485ELC
1
05039.R3 11/03
www.protekdevices.com
HIGH SPEED ETHERNET DATA LINE PROTECTOR
Only One Name Means ProTek'TionTM
APPLICATIONS
Ethernet - 10/100 Base T
Catagory 5 Systems
RS-485 Serial Communication Lines
ISDN Equipment/Systems
Video Transmission Systems
Smoke Detector & Fire Alarm Systems
IEC COMPATIBILITY (EN61000-4)
61000-4-2 (ESD): Air - 15kV, Contact - 8kV
61000-4-4 (EFT): 40A - 5/50ns
61000-4-5 (Surge): 8/20s - 95A, Level 4 (Line-Gnd) & 48A, Level 4 (Line-Line)
FEATURES
LOW CAPACITANCE - 25PF
Designed for EIA Standard RS-485 Data Lines
Permanent Two-Stage 2 Line Pair Protector
Subnanosecond Response Time
Common & Differential Mode Protection
Automatic Reset - Does Not Interrupt Service
Effective Against Lightning, Inductive Switching and ESD
MECHANICAL CHARACTERISTICS
Weight: 142 grams (Approximate)
Flammability Rating UL 94V-0
Device Marking: Logo, Date Code, Terminal Designations & Part Number
DESCRIPTION
The 485ELC is low capacitance, two-stage transient voltage protector the provides
primary and secondary protection against lightning, inductive switching and electro-
static discharge (ESD) transient threats. The first stage diverts the transient current
through the ground terminal return path and the second stage clamps the voltage to a
safe level without interruption of service.
The 485ELC is designed to protect data lines, transmission lines, timing and control
interface circuits from common-mode (line-to-ground) or differential (line-line) tran-
sients. Terminals 1 & 2 and 3 & 4 are designed as line pairs. A transient voltage
suppressor is connected across each line pair for differential mode protection.
Capacitance over the operating voltage range is important. If capacitance is non-
linear, distortion, loss of data or access to the I/O port can occur (See Figure 1).
05039
FIGURE 1
LINEAR CAPACITANCE VS
NON-LINEAR CAPACITANCE
0 2 4 6 8 10
V
OP
- Data Line Operating Voltage - Volts
C - Capacitance - pF
1,000
100
1,0
Industry Standard
Low Capacitance
Solid State Protector
ProTek's 485ELC
485ELC
2
www.protekdevices.com
05039.R3 11/03
485ELC
DEVICE CHARACTERISTICS
MAXIMUM RATINGS @ 25C
MAXIMUM
CLAMPING
VOLTAGE
(8/20s)
@ 500A
V
C
VOLTS
MAXIMUM
LEAKAGE
CURRENT
@ 7V
OP
I
D
A
MAXIMUM
CAPACITANCE
@ 0-7V, 1MHz
C
pF
Peak Operatiing Line Voltage (V
OP
)
Operating Line Current (I
O
)
Maximum Transient Voltage
Maximum Transient Current
(8/20s waveform)
Operating & Storage Temperature
Response Time
ELECTRICAL CHARACTERISTICS @ 25C
7V
250mA
20kV
10kA/Wire
40kA/Protector
-55C to 100C
< 1 nanosecond
MAXIMUM
LINE
THRUPUT
RESISTANCE
R
OHMS
20
12
10
25
INSTALLATION INSTRUCTIONS
This product should be located as close as possible to the equipment
being protected. A low impedance grounding system is important to
maintain a low clamping voltage between the line-to-ground connection.
There are five (5) terminals on both the
line
and
equipment
side of the
485ELC - four data line terminals and two ground terminals. Both ground
terminals, as shown on the label, are connected internally. A single
ground connection is sufficient. However, it is recommended that both
ground connections be used for a lower impedance path to earth. This
connection can be made through the green AC power ground wire or a
known earth ground. The ground wire should be #14 stranded wire.
Incoming data lines are cut or disconnected from the equipment to insert
the 485ELC product. The
line
side of the terminals are to be connected
to data lines from the outside world or lines that carry the transient
threats into the equipment to be protected. The
equipment
side of the
terminals are to be connected to the equipment to be protected . The
location of the product should be such that these wires are as short as
possible. A #18 or 20 gauge wire can be used for these connections.
ProTek's data line protector is designed with a short circuit failure mode
to give maximum protection. A fuse, fussable link, or circuit breaker is
recommended for each data/signal line on the input (line) side of the
protector for those applications that require an open circuit failure mode.
Caution:
A low DC resistance ground may not be indicative of a good
lightning ground. Lightning contains a broad spectrum of frequencies -
up to 1 MHz. A low impedance path to ground at the transient frequen-
cies 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 potential under severe thunderstorm conditions.
For these applications, an additional protector may be necessary at the
equipment interface.
3
www.protekdevices.com
05039.R3 11/03
485ELC
COPYRIGHT ProTek Devices 2003
SPECIFICATIONS: ProTek reserves the right to change the electrical and or mechanical characteristics described herein
without notice (except JEDEC).
DESIGN CHANGES: ProTek reserves the right to discontinue product lines without notice, and that the final judgement
concerning selection and specifications is the buyer's and that in furnishing engineering and technical assistance,
ProTek assumes no responsibility with respect to the selection or specifications of such products.
PACKAGE OUTLINE & DIMENSIONS
ProTek Devices
2929 South Fair Lane, Tempe, AZ 85282
Tel: 602-431-8101 Fax: 602-431-2288
E-Mail:
sales@protekdevices.com
Web Site:
www.protekdevices.com
INSTALLATION DIAGRAM
485ELC Case Outline
EQUIPMENT
1
2
4
GND
3
2
1
4
GND
3
WARNING:
LINE
3.8" MAX
(95.5mm)
3.25"0.015"
(82.6mm0.38mm)
2.25" MAX
(57.2mm)
Mounting
Hole for #8
Screw
1.19" MAX
(30.2mm)
#6 Screw
0.61" MAX
(15.5mm)
Adhesive Mylar Label
Terminal Screw
1.125"
(30.2mm)
Unprotected Side Protected Side
1
2
GND
3
4
1
2
GND
3
4
(Line Input
T
e
r
m
inal)
Data Line From Outside World
(Equipment T
e
r
m
inal)
T
o
T
r
ansmit/Receiv
e
Circuits
Earth Ground
Earth Ground
Note:
Both ground terminals are common. Use second ground wire
to reduce impedance on long runs to earth ground connections
Terminal Strip
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