M-system MD74R, Instruction Manual

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EM-8058 Rev.6 P. 1 / 4
INSTRUCTION MANUAL
LIGHTNING SURGE PROTECTOR FOR
RS-485 / RS-422
(ultra-slim)
MODEL
MD74R
BEFORE USE ....
Thank you for choosing M-System. Before use, please check
contents of the package you received as outlined below.
If you have any problems or questions with the product,
please contact M-System’s Sales Office or representatives.
■
PACKAGE INCLUDES:
Surge protector ....................................................................(1)
■
MODEL NO.
Confirm Model No. marking on the product to be exactly
what you ordered.
■
INSTRUCTION MANUAL
This manual describes necessary points of caution when
you use this product, including installation, connection and
basic maintenance procedures.
LIMITATION APPLICABLE TO M-RESTER
The M-RESTER will protect electronics equipment from
damage caused by lightning by absorbing most of the
surge voltages.
However, M-RESTER may not be effective against cer-
tain extremely high voltages caused by a direct or almost
direct hit by lightning.
M-RESTER must be installed according to this installa-
tion / instruction manual.
GENERAL
■
FUNCTION & FEATURES
• High discharge current capacity 20 kA (8 / 20 µs), 1 kA
(10 / 350 µs)
• Ultra-thin 7-mm-wide module can be mounted in high
density
• Excellent protection employing multi-stage SPD circuits
• DIN rail mounting and grounding
• Shield terminal provided
■
SPECIFICATIONS
See Table 1.
Table 1. Specifications
LINE TO LINE LINE TO SG LINE/SG TO EARTH SHLD TO EARTH
Max. continuous operating voltage (Uc) ±5V 5V ±160V ±160V *
1
Voltage protection level (Up)
@4kV (1.2 / 50 µs) ±25V 25V ±800V ±800V *
1
Leakage current @Uc ≤ 200µA ≤ 200µA ≤ 10µA ≤ 10µA*
1
Response time ≤ 4 nsec. ≤ 4 nsec. ≤ 20 nsec. ≤ 20 nsec.*
1
Approx. capacitance @ 100 kHz 300 pF 300 pF 100 pF 100 pF
Max. discharge current (Imax) 20kA (8 / 20 µs), 1.0kA (10 / 350 µs)
Nominal current (I
N
) 100mA
Internal series resistance 2Ω ±10% per line
Input attenuation -0.5 dB max. @DC...2.0 MHz, Z0 = 110Ω
*1. Values for the MD74R-FF. Shortcircuited for the MD74R-FG.
056 222 38 18 mailbox@sentronic.com www.sentronic.com
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