OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. • Field Interface for 2 or 4-wire transmitters • 10-30Vdc supply suits battery operation • Provides 24Vdc power to 2 wire transmitters • Includes 10kA Surge Protection. • Includes Signal Isolation. • Includes optional 250 ohm termination. • Very low power suits battery applications FEATURES • Fully surge protected inputs Wide operating temperature range DIN Rail or surface mountable Narrow 22.5mm module width No Field Calibration necessary OVERVIEW The OMNITERM LZI and LZD are current loop interface modules designed to interface field mounted transmitters in remote applications where signal isolation and surge protection is required Applications include interfacing for RTU’s, PLC’s etc. The LZI is a single channel device with additional flexibility and support for both 2-wire and 4-wire 4-20mA transmitters. The LZD is a dual channel device for increased packing density, suitable for multiple 2wire transmitters. The Omniterm LZI and LZD both include the following features: • A fully specified 10kA surge arrestor to prevent electrical surges induced on the field wiring from damaging sensitive equipment in the panel 1500Vac isolation from input to output so that ground loops cannot occur, that might otherwise affect instrument accuracy. A stable 24Vdc field power supply to power two-wire transmitters from lower voltage sources such as 12V battery systems without compromising available loop voltage or loop resistance. A precision 250 ohm resistor allowing 4-20mA to be converted conveniently into 1-5V signals for RTU’s and PLC’s. Combining the surge arrestor, isolator and 250 ohm termination into a single module, saves significant cost, engineering time and panel space in monitoring applications. Reliability figures in accordance with IEC61508 (SIL1) are available to allow inclusion of these devices in safety systems. These modules utilise advanced electronic techniques to achieve high accuracy and low power consumption with zero field calibration, saving you installation and commissioning time. Forming part of OMNIFLEX’s extensive OMNITERM range of industrial instrumentation, the OMNITERM LZI and LZD are designed to be DIN rail or surface mounted and are a space-saving 22.5mm wide. See the companion Omniterm LZB datasheet for dual binary inputs with surge protection. Copyright Omniflex ♦ Subject to change without notice Datasheet DSC2474A Revision 06 sheet 1 of 6

OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. Electrical Connections Loop Powered Two-wire Transmitter Earth Lead Single Channel OMNITERM LZI with Two-Wire Transmitter Four-wire (powered) 4-20mA Transmitter Link required Earth Lead Transmitter Power Single Channel OMNITERM LZI with Four-Wire Transmitter Switch 1 = Channel 1 Switch 2 = Channel 2 Switch 3 & 4 unused Switch ON = 1-5V out (Switch located on top edge of the module) Dual Channel OMNITERM LZD with two Two-Wire Transmitters Copyright Omniflex ♦ Subject to change without...

OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. Specifications Power Supply Operating Range Input Surge Suppression 10-30Volts dc Discharge Current C2474A LZI Supply Current (with outputs at 20mA) Two-Wire Transmitter Inputs (LZI and LZD) Input Current Range Operating Range 2-23mA Accuracy specified over 4-20mA Minimum loop voltage VLOOP = 21.4V minimum (measured at 23mA load, 10V supply) Isolation Test Voltage VLOOP = 28.0V maximum (measured at 2mA load, 30V supply) Unpacked / Packed Maximum loop voltage Minimum output load Maximum...

OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. Application Example 1 NOTE: The LZD may be substituted for the LZI in applications where two channels are required. Power Supply 8 Earth Shield at one end only Earth Lead Example 1: Interfacing a two-wire transmitter input to a Teleterm M2 Series RTU Application Example 2 Power Supply Switches closed for voltage inputs Earth Lead Earth Lead Switches closed for voltage inputs Example 2: Interfacing four transmitters to a Teleterm M2 Series RTU Copyright Omniflex ♦ Subject to change without...

OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. Power Supply 8 Earth Shield at one end only Analog Input Teleterm M2G Earth Lead Example 3: Interfacing a two-wire transmitter input to a Teleterm M2 Series RTU with power down circuit. Use this circuit to reduce power consumption in battery powered applications, when the two-wire transmitter need only be read intermittently. The program in the Teleterm M2 RTU must turn the power to the LZI on prior to reading and off again when complete. Application Example 4 Power Supply 8 Earth Shield...

OMNITERM LZI & LZD Current Loop Interface Model C2474A LZI (Single) & C2475A LZD (Dual) with Surge Suppression. Power Supply Switches open for current inputs Earth Lead Earth Lead Switches closed for voltage inputs Example 5: Interfacing four two-wire transmitters to an A-B MicroLogix 1000 series PLC. Typical Installation Installation example showing termination of surge protection ground wires to earthing bar. Keep all earth connections as short as possible. Copyright Omniflex ♦ Subject to change without notice Datasheet DSC2474A Revision 06 sheet 6 of 6