DIN-I-420: Din rail 4... 20mA loop isolator - Arian S. A.
DIN-I-420: Din rail 4... 20mA loop isolator - Arian S. A.
DIN-I-420: Din rail 4... 20mA loop isolator - Arian S. A.
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Industrial Control & Instrumentation<br />
<strong>DIN</strong>-I-<strong>420</strong>:<br />
<strong>Din</strong> <strong>rail</strong> <strong>4.</strong>.. <strong>20mA</strong> <strong>loop</strong> <strong>isolator</strong><br />
l<br />
l<br />
Loop powered, does not need additional power supply<br />
Service and 5 years guarantee.<br />
GENERAL DESCRIPTION<br />
The device generates in its output a <strong>4.</strong>.. <strong>20mA</strong> <strong>loop</strong> identical to the one present in its<br />
input but optoisolated.<br />
Galvanic isolation eliminates the problems produced by ground potencial differences<br />
in the plant and reduces the ones produced by electromagnetic interference.<br />
Common applications are to create safe barriers and floating ground references for<br />
interconnecting several equipment without creating current return conflicts.<br />
TECNICAL SPECIFICATIONS<br />
INPUT: Voltage drop: 3.6 V max.<br />
OUTPUT: Maximum operation voltage. 30 V<br />
Minimum operation voltage.<br />
3.6 V + 20 mA * RL<br />
Isolation:<br />
4000 V min.<br />
Temperature stability:<br />
25 ppm / °C max.<br />
Long term stability:<br />
20 ppm / año max.<br />
CONSTRUCTION: Material: Poliester; IP65<br />
Total dimensions:<br />
22 mm wide, 75 mm heigth , 110 mm deep.<br />
Assembly<br />
Rail <strong>DIN</strong><br />
Weight:<br />
100 grams.<br />
Operation temperature:<br />
-10 ... 50 °C.<br />
CONNECTIONS<br />
9 Input<br />
<strong>4.</strong>.20 mA<br />
+<br />
_<br />
Vz= 3.6V<br />
7<br />
Output<br />
V. drop<br />
3.6V<br />
6<br />
+<br />
<strong>4.</strong>..20 mA<br />
4<br />
_<br />
+V<br />
+V max.= 30V<br />
+V min. = 3.6V + <strong>20mA</strong>*RL<br />
RL<br />
C Copyright ARIAN S.A. 2001.<br />
<strong>DIN</strong>-I-<strong>420</strong>-E3-10/01, http://www.arian.cl 1
OPERATION<br />
The <strong>DIN</strong>-I-<strong>420</strong> operation is based on a opto-<strong>isolator</strong> composed by a light emiting<br />
diode (LED) on the input side, a reciever photo transistor on the output side and<br />
another reciever photo tranasistor in the input side. This last one feebacks for<br />
compasating and linealizing the LED light intensity variations caused by the operating<br />
temperature.<br />
The input circuit makes a 3.6V drop on the input <strong>loop</strong> for feeding the LED and<br />
behaves similar to a zener diode.<br />
The ouput current <strong>loop</strong> feeds the current regulator circuit drived by the photo transistor.<br />
This current <strong>loop</strong> feeding induces a 3.6V drop on the output <strong>loop</strong>.<br />
APPLICATIONS<br />
Two common ground instruments <strong>4.</strong>.20 mA input<br />
+ 24 V<br />
+ 24 V<br />
Sensor<br />
<strong>DIN</strong>-I-<strong>420</strong><br />
+ 24 V<br />
Gnd<br />
9<br />
6<br />
Two instruments, a controller and a<br />
monitor need to have <strong>4.</strong>.. <strong>20mA</strong> input<br />
from the same sensor and<br />
simultaneuslly to have common<br />
grounds.<br />
The problem appears with the common<br />
ground requirement, because it is<br />
impossible to make a <strong>4.</strong>..<strong>20mA</strong> <strong>loop</strong><br />
series connection through both<br />
instruments.<br />
Lazo 1<br />
<strong>4.</strong>..20 mA<br />
7<br />
Input<br />
Output<br />
+<br />
4<br />
_<br />
Lazo 2<br />
<strong>4.</strong>..20 mA<br />
Gnd<br />
Monitor<br />
RL<br />
The solution is to generate a second<br />
identical but isolated current <strong>loop</strong> with<br />
floating ground for the monitor<br />
instrument.<br />
Controlador<br />
Gnd<br />
RL<br />
PART CODE:<br />
<strong>DIN</strong>-I-<strong>420</strong><br />
FOR MORE INFORMATION:<br />
ARIAN S. A.<br />
Teniente Montt 1932, Nuñoa,<br />
Santiago, Chile<br />
Fone/Fax 56-2-4249363<br />
arian@arian.cl<br />
www.arian.cl<br />
<strong>DIN</strong>-I-<strong>420</strong>-E3-10/01, http://www.arian.cl 2