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DM4391
4 to 20 MA INPUT/OUTPUT
LOOP POWERED ISOLATOR

FEATURES
bulletProvides a Fully Isolated 4/20 mAdc Output Proportional to 4/20 mAdc Input
bulletOperating Power Derived from the Input Current
bulletSingle or Dual Channel (DM4391-1, DM4391-2)
bulletPlug-in Terminal Blocks
bulletStandard DIN rail Mount With Easy Snap-on Snap-off
bulletUser Write-on Label
bulletConnections Readily Accessible From The Front
bulletPermanent Warranty

DESCRIPTION

The DM4391 is a loop powered isolator that provides an isolated 4/20 mA output proportional to a 4/20 mA input.

All operating power for the circuit is derived from the 4/20 mA input current.

The product is useful for breaking ground loops and for creating a 4/20 mA output in locations where primary power is not available.

A unique feedback system allows the DM4391 to achieve the same linearity as powered isolators and to drive loads from 0 ohms to 1000 ohms without affecting linearity.

The product is available as a single channel or a dual channel unit. The dual channel unit has two totally separate circuits that are fully isolated from each other.

Connections are made via two 4-pin plug-in terminal blocks. These terminal blocks allow the product to be removed without unwiring the connections.

TYPICAL APPLICATIONS

Eliminates ground loops and common mode signals in 4/20 mA current loops for isolation, buffering, noise reduction, especially where line power is NOT available.

MOUNTING

The module mounts on a standard H-35 DIN rail. A spring latch holds it in place. The module is demounted by using a screw driver to release the latch at the bottom of the module.

SPECIFICATIONS

INPUT
4/20 mA

INPUT VOLTAGE DROP
5+(I(mA)*(Load+76.5)/850)

Typical Drop
Drop (V)
6.8
9.2
12.7
18.6
24.5
30.3		 Load(ohms) at 20 mA
0
100
250
500
750
1000

OUTPUT
Output Current
  4/20 mA

Drive Capability
  0 to 1000 ohms

Input to Output Linearity
  ±0.02% of span

Output Ripple
  (peak to peak)
  <0.1% of span

ISOLATION, OUTPUT / INPUT
 Breakdown
  >1000 VAC RMS Sinewave
Resistance
  >500 megohms

OPERATING TEMPERATURE
 14°F to 140°F
-10°C to  60°C

TEMPERATURE STABILITY
±(0.02% of span)/°C

COMMON MODE REJECTION
 >100 dB, DC to 60 Hz

CONNECTIONS   (Labeled)
DM4391-1
Input  (+)
Input  (-)
Output  (+)
Output  (-)
DM4391-2
Input 1  (+)
Input 1  (-)
Output 1  (+)
Output 1  (-)
Input 2  (+)
Input 2  (-)
Output 2  (+)
Output 2  (-)