5020 Modbus Translator. User s Guide

Transcription

1 Siemens Energy, Inc. Oil & Gas Solutions Telge Road Houston, Texas USA Document No. SEI-OG-DLS-004 Page 1 of 10 Siemens AG 2011

2 Table of Contents 1 OVERVIEW INSTALLATION OPERATION SCADA CONFIGURATION TROUBLESHOOTING SPECIFICATIONS CONTACT INFORMATION Document No. SEI-OG-DLS-004 Page 2 of 10 Siemens AG 2011

3 1 OVERVIEW The was designed to convert ASCII protocol, from the Siemens Model 1000 digital level sensor, to Modbus RTU protocol. The Translator wires in between the SCADA unit and the sensors (through the 1010 Barrier board, as shown in Figure 6.1). The searches for sensors connected to it at 9600 N81 baud rate (up to 16 sensors). This means it configures itself. The Modbus data can be in 16 bit unsigned format or 32 bit floating point format. 2 INSTALLATION Do not apply power until all connections are made. Incoming power is connected to the SCADA side of the Translator. The sensor side is fused with a resettable one ampere fuse. The transmit lines (TX+ TX-) from the SCADA unit connect to the receive lines (RX+ RX-) on the Modbus Translator. TX+ connects to RX+. TX- connects to RX-. The receive lines of the SCADA unit connect to the transmit lines on the Modbus Translator. The sensors connect in the same manner, transmit to receive and receive to transmit. 3 OPERATION When power is first applied to the Modbus Translator the indicator light will turn orange for five (5) seconds (See Table 3.1). This allows the sensors to initialize. Then the indicator light will turn red indicating that the Translator is searching for sensors. The scan starts at unit 01 at 9600 N81. This is repeated through unit 16. Any sensors responding without errors (CRC errors, framing errors, data over run errors, or parity errors) are stored in memory. When the scan is done the indicator light will turn green indicating it is ready to receive data request from the SCADA unit. When the Modbus Translator is requesting sensor data the indicator light will turn red indicating communication activity. The number of sensors configured in the Translator can be read at holding register (address 3986). To add or remove sensors initiate a reconfiguration scan by pressing the rescan push button on the side of the Translator. The indicator light will turn orange for five (5) seconds, and then the rescan will start. Table 3.1 Indicator Light Status Light Color Orange Red Green Meaning 5 Second delay before scanning for sensors The Translator is communicating with sensors The Translator is ready to receive SCADA unit data requests Document No. SEI-OG-DLS-004 Page 3 of 10 Siemens AG 2011

4 4 SCADA CONFIGURATION The Modbus Translator to SCADA unit baud rate is at 9600 N81. There is no flow control. The receive time out must be set higher than 3 seconds. Write functions are given in Table4.1. The read function (03) is referenced in Table 4.2. A complete register map is provided in Table 4.3. The Modbus status codes are provided in Table 4.4. The sensor error codes are referenced in Table 4.5. Registers are unsigned integer 16 bit (or 32 bit floating point IEEE for level and temperature only). To get the address, subtract from the registers. Table 4.1 Modbus Write Registers Description Register Address No. Notes Registers Assign Translator unit number Default value is 1 Set Translator to 16/32 bit mode Default setting is 16 bit mode. Writing a value of 1008 will set the 32 bit floating point (IEEE) mode. Writing a value of 1007 will set the 16 bit unsigned mode. Warning: 32 bit mode sends back one more register for each level. Do not set to 32 bit mode if your SCADA system can not read floating point numbers. In 32 bit mode, if a read for multiple sensors is performed, the translator can only send back data from 14 sensors in a single read. This is due to the extra registers being sent back in 32 bit mode only (Modbus protocol rules limit this). Table 4.2 Modbus Read Holding Registers Function 03 Description Register Address No. Notes Registers Read number of configured sensors Reserved Read Translator unit number Default value is 1. A wildcard access can be used if the unit number is unknown by using 30 as the unit number. Read Translator version Beginning of sensor data Each sensor contains one block of six registers. Individual registers can be polled from each block by addressing the appropriate holding register for a sensor. Multiple sensors can be read with number of registers to read set at multiples of 6. The maximum is 96 (16 sensors X 6). In 32 bit mode the maximum is 83 due to Modbus protocol limits. Refer to the register map in Table 4 for a complete list of the sensor data Document No. SEI-OG-DLS-004 Page 4 of 10 Siemens AG 2011

5 Table 4.3 Sensor Register Map Model 1000 Digital Level Sensor Level Sensor Address U01 U02 U03 U04 Description Register Address Register Address Register Address Register Address Unit number Float 1 (top float) Float 2 (bottom float) Temperature Status register Sensor error codes Model 1000 Digital Level Sensor Level Sensor Address U05 U06 U07 U08 Description Register Address Register Address Register Address Register Address Unit number Float 1 (top float) Float 2 (bottom float) Temperature Status register Sensor error codes Model 1000 Digital Level Sensor Level Sensor Address U09 U10 U11 U12 Description Register Address Register Address Register Address Register Address Unit number Float 1 (top float) Float 2 (bottom float) Temperature Status register Sensor error codes Model 1000 Digital Level Sensor Level Sensor Address U13 U14 U15 U16 Description Register Address Register Address Register Address Register Address Unit number Float 1 (top float) Float 2 (bottom float) Temperature Status register Sensor error codes Description Notes to Table 4 Unit number Level Sensor Unit Address Float 1 (top float) Top float for level sensor. Implied decimal place at second digit (16 bit) Float 2 (bottom float) Bottom float for level sensor. Implied decimal place at second digit (16 bit) Temperature Fluid Temperature for level sensor (located 12 inchs from bottom of sensor) Status register Contains status of the data exchange for level sensor. (See Table 5) Sensor error codes Sensor error codes for level sensor (See Table 6) Document No. SEI-OG-DLS-004 Page 5 of 10 Siemens AG 2011

6 Table 4.4 Modbus Unit Status Codes Status Code Indication 1 Communication error with sensor (Parity, data over run, or framing error). 2 Communication error with sensor (CRC error). 4 Sensor time-out Error (Sensor didn't reply). 8 Sensor returned error code in sensor error holding register Table 4.5 Sensor Error Codes Error Code Indication 0 No Errors 1 Can't resolve level reading or no float is detected 2 One float is out of range on a two float sensor 4 Too many groups 8 Not used 16 Transmit to slave processor for level failed 32 Transmit to slave processor for temperature failed 64 Receive of level from slave processor failed 128 Receive of temperature from slave processor failed Note for advanced users Writing 1007 at register address 107 will set the device registers that hold top float, bottom float and temperature to 16 bits unsigned integer. Writing 1008 will set the device registers that hold top float, bottom float and temperature to 32 bits floating point format. Document No. SEI-OG-DLS-004 Page 6 of 10 Siemens AG 2011

7 5 TROUBLESHOOTING This section provides guidance in correcting problems which may be encountered during installation and operation. Refer to Table 5.1 for possible solutions when errors occur. Table 5.1 Solutions to Sensor Error Codes Problem SCADA unit time out Translator indicates zero sensors SCADA unit has a receive timeout, but Increase the SCADA unit receive time out. data does not clear in registers(i.e., old data is still in data registers) Indicator light is not green, orange, or red SCADA unit indicates a CRC error Possible Solution Increase the SCADA unit receive time out Check the connections to the sensors. Check the voltage on the sensor side of the Translator. The sensors require a minimum of 8 volts at the sensor. If the voltage is below this and the voltage on the SCADA side is higher then the 1 ampere fuse maybe overloaded. Disconnect power from the SCADA side of the Translator and look for a short, or a reason for over load on the sensor side. If all connections and voltages appear to be correct, then try swapping the transmit and receive lines to the sensors, and rescan for sensors. Increase the SCADA unit receive time out Check for correct voltage on the SCADA side of the Translator. The minimum voltage for the Translator is 9 volts Make sure the RX+ and TX+ are connected together. Not RX+ to TX-. Also this can be caused by the Translator being set to 32 bit mode when trying to read 16 bit data. If you are reading 16 bit data and get CRC errors try writing the data 1007 at register (address 107). This will set the Translator back to 16 bit unsigned mode. Status code 1 (communications error) Make sure that the sensor is configured for 9600 baud and no parity. Check the wiring of the sensor to the Translator. Make sure that the RX+ and TX+ are connected together. Do not connect RX+ to TX-. Make sure that the communication lines are not shorted together. Document No. SEI-OG-DLS-004 Page 7 of 10 Siemens AG 2011

8 Problem Status code 2 (communications error-crc) Status code 3 (time-out error) Status code 8 (register error) Possible Solution Make sure that the RX+ and TX+, and RX- and TXare connected together. Do not connect RX+ to TX-. Make sure that the communication lines are not shorted together. A configured sensor in the Translator has been disconnected, or failed to respond. Check for broken wires. If this sensor has been removed then rescan for sensors. Measure the voltage at the sensor. There should be at least 8 volts at the sensor fuse board Amy value other than 1 or 2 means the sensor need to be retuned for repair. 6 SPECIFICATIONS Power requirements Power consumption Power limit 17VDC maximum. 9VDC minimum (sensors require 8 volts minimum at the sensor). 18mA in idle mode (LED green), 30mA maximum (LED orange). 1 Ampere maximum. This is controlled by a resettable fuse Operating temperature range -40 C to 60 C Document No. SEI-OG-DLS-004 Page 8 of 10 Siemens AG 2011

9 Figure 6.1 Modbus Translator Arrangement Document No. SEI-OG-DLS-004 Page 9 of 10 Siemens AG 2011

10 7 CONTACT INFORMATION For further information or for assistance, please contact: Siemens Energy, Inc. Oil & Gas Solutions Telge Road Houston, TX Phone: +1 (888) or +1 (281) Web site: Document No. SEI-OG-DLS-004 Page 10 of 10 Siemens AG 2011