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SCT-20 Series Signal Conditioning Transmitter/Indicator Technical Manual March 2, 2022 PN 131128 Rev H...
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All information contained within this publication is, to the best of our knowledge, complete and accurate at the time of publication. Rice Lake Weighing Systems reserves the right to make changes to the technology, features, specifications and design of the equipment without notice.
Keypad Or Display Locking ..............27 Technical training seminars are available through Rice Lake Weighing Systems.
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FCC Compliance..................63 Rice Lake continually offers web-based video training on a growing selection of product-related topics at no cost.
Do not operate or work on this equipment unless this manual has been read and all instructions are understood. Failure to follow the instructions or heed the warnings could result in injury or death. Contact any Rice Lake Weighing Systems dealer for replacement manuals.
IMPORTANT When the SCT-20 is installed inside of the electrical panel, it is recommended that the units be installed vertically to a horizontal DIN rail. This minimizes heat buildup from multiple units being stacked and also enables optimal ventilation through the unit. If possible, it is recommended that the unit be installed towards the bottom of a panel to avoid the warmest parts of the panel.
Make sure it reads between 0 and 0.5 mV. • Apply load to the load cell and make sure that there is a signal increment. If one of the above conditions is not met, please contact Rice Lake Weighing Systems Customer Support for IMPORTANT assistance.
SCT-20 Series Connectivity Analog Output (Current and Voltage) DC Power Other Options Supplier DeviceNet (12-24 Volt) PROFIBUS PROFINET Ethernet Junction Box Serial Port RS-485 RS-232 MAX 8 Load Cells Modbus RTU In Parallel 3 Relay Outputs 2 Digital Inputs PLC or Field Signals...
SCT-20 Series LED Functions Figure 1-4. Display Main Function Secondary Function * Net weight LED None Zero LED (deviation from zero not more than +/- 0.25 divisions) LED lit: output 3 closed Stability LED LED lit: output 2 closed Unit of measure: kg...
SCT-20 Series 1.11 Instrument Commissioning 1. Plug power cord into an outlet to power on the indicator. The display shows in sequence: • followed by the software code () • followed by the software version () • followed by the hardware code () •...
SCT-20 Series 2.1.2 Theoretical Calibration This function allows load cell rated values to be set. To perform the theoretical calibration set , and in sequence. See Figure 2-2 on page 1. Press and hold , then press . is displayed.
SCT-20 Series 2.1.7 Setting Units of Measure 1. Press and hold , then press . is displayed. 2. Press , is displayed. 3. Press until is displayed. Press 4. Press until desired unit is displayed. Press 5. Press twice to exit set-up menu.
SCT-20 Series Zero Parameters 1. Press and hold , then press . is displayed. 2. Press until is displayed. Press 3. Press until desired parameter is displayed. See Table 2-6 4. Press . The currently programmed value is displayed.
SCT-20 Series 2.4.1 RS-485 Serial Communication 0 VDC RS485 - RS485 + 0 VDC RS485 - RS485 + If the device is labeled A and B Connect A to RS485- Connect B to RS485+ 0 VDC RS485 - RS485 +...
SCT-20 Series Parameter Options Description Full scale analog output correction: if necessary adjust the analog output, allowing the PLC to indicate the value set in the parameter. Example: for a 4-20 mA output with the analog set to full scale and the PLC or tester reads 19.9 mA, set the parameter to 20.1 to obtain 20.0 on the PLC or tester.
NOdbUS 4800 ASCII 9600 EUEn 19200 HdrI P 38400 HdrI Pn 115200 Figure 2-8. SCT-20 TCP/IP Menu Structure Parameter Options Description Set IP address in the EtherNet/IP™ network. ** * Set Subnet mask. ** * * Set the Gateway address.
SCT-20 Series 2.10 Outputs And Inputs Configuration DeviceNet Options Analog Options Profibus Options Ethernet Options Figure 2-9. Outputs and Inputs Menu Structure Parameter Options Description OUt 1 OPEn Normally Open: the relay is de-energized and the contact is open when the weight is lower than the programmed OUt 2 setpoint value;...
SCT-20 Series 2.12 Setpoints Programming 1. Press to enter setpoints and hysteresis settings. 2. Press until desired setpoint or hysteresis parameter is displayed. Press 3. Press until desired value is displayed. Press 4. Press to exit setpoints and hysteresis settings.
Press to quit the program without introducing any changes and without deleting any of the set variables. If necessary, a manual for the newly set program can be requested it from Rice Lake Weighing Systems Technical Note Support. 2.13.7 Keypad Or Display Locking 1.
SCT-20 Series Operation Semi-automatic Tare (Net/Gross) The semi-automatic tare value is lost upon instrument power-off. Note The semi-automatic tare operation is not available if the gross weight is zero. 1. To capture tare and weigh in net mode (Semi-Automatic Tare), close the Net/Gross input or press for three seconds.
The load cell is a 4-wire and there are no jumpers between EX- and REF- and between EX+ and REF+. The weight display exceeds 110% of the full scale. Internal instrument converter failure. Check load cell connections and, if necessary, contact Rice Lake Weighing Systems Technical Support.
The SCT20-DN works as a source in a DeviceNet network. Load the included EDS file (DeviceNet_20.eds) in the DeviceNet primary’s development instrument. The data exchanged by SCT20-DN are: Outgoing Data from SCT-20 DeviceNet (Read) Addresses Gross Weight [4 bytes] 0x0000-0x0003...
SCT-20 Series PROFIBUS • The SCT20-PB works as a PROFIBUS DP V0 source in a PROFIBUS-DP network. • Load the included .gsd file (Profibus_20.gsd) attached to the instrument in the development system of the PROFIBUS primary. • The available modules are: •...
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SCT-20 Series Digital Outputs Command It allows control to the outputs status in See Section 2.10 on page Bit No. Description Bit No. Description Bit 0 OUTPUT 1 status Bit 8 — Bit 1 OUTPUT 2 status Bit 9 —...
SCT-20 Series SCT-20 EtherNet/IP™ The SCT20-IP works as a device in a EtherNet/IP network. 3.8.1 Instrument Setup 1. Press and hold . displays. 2. Press until displays. Press 3. Press to navigate through menu. • : select the reading/writing of the byte in LITTLE-ENDIAN or BIG-ENDIAN mode –...
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SCT-20 Series Generic EtherNet/IP Module Setup The configuration used when setting up a device with the generic module file. Figure 3-2. Dual Port – Generic EtherNet/IP Module Setup Output Data from SCT-20 EtherNet/IP (Read) Addresses Type Header Information [4 bytes]...
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Operation Internal Status When the internal status is not 0 there is an internal error, so data from SCT-20 EtherNet/IP are not reliable. When the internal status is 0 data from SCT-20 EtherNet/IP are reliable. Header Information The header information value must be a 1, if it is a 0 then the SCT-20 needs to be replaced.
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SCT-20 Series Digital Outputs Command It allows control to the outputs status in mode. See Section 2.10 on page 24 Bit No. Description Bit No. Description Bit 0 OUTPUT status Bit 8 — Bit 1 OUTPUT 2 status Bit 9 —...
Press Enter to confirm. 7. Press 1 Chann to change the serial baud rate of the Ethernet Module to match the baud rate set in SCT-20 TCP/IP Protocol Selection (default 9600). Do not change any other parameters. Press Enter to confirm.
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To connect to the SCT-20 TCP/IP using a socket (for example Winsock), the port to use is 10001. To connect to SCT-20 TCP/IP via Ethernet TCP/IP through a serial virtual port (virtual COM port of a PC) perform the following steps.
SCT-20 Series 3.10.2 Set IP Address with Lantronix Software To configure IP address of SCT-20 TCP/IP, the Lantronix DeviceInstaller must be installed on a Windows PC. 1. Connect the PC and SCT-20 TCP/IP through a LAN, point-to-point or with hub/switch.
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SCT-20 Series Analog Output Setting (Analog Models Only) Write the weight in the registers 40045 (Weight value corresponding to the Full Scale of analog output H) and 40046 (Weight value corresponding to the Full Scale of analog output L), or write the weight in the registers 40043 (Weight value corresponding to the ZERO of the analog output H) and 40044 (Weight value corresponding to the ZERO of the analog output L).
SCT-20 Series 3.12 ASCII Bidirectional Protocol All the sample commands use address 1. If a different address is used it will need a different Check-Sum calculated. Note The instrument replies to the requests sent from a PC/PLC. Using the parameter, it is possible to set a delay time for the instrument before it transmits a response. See Section 2.4...
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SCT-20 Series Reading Of Decimals And Number Of Divisions The PC transmits: $aaDckckCR$01D45CR Possible instrument responses: • Correct reception: &aaxy\ckckCR Response Value Definition number of decimals division value The y field acquires the following values: for division value = 1...
SCT-20 Series Check-Sum Calculation The two ASCII control characters (ckck) are the representation of a hexadecimal digit in ASCII characters. The check digit is calculated by performing the operation XOR (exclusive or) 8-bit ASCII codes of the only part of the underlined string.
SCT-20 Series 3.15 Interface to Remote Display Remote Display (Laser Light) 1. Press and hold , then press . is displayed. 2. Press until is displayed. 3. Press . is displayed. 4. Press . is displayed.
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SCT-20 Series The instrument will respond with the string: H01 h03 h08 h00 h00 hF hA0 h00 h00 h0B hB8 h12 h73 Query Field Name Response Field Name Instrument Address Instrument Address Function Function Instrument Address Instrument Address Function Function...
SCT-20 Series Compliance DECLARATIONOF CONFORMITY SCT-10, SCT-20, SCT-30, SCT-40 2014/35/EU low voltage EN 61010-1:2010 for 230/115 VAC type 2014/30/EU EMC EN 55011:2016+A1+A11:2020 EN 61000-6-2:2019 EN 61000-6-4:2019 EN 61000-4-2:2009 EN 61000-4-3:2006+A2:2010 EN 61000-4-4:2012 EN 61000-4-5:2014+A1:2017 EN 61000-4-6:2014 2011/65/EU RoHS EN 50581:2012...
SCT-20 Series Specifications Power DC Max Sensitivity of ±7 mV/V Usable Load Cells Power Supply and 12/24 VDC ± 10%; 5W Consumption (VDC) Max Conversions 300/second Operator Interface per second Display STN backlight transmissive LCD 128 x 64 pixel resolution Display Range ±999999...
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