Features ■ Low peak clamping voltage even during ■ Cable shields are passed through and severe current surges ■ Ability to repeatedly protect against high surge currents up to rated limits ■ Convenient mounting and grounding to any flat surface or to DIN-1 (TS-32) or DIN-3 (TS-35) rail may be either grounded or arc-protected to ground ■ Vibration-resistant screw-type clamp terminals ■ Flame-resistant epoxy-filled housing 1840 Series – Signal and Dataline Protector The Bourns® 1840 Series Signal and Dataline Protectors are designed to protect sensitive electronic circuits and components from damaging surge voltages and currents. Their extremely fast response and low clamping voltages make them particularly suitable for the protection of sensitive signal and datalines associated with computer, data communication, instrumentation, broadcasting and industrial controls. They may be used directly with EIA standard interfaces RS-232, RS-422, RS-423, RS-485 and with 4-20 mA and 50 mA instrumentation loops. The Model 1840 Series Signal and Dataline Protectors are fast, rugged and capable of protecting against fast rising voltage transients as well as the severe current surges associated with lightning discharges, in each case up to rated limits. Method of Operation The Bourns® 1840 Series are heavy-duty, multi-staged protectors. A solid-state 3rd stage protection component intercepts the leading edge of the surge within sub-nanosecond response time. Within microseconds, a primary stage 3-electrode common chambered heavy-duty gas discharge tube capable of handling 20,000 ampere lightning currents operates and crowbars the majority of the surge energy to ground. The Model 1840 also utilizes Bourns’ TBU® High-Speed Protector (HSP) technology as a key 2nd stage. Any current through the protector exceeding 300 mA will cause the TBU® HSP to quickly transition into a high impedance state, thus isolating any harmful voltage and/or current from damaging the protected equipment. The gas discharge tube protector remains in the crowbar state until the surge has passed and line voltages return to safe levels. The TBU® HSP then automatically restores the line to normal operation by resetting to a low impedance state. There is no need for resetting a breaker or replacing a fuse to address a transient surge event. Application Protectors are generally placed at each end of a signal, dataline or current loop. In the case of daisy-chain configurations (such as RS-485), protectors are placed at each node. Related Bourns® Protectors For outdoor applications with 1/2-inch NPT ports (such as field-mounted 4-20 mA transmitters), please refer to the Bourns® Model 1669 Series Protector. In this application, the mixed use of a Model 1840 Series Protector at the controller and a Model 1669 Series Protector at the field is recommended. Circuit Diagram 1840-05 Maximum Breakdown Voltage (L-L) and (L-G) 8V 1840-12 15 V L1 1840-24 30 V L2 Surge Life 100 Amps 10 x 1000 μsec............................................ 100 Amps 10 x 1000 μsec............................................ 500 Amps 10 x 1000 μsec............................................ 1000 Amps 10 x 1000 μsec.......................................... 3 kA, 6 kV / 8 x 20 μsec Combination Wave ................ 10 kA / 8 x 20 μsec....................................................... 20 kA / 8 x 20 μsec....................................................... Breakdown Voltage............................................................ ESD @ 8 kV ...................................................................... Shield ARC Protection 6 kV / 3 kA..................................... Capacitance @ 1 MHz ...................................................... Series Resistance.............................................................. Maximum Load Continuous Current .................................. DC Leakage Current at Rated L/G Voltage ....................... Blocking Current ................................................................ Signal/Data Attenuation ..................................................... Operating Temperature...................................................... Response Time.................................................................. Wire Size ........................................................................... TBU® DEVICE LINE Standard Model TBU® DEVICE E1 SOLID-STATE LOW VOLTAGE PROTECTION 300 operations min. 300 operations min. 50 operations min. 10 operations min. 100 operations min. 10 operations min. 5 operations min. See table* 10 operations min. 5 operations min. L/G: 45 pF, L/L: 35 pF 12 Ω typical 220 mA < 10 μA 300 mA; typical 450 mA 3 db @ 30 MHz with 50 Ω termination -40 ºC to +60 ºC < 1 μsec 20 AWG *Custom voltages are available upon request. Please visit www.bourns.com/data/global/ pdfs/SMBJ.pdf for custom allowable voltage. Lead-time may be extended for some custom voltages. E2 E3 SHIELD EQUIPMENT Characteristics @ 25 °C SHIELD SHORTING LINK Asia-Pacific: Tel: +886-2 2562-4117 Fax: +886-2 2562-4116 EMEA: Tel: +36 88 520 390 Fax: +36 88 520 211 The Americas: Tel: +1-951 781-5500 Fax: +1-951 781-5700 www.bourns.com Specifications are subject to change without notice. The device characteristics and parameters in this data sheet can and do vary in different applications and actual device performance may vary over time. Users should verify actual device performance in their specific applications. 1840 Series – Signal and Dataline Protector Typical Connections How To Order 1840 - nn - An Unbalanced Interface, Two Individual Circuits, Such as RS-232 Model No. Designator E2 P/N 1840 L2 E3 RCVR E1 GND EQPT. COMMON AND/OR GND. P/N 1840 L2 L3 L1 E2 GND L1 RCVR XMTR E1 COMMON GND. COMMON GND. Voltage 05 = 5 V 12 = 12 V 24 = 24 V E3 L3 ~ ~ XMTR BLDG. 2 ~ ~ BLDG. 1 Clamp A1 = DIN-1 A3 = DIN-3 EQPT. COMMON AND/OR GND. How To Order (Clamp) Add -A1 to base model number for DIN-1 clamp. (Example: 1840-12-A1) Balanced or Differential Interface, Such as RS-422 XMTR P/N 1840 L2 E3 E1 L2 P/N 1840 L1 L1 FEED-THRU(E3/L3) E2 GROUNDING SCREW E3 L3 L3 GND ~ ~ E2 BLDG. 2 ~ ~ BLDG. 1 GND RCVR E1 28.96 (1.14) EQPT. COMMON AND/OR GND. COMMON GND. COMMON GND. EQPT. COMMON AND/OR GND. 49.02 (1.93) DIN-1 RAIL (TS-32/EN50035) Current Loop, 4-20 mA CONTROL ROOM 250 OHMS E3 E1 ~ ~ P/N 1840 L2 RED GND L1 RED /WHITE BLACK /WHITE BOURNS 1669 L3 ~ ~ E2 POWER SUPPLY Add -A3 to base model number for DIN-3 clamp. (Example: 1840-12-A3) XMTR I GREEN MOUNTING/GROUNDING SCREW BLK File No. 1800SERS3 RECEIVER 1-5 VOLTS + - I BOURNS PROTECTOR P/N 1669 COMMON GND. 45.47 (1.79) Grounding: The 8-32 mounting screw and attached clamp, and hence the DIN-1 (TS-32) or DIN-3 (TS-35) rail, serve as the protector ground. The rail (or 8-32 mounting screw if the clamp is not used) should be connected to the facility ground via an AWG #6 or larger copper wire. This wire should be as short and straight as possible. Single point grounding will provide better protection and will permit the protector to be located a distance from the equipment. DIN-3 RAIL (TS-35/EN50022) DIMENSIONS: MM (INCHES) Product Dimensions LINE L1 L3 L2 EQPT E2 E3 E1 GND 48.51 (1.91) DIMENSIONS: E3/L3 GROUNDING LINK 83.31 (3.28) 18.80 3.18 (0.74) (0.125) 2.36 (0.093) ALIGNMENT PIN MM (INCHES) 9.53 (0.375) 8-32UNF-2A 17.80 (0.70) LG REV. A 02/14 Specifications are subject to change without notice. The device characteristics and parameters in this data sheet can and do vary in different applications and actual device performance may vary over time. Users should verify actual device performance in their specific applications.