Features
n Low peak clamping voltage even during
severe current surges
n Ability to repeatedly protect against high
surge currents up to rated limits
n Convenient mounting and grounding to any
flat surface or to DIN-1 (TS-32) or DIN-3
(TS-35) rail
n Cable shields are passed through and
may be either grounded or arc-protected to
ground
n Vibration-resistant screw-type clamp
terminals
n 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.
Characteristics @ 25 °C
Tested per IEC 61000-4-5
1840-05
1840-12
1840-24 (1)
Maximum Operating Voltage
6 Vdc
13 Vdc
26 Vdc
Maximum Breakdown Voltage (L-L) and (L-G)
8 Vdc
15 Vdc
30 Vdc
Standard Model
(1) Systems operating at 18 V or above and experiencing current above 500 mA (including short-term inrush current at start-up) may latch the
overcurrent protection feature in blocking mode. This will prevent system operation until the power is removed.
Surge Life
100 Amps 10 x 1000 µsec.........................................................................................................300 operations min.
100 Amps 10 x 1000 µsec.........................................................................................................300 operations min.
500 Amps 10 x 1000 µsec.........................................................................................................50 operations min.
1000 Amps 10 x 1000 µsec.......................................................................................................10 operations min.
3 kA, 6 kV / 8 x 20 µsec Combination Wave.............................................................................100 operations min.
10 kA / 8 x 20 µsec....................................................................................................................10 operations min.
20 kA / 8 x 20 µsec....................................................................................................................5 operations min.
Breakdown Voltage.................................................................................................................................See table*
ESD @ 8 kV............................................................................................................................................10 operations min.
Shield ARC Protection 6 kV / 3 kA...........................................................................................................5 operations min.
Capacitance @ 1 MHz............................................................................................................................L/G: 45 pF, L/L: 35 pF
Series Resistance...................................................................................................................................12 Ω typical
Maximum Load Continuous Current........................................................................................................220 mA
DC Leakage Current at Rated L/G Voltage.............................................................................................< 10 µA
Blocking Current......................................................................................................................................300 mA; typical 450 mA
Signal/Data Attenuation...........................................................................................................................3 db @ 30 MHz with 50 Ω termination
Operating Temperature............................................................................................................................-40 ºC to +60 ºC
Response Time.......................................................................................................................................< 1 µsec
Wire Size.................................................................................................................................................20 AWG
* Custom voltages are available upon request. Please visit www.bourns.com/docs/Product-Datasheets/SMBJ.pdf for custom allowable voltages.
Lead-time may be extended for some custom voltages.
WARNING Cancer and Reproductive Harm
www.P65Warnings.ca.gov
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page
of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
BALANCED OR DIFFERENTIAL INTERFACE, SUCH AS RS-422
P/N 1840
L2
L3
L3
GND
E1
L1
E2
E3
GND
L1
RCVR
E1
1840 Series – Signal and Dataline Protector
EQPT. COMMON
AND/OR GND.
Typical Connections
How To Order
UNBALANCED INTERFACE, TWO INDIVIDUAL CIRCUITS, SUCH AS RS-232
Unbalanced Interface,
Two Individual Circuits, Such as RS-232
Model No. Designator
TBU
L1
XMTR
E3
L1
®
XMTR
E3
RCVR
E1
COMMON
GND.
COMMON
GND.
CONTROL ROOM
BALANCED
OR DIFFERENTIAL
INTERFACE,
SUCH AS RS-422
Balanced or Differential
Interface,
Such
as RS-422
~
~
E3
GND
E1
EQPT. COMMON
AND/OR GND.
E3
GND
L1 P/N 1840
E1
L2
E2
BOURNS
E3
L3
PROTECTOR
E3/L3 GROUNDING LINK
P/NL11669GND E1
L3
48.51
(1.91)
L3
COMMON
GND.
L1
83.31
COMMON
(3.28)
GND.
COMMON
GND.
EQPT. COMMON
AND/OR GND.
XMTR
RCVR
18.80RCVR
(0.74)
3.18
(0.125)
2.36
(0.093)
ALIGNMENT PIN
XMTR
EQPT. COMMON
AND/OR GND.
COMMON
GND.
COMMON
GND.
FEED-THRU(E3/L3)
GROUNDING SCREW
-
L3
L2L1
DIN-1 RAIL
(TS-32/EN50035)
EQPT. COMMON
AND/OR GND.
UNBALANCED INTERFACE, TWO INDIVIDUAL CIRCUITS, SUCH AS RS-232
Current Loop, 4-20
mA
CURRENT LOOP, 4-20 mA
CONTROL ROOM
BLDG. 1
XMTR
E3
E3
L3
L3
GND
E1 GND
E1
L1
L1
I
RECEIVER
1-5 VOLTS
File No.EQPT. COMMON
1800SERS3
AND/OR GND.
GROUNDING SCREW
RED
L2 P/N 1840
E2RED /WHITE
BLACK /WHITE
BOURNS
L3
1669
L1
BLK
GND
BOURNS
PROTECTOR
COMMON
P/N 1669
GND.
COMMON
COMMON
GND.
GND.
E3
E1
GREEN
MOUNTING/GROUNDING SCREW
RCVR
XMTR
28.96
(1.14)
45.47
(1.79)
EQPT. COMMON
49.02
AND/OR GND.
(1.93)
DIN-3 RAIL
(TS-35/EN50022)
DIN-1 RAIL
(TS-32/EN50035)
CURRENT
LOOP, 4-20 mA
CONTROL ROOM
~
~
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
XMTR
I
clamp is not used) should
beE2connected
to the facility
ground via an AWG #6 or larger copper
P/N 1840
RED
L2
/WHITE
RED
wire. ThisPOWER
wire should
Single point
grounding will provide
250 be as short and straight as possible.
BLACK /WHITE
BOURNS
E3
L3
SUPPLY
OHMS
1669
better protection
and
will permitGND
the protector to be located
a distance from
GREEN the equipment.
L1
~
~
I
File No.
1800SERS3
L1
COMMON
GND.
BOURNS
PROTECTOR
P/N 1669
MM
(INCHES)
Circuit Diagram
BLK
-
RECEIVER
1-5 VOLTS
DIMENSIONS:
TBU® DEVICE
E1
+
E1
49.02
(1.93)
+
L2
L2
-
250
OHMS
P/N1840
1840
E2 P/N
E2
~
~
~
FEED-THRU(E3/L3)
I
8-32UNF-2A
17.80
(0.70)
LG
28.96
9.53
(1.14)
(0.375)
Add -A3 to base model number for
DIN-3 clamp.
(Example: 1840-12-A3)
BLDG. 2
~~
~~
XMTR
POWER
SUPPLY
RCVR
SHIELD
(0.74)
+
~
~~
~
File No.
1800SERS3
RCVR
E3
GND
E2E1P/N 1840
~
~
~~
File No.
1800SERS2
I
RECEIVER
1-5 VOLTS
~
~
XMTR
XMTR
E3 18.80
Add -A1 to base model number for
DIN-1 clamp.
(Example: 1840-12-A1)
LINE
L1 L3 L2
EQPT
E2 E3 E1
POWER
SUPPLY
E2
How To Order (Clamp)
EQPT. COMMON
AND/OR GND.
I
UNBALANCED
INTERFACE, TWO INDIVIDUAL CIRCUITS, SUCH
AS RS-232
BLDG.
BLDG.
2
GND
RED
E2 P/N 11840
L2
RED /WHITE
250
BLACK /WHITE
BOURNS
E3
L3
OHMS
1669
GREEN
GND
1840 2
BLDG.
BLDG.
L2 P/N
E2
E2
L2L1
E1P/N11840
BLK
E1
83.31
(3.28)
EQPT. COMMON
AND/OR GND.
COMMON
COMMON
GND. CURRENT LOOP, 4-20 mA GND.
EQPT. COMMON
AND/OR GND.
RCVR
E2 E1
GND
LINE
E3
L3
L1
EQPT. COMMON
AND/OR GND.
E2
L3
L2 L1
L3
GND
E1
File No.
1800SERS2
L2
L1
BLDG. 2
L2 P/N 1840
P/N 1840
GND
~
~
E2
E1
RCVR
P/NGND
1840
~
~
L3
~~
~~
L2
E3
EQPT
E2 E3 E1
BLDG. 1
E2 P/N 1840
DEVICE
GND
Voltage
SOLID-STATE
05 = 5 Vdc
LOW
12 = 12 Vdc
VOLTAGE
PROTECTION
24 = 24 Vdc
TBU DEVICE
L2
48.51
Clamp (1.91)
SHIELD
A1 = DIN-1
SHORTING
E3/L3 GROUNDING LINK
A3 = DIN-3
LINK
BALANCED
BLDG.OR
1 DIFFERENTIAL INTERFACE, SUCH AS RS-422
BLDG. 2
XMTR
1840 - nn - An
®
EQUIPMENT
COMMON
GND.
COMMON
GND.
L2
TBU® DEVICE
SOLID-STATE
LOW
VOLTAGE
PROTECTION
E2
E3
SHIELD
EQUIPMENT
EQPT. COMMON
AND/OR GND.
LINE
L1 L3 L2
L2
LINE
File No.
1800SERS2
P/N 1840
E3
~
~
E2
XMTR
BLDG. 2
~
~
BLDG. 1
SHIELD
SHORTING
LINK
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
LINE
1 L3 L2
EQPT
E2 E3 E1
GND
SOLID-STATE
LOW
VOLTAGE
PROTECTION®
TBU DEVICE
E2
E3
SHIELD
SHIELD
SOLID-STATE
LOW
VOLTAGE
PROTECTION
SHIELD
SHORTING
LINK
SHORTING
LINK
E1
E2
E3
EQUIPMENT
LINE
LINE
TBU® DEVICE
L2
L2
EQUIPMENT
TBU® DEVICE
E1
TBU® DEVICE
L1
L1
SHIELD
1840 Series – Signal and Dataline Protector
Product Dimensions
LINE
L1 L3 L2
EQPT
E2 E3 E1
EQPT
E2 E3 E1
LINE
L1 L3 L2
GND
GND
48.51
(1.91)
48.51
(1.91)
18.80
(0.74)
E3/L3 GROUNDING LINK
E3/L3 GROUNDING LINK
83.31
(3.28)
18.80
(0.74)
3.18
(0.125)
2.36
(0.093)
ALIGNMENT PIN
83.31
(3.28)
DIMENSIONS:
MM
(INCHES)
3.18
(0.125)
2.36
(0.093)
PIN
ALIGNMENT
8-32UNF-2A
17.80
(0.70)
LG
9.53
(0.375)
8-32UNF-2A
17.80
(0.70)
LG
9.53
(0.375)
FEED-THRU(E3/L3) FEED-THRU(E3/L3)
GROUNDING SCREW GROUNDING SCREW
MOUNTING/GROUNDING SCREW
MOUNTING/GROUNDING SCREW
28.96
(1.14)
28.96
(1.14)
49.02
(1.93)
DIN-1 RAIL
(TS-32/EN50035)
DIN-1 RAIL
(TS-32/EN50035)
49.02
(1.93)
45.47
(1.79)
45.47
(1.79)
DIN-3 RAIL
(TS-35/EN50022)
DIN-3 RAIL
(TS-35/EN50022)
Asia-Pacific: Tel: +886-2 2562-4117 • Email: asiacus@bourns.com
EMEA: Tel: +36 88 885 877 • Email: eurocus@bourns.com
The Americas: Tel: +1-951 781-5500 • Email: americus@bourns.com
www.bourns.com
REV. D 03/20
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
Legal Disclaimer Notice
This legal disclaimer applies to purchasers and users of Bourns® products manufactured by or on behalf of Bourns, Inc. and its
affiliates (collectively, “Bourns”).
Unless otherwise expressly indicated in writing, Bourns® products and data sheets relating thereto are subject to change
without notice. Users should check for and obtain the latest relevant information and verify that such information is current and
complete before placing orders for Bourns® products.
The characteristics and parameters of a Bourns® product set forth in its data sheet are based on laboratory conditions, and
statements regarding the suitability of products for certain types of applications are based on Bourns’ knowledge of typical
requirements in generic applications. The characteristics and parameters of a Bourns® product in a user application may vary
from the data sheet characteristics and parameters due to (i) the combination of the Bourns® product with other components
in the user’s application, or (ii) the environment of the user application itself. The characteristics and parameters of a Bourns®
product also can and do vary in different applications and actual performance may vary over time. Users should always verify
the actual performance of the Bourns® product in their specific devices and applications, and make their own independent
judgments regarding the amount of additional test margin to design into their device or application to compensate for
differences between laboratory and real world conditions.
Unless Bourns has explicitly designated an individual Bourns® product as meeting the requirements of a particular industry
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Bourns® products are not recommended, authorized or intended for use in nuclear, lifesaving, life-critical or life-sustaining applications, nor in any other applications where failure or malfunction may result in personal injury, death, or severe property or
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Bourns expressly identifies those Bourns® standard products that are suitable for use in automotive applications on such
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PDF: http://www.bourns.com/docs/Legal/disclaimer.pdf
C1753 05/17/18R