the bridge has to be powered by a very stable reverence Voltage often called Excitation Voltage The OMC 042 has an Excitation output for this purpose Excitation Output The OMC 042 has an Excitation output for powering load cells or other devices It is a single output with a fixed precision voltage output This Excitation output is driven by the...

Page 74: ...nput 5 this is very accurate it will be 0 05 For an application that requires an even higher accuracy the user can and should do a user overall calibration Overall Calibration This type of calibration is offered to the user to get the most accurate readings possible This type of calibration is a two point s calibration How it works The user can enter 2 pre defined data values into the OMC 042 This...

Page 75: ...connected to the fixed resistor and the middle terminal is connected to a slider So when a potmeter is turned the resistance between the middle terminal and one of the outer terminals is changing with the angle of the potmeter Very often potentiometers are used to regulate a voltage from 0 to 100 of the input voltage In the next figure this well know circuit is drawn The output voltage is adjustab...

Page 76: ...round So when NO signal is connected the input will be logical low This type of inputs is very convenient for use with active output systems or PNP outputs Electrical specifications Digital inputs Below table give an overview of the Electrical specifications of the Digital inputs Vil is logical low level Vih is logical high level Pull up down resistors are 40 k typical lect Parameter Min Max Vil 0...

Page 77: ...eached when the data logger encounters a value which is higher than the high high Limit this is the 2nd and most urgent state of alarming This type of alarming is used for very rare and critical conditions often called STOP level Alarming principal of operation When a data logger is running and a measurement is out of boundary the data logger will immediately switch over the alarm sample interval ...

Page 78: ...resis is only used for switching back to the normal mode The amount of hysteresis has an effect on the sensibility of the alarming It is strongly advised to use a certain amount of hysteresis to prevent from multiple alarming warnings The amount of hysteresis is determined by experience and information from the sensor ...

Page 79: ...vel due to vaporization while there is no demand for water or why alarm when water is just over a high limit due to precipitation while there is no forced supply To avoid unnecessary level alarms you could define a calculated channel with the following equation ALARMLEVEL gt FLOWIN 0 LEVEL gt FLOWOUT 0 LEVEL LEVELOK Where gt a b c d is a function that returns the value c when a b otherwise it retu...

Page 80: ...ption Maintenance Follow instructions from the menu Use Y Modem protocol to send the new firmware to the data logger Don t remove the USB nor power from the data logger When these steps are completed the new firmware is active We recommend the use of the USB connection over the wireless function This is because of possible drop outs in communication When a firmware upgrade procedure is interrupted...

Page 81: ...s used in the logger This is often used to re configure a logger remotely or to monitor actual values In most cases normal GPRS communication is sufficient for the operation of the data logger The modem inside the OMC 043 is capable of 900MHz 2100Mhz 3G communication as used in the EMEA and APAC regions Modem Firmware Upgrade The modem inside the data logger is equipped with the latest firmware ve...

Page 82: ...meter Name 4 Parameter Unit 5 Parameter Code The abbreviation of the full parameter name it may be up to 7 characters long Parameter Name The name of the logged parameter it may be up to 31 characters long Parameter Unit The unit representing the physical dimensions of the measurement it may be up to 15 characters long All characters are allowed except this is reserved for a separator D Records Mo...

Page 83: ...lue of the measurement together with a optional data modifier forms the measurement Example Data record s D 110928030200 RCi 95 8 PTi 50 1 Vi 3 6 AVGCi 71 OCi 0 25 MAXCi 71 D 110928030300 RCi 95 8 PTi 49 3 Vi 3 6 AVGCi 71 OCi 0 25 MAXCi 72 D 110928030400 RCi 95 8 PTi 49 5 Vi 3 6 AVGCi 72 OCi 0 25 MAXCi 72 D 110928030500 RCi 95 8 PTi 49 1 Vi 3 6 AVGCi 72 OCi 0 25 MAXCi 54 D 110928030600 RCi 95 8 PT...

Page 84: ...s 3 Message code 4 Optional supplemental code or text 5 Optional explanatory text See Appendix System messages for a list of possible messages and their meanings Example S records Data Modifiers Normally a data value presented in D records is recorded without a Data Modifiers but in case of a malfunction or rare circumstances a Data Modifier is added to the data value See table below Data Modifier...

Page 85: ...efined unit e g C channels code PTi name Processor Temperature unit C code CHx name Channel x unit Unit x code SB name Signal quality unit bars The channels array is for convenience terminated by an empty object 3 The data object is an array of objects listing timestamped events a timestamped object always starts with a timestamp variable ts followed by one or more variables where a variable can b...

Page 86: ...uch rare cases consult your local Observator supplier for a calculation of battery life before exploiting care logger Analog sensors The OMC 042 is provided with 4 factory calibrated analog inputs with 12 bit ADC resolution Analog input 5 and 6 are factory pre calibrated amplified differential inputs with 16 bit ADC resolution Input Range Accuracy Impedance 1 4 20mA 0 1 150 Ohm 2 4 20mA 0 1 150 Oh...

Page 87: ...data logger is allowed to sleep most of the time and only capture the events of the digital interrupt e g the tipping bucket of a rain gauge In the situation where only one digital sensor is used the battery is probably going to last much longer than any other measurement For safety reasons a user can include some internal measurements in the configuration to allow monitoring of the performance of...

Page 88: ...eep mode When the battery is replaced this value is NOT lost and is resuming after replacement of the battery Quantity Quantity is the difference between the actual counter value and the previous counter value So when your data log interval is set to 10 minutes this parameter shows you the amount of pulses per 10 minutes Every log interval this count is reset to zero Important So when you use Actu...

Page 89: ...tion of the device When the device is going into sleep mode a fixed value is used to calculate the power consumption Both are calculated and offer a fairly accurate measurement of the power consumption Unfortunately the behaviors of batteries are in practice much more complicated than the calculation made inside the data logger So the capacity written on the back of the battery is only a typical v...

Page 90: ...ff input 6 0 80mV Positive terminal analog input 6 8 diff input 6 0 80mV Negative terminal analog input 6 X4 1 Switched module power output 5V Terminal to switch on external modules a o display 2 SDI 12 0 5V Terminal to connect SDI 12 sensors 3 Switched power output 12V 100mA Terminal to supply power to sensors 4 Switched stable excitation 5V 80mA Terminal to supply a stable power to bridge sensor...

Page 91: ... 1 Digital input 1 0 5V Positive terminal digital input 1 or wake up line 2 Digital input 2 0 5V Positive terminal digital input 2 3 Digital input 3 0 5V Positive terminal digital input 3 4 GND Ground X4 1 Switched power output 12V 100mA Terminal to supply power to sensors 2 Alarm output Open collector max 100mA sink current 3 GND Ground X5 1 5V switched power output To power an accessory e g TFT ...

Page 92: ...th a ground signal These signals are ESD protected by the driver circuit The signal levels are according to the TIA EIA 485 Standard Power Switch This is an output to drive one or more sensors It holds a level of 12 Volts and is capable of driving up to 100 mA VBAT This is the main power supply input for the board The level is 3 6 Volts Note This signal is NOT the same as the internal 3 6 volts le...

Page 93: ...surface below the antenna others dipole antennas do not Make sure that all connectors on the antenna and antenna cable are tightened and free of moisture Make sure the antenna is in vertical position as the GSM and 2G 3G radio signals are vertically polarize the antenna should be vertical positioned for maximum performance Do not place the antenna near metal surfaces or structures Be aware that va...

Page 94: ...a high precision measurement the analog interface may be re calibrated after that period High temperature deviations and harsh environment are factors that needed to be considered Please contact your local supplier for more information on recalibration needs and support The real time clock is also calibrated during the manufacturing process and has very good long life stability see spec sheet Also...

Page 95: ... of the battery power The mains power supply is protected by a 4AT fuse type TR5 ESD The data logger is equipped with an ESD Electronic Static Discharge protection on all outside world leads i e comports and analog inputs etc Though it is designed to withstand a certain amount of electrical discharge human body model it is strongly advised to take precautions while operating or servicing the data ...

Page 96: ...ces EU directive 2002 95 EC which means in popular terms that the product is lead free When the data logger is taken out of service dispose the data logger in accordance to the local regulations at the time the product is disposed Regulations for disposal of batteries may be different Remove the batteries and dispose them in accordance to the local regulations for batteries ...

Page 97: ...er Storage Humidity 95 Non condensing Temp 10 30 C Transport Humidity 95 Non condensing Temp 10 30 C If the data logger is delivered in its standard protecting enclosure it is strongly recommended to use this case for all transportation until the final location of operation This enclosure is especially designed to protect the data logger from being damaged ...

Page 98: ...SB 2 0 full speed interface Sample Frequency max 4 Hz Datalog Frequency max 4 Hz Rohs Complient Yes Analog Inputs Number of Single Ended Channels 4 Resolution 12 bits Input type 0 20 mA Channel 1 to 4 0 10 V MLx15 xxx only Number of Differential Channels 2 OMC_042 only Resolution 16 bits Input type Voltage 0 2000 mV 8 different ranges Smallest detectable step 1 uV Memory Card Type micro SD Capacit...

Page 99: ...e PT1000 with the wires cut to installation length at an accurately determined temperature preferably in a water of 0 C Calculate the resistance at 0 C R0 by subtracting 3 84 O per C above 0 C Use a high impedance potentiometer e g 1MO to perform a two point user calibration on the potentiometer input of the OMC 043 For the first calibration point turn the potentiometer to its lowest resistance an...

Page 100: ...a reference resistor of about 1k and connect it between the potentiometer Vref 3 3V at connector X1 pin 8 and the potentiometer input X1 7 b With an accurate multi meter measure the current between potentiometer input X1 7 and GND X1 6 c Calculate the total reference resistance Rref by dividing 3 3V Vref by the measured current 3 connect a PT1000 between the potentiometer input X1 7 and GND X1 6 4...

Page 101: ...OMC 042 043 044 Data loggers Users manual page 101 Example ...

Page 102: ...totally out of date it designates a RTC problem There should be NO errors on this startup If there are errors contact your local Observator Instruments dealer A screen dump of the startup messages will help to solve the problem An example of a defective data logger is given below This data logger has its micro SD card not installed You can clearly notify the problem by looking at the startup messa...

Page 103: ...while initializing Modem No response from Modem or no SIM or SIM not detected or PIN on SIM WDT NETWORK_REG Watchdog timeout while trying to register on a network No response or temporarily no network coverage or SIM subscription failure inactive invalid blocked or black listed WDT APN_OPEN Watchdog timeout while trying to find an internet access point No response or APN access point name wrong WD...

Page 104: ...r occurred Unknown SMS_SEND_ERR An error occurred while sending SMS See the Modem ERR WDT message before for more details SMS_SEND_OK Sending of the SMS was successful SMS_RECV_ACVA Phone number An ACVA SMS was received SMS_RECV_ERR Phone number An invalid SMS was received CNT_RESET digital sensor name Shows the reset of the pulse counter When reset at midnight option is on or after manual change ...

Page 105: ...OMC 042 043 044 Data loggers Users manual page 105 ...

Page 106: ...OMC 042 043 044 Data loggers Users manual page 106 ...

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