Only One Name Means ProTek’Tion™
The 422ELC is low capacitance, two-stage transient voltage protector that provides primary and secondary protec-
on against lightning, inducve switching and electrostac discharge (ESD) transient threats. The rst stage diverts
the transient current through the ground terminal return path and the second stage clamps the voltage to a safe level
without interrupon of service.
The 422ELC is designed to protect data lines from dierenal (line-line) and common-mode (line-to-ground) transients.
Terminals 1 & 2 and 3 & 4 for the 422ELC are designed as line pairs. A transient voltage suppressor is connected
across each line pair for dierenal mode protecon. Each line pair is referenced to ground.
This product can also be used on telephone, signal/data lines, security, ming and control interface circuits. For most
applicaons, the product should be located as close as possible to the equipment being protected. A low impedance
grounding system is important to maintain a low voltage clamp between the line-to-ground connecon. Capacitance
over the operang voltage range is important. If capacitance is nonlinear, distoron, loss of data or access to the I/O
port can occur (See Figure 1).
• RS-422 Data Lines
• Digital Process Control Loop
• Long Line Digital Systems
• Digital Transmission
• Telemetry Systems
• Smoke Detector and Fire Alarm Systems
• Compable with IEC 61000-4-2 (ESD): Air - 15kV, Contact - 8kV
• Compable with IEC 61000-4-4 (EFT): 40A - 5/50ns
• Compable with IEC 61000-4-5 (Surge): 95A, 8/20µs, Level 4 (Line-
Gnd) & 48A, Level 4 (Line-Line)
• Low Capacitance - 25pF
• Designed for EIA Standard RS-422 Data Lines
• Permanent Two-Stage 2 Line Pair Protector
• Subnanosecond Response Time
• Common & Dierenal Mode Protecon
• Automac Reset - Does Not Interrupt Service
• Eecve Against Lightning, Inducve Switching and ESD
• Approximate Weight: 142 grams
• Flammability Rang UL 94V-0
Industry
Standard Low
Capacitance TVS
Protector
ProTek Device
Only One Name Means ProTek’Tion™
Peak Operang Line Voltage VOP ±12 Volts
Operang Line Current IO200 mA
Transient Voltage - 20 kV/Wire
Transient Current - 8/20µs waveform - 10 kA/Wire
Transient Current - 8/20µs waveform - 40 kA/Wire
Operang Temperature TA-55 to 100 °C
Storage Temperature TSTG -55 to 100 °C
Response Time - < 1 ns
422ELC 30.0 30.0 12 1 25
Only One Name Means ProTek’Tion™
UNPROTECTED SIDE PROTECTED SIDE
2
1
GND
3
4
2
1
GND
3
4
Earth Ground Earth Ground
(Line Input Terminal)
Data Line from Outside World
(Equipment Terminal)
To Transmit/Receive Circuits
Note: Both ground terminals are common. Use second ground wire
to reduce impedance on long runs to earth ground connecons.
There are ve (5) terminals on the LINE SIDE and ve (5) terminals on the EQUIPMENT SIDE of the 422ELC, 4 data lines and one ground. Both grounds are connected
together internally. A single low impedance ground is sucient. Incoming data lines are cut or disconnected from the equipment to insert the 422ELC product. The
incoming lines are to be connected to the line side terminals as the equipment side lines are connected to the equipment side terminals. The locaon of the product
should be as close to the equipment as possible. The 422ELC series is designed with a short circuit failure mode to give maximum protecon. A fuse, fusible link, or
circuit breaker is recommended for each data/signal line on the input side for those that require an open circuit failure mode.
A low DC resistance ground may not be a good ground. Lightning contains a broad spectrum of frequencies up to 1 MHz. A low impedance path to ground
at the transient frequencies is necessary. A ground strap is recommended or a #6 AWG stranded wire. For wire lengths over 1.5 meters, there may be some excessive
line to earth potenal under severe thunderstorm condions.
Only One Name Means ProTek’Tion™
A
B
C
D
E
F
Mounng Hole
for #8 Screw
Terminal Screw
A
Adhesive Mylar Label
Terminal Strip
#6 Screws
EQUIPMENT
LINE
4 3 GND 2 1
1 2 GND 3 4
WARNING
A - 95.5 - 3.8
B 82.22 82.98 3.235 3.265
C - 57.2 - 2.25
D - 30.2 - 1.125
E - 15.5 - 0.61
F - 30.2 - 1.19
422ELC Logo, Date Code, Terminal Designaons and Part Number
Only One Name Means ProTek’Tion™
COPYRIGHT © ProTek Devices 1998 - This literature is subject to all applicable copyright laws and is not for resale in any manner.
SPECIFICATIONS: ProTek reserves the right to change the electrical and or mechanical characteriscs described herein without noce.
DESIGN CHANGES: ProTek reserves the right to disconnue product lines without noce and that the nal judgement concerning selecon and specicaons is the buyer’s and that in furnishing engineering
and technical assistance. ProTek assumes no responsibility with respect to the selecon or specicaons of such products. ProTek makes no warranty, representaon or guarantee regarding the suitability of
its products for any parcular purpose, nor does ProTek assume any liability arising out of the applicaon or use of any product or circuit and specically disclaims any and all liability without limitaon special,
consequenal or incidental damages.
LIFE SUPPORT POLICY: ProTek Devices products are not authorized for use in life support systems without wrien consent from the factory.
In business more than 20 years, ProTek Devices™ is a privately-held company located in Tempe, Arizona, that oers a product line of tran-
sient voltage suppressors (TVS); avalanche breakdown diodes; steering diode TVS arrays and other surge suppressor component products.
These TVS devices protect electronic systems from the eects of lightning, electrostac discharge (ESD), nuclear electromagnec pulses
(NEMP), inducve switching and EMI / RFI. ProTek Devices also oers high performance interface and linear products that include analog
switches; mulplexers; LED drivers; audio control ICs; RF and related high frequency products. The analog devices work in a host of con-
sumer; industrial; automove and other applicaons.
2929 South Fair Lane
Tempe, Arizona 85282
USA
General: 602-431-8101
Sales: & Markeng: 602-414-5109
Customer Service: 602-414-5114
Product Technical Support: 602-414-5107
General: 602-431-2288
Sales: sales@protekdevices.com
Customer Service: service@protekdevices.com
Technical Support: support@protekdevices.com
8 Ubi Road 2, #06-19
Zervex
Singapore - 408538
Tel: +65-67488312
Fax: +65-67488313
www.protekdevices.com
