DT320 … / DT321 …Over-voltage protector

Product features

  • Transient voltage protection of 4-20 mA current loops
  • 3-stage protection
  • 10 kA surge (8 / 20 μs) withstand capability
  • 41 V max. output voltage
  • TS-35 rail mounting, 25 mm width
  • IP 65 enclosure versions

Type designation

DT320 DT321 overvoltage protector-type designation

Product description

The DT320 … / DT321 … Over-voltage protectors are designed to protect the 4-20 mA transmitter loop against over-voltage.
The units use 3 stages of protective components: spark gap, varistor and zener supressor. The maximum surge current withstand capability is 10 kV and the maximum output voltage is 41 V.
The types DT320 G and DT321 G have grounded outputs the DT320 F and DT321 F have floating outputs.
There are two versions of housing: the types DT320… are rail mounting for installation in cabinet, the types DT321… are IP65 protected for field installation.

Technical specifications

Safety data:
The connection terminals of the supply voltages are isolated from each other, the isolation is in compliance with the standard EN 61010-1, taking into consideration the following:
Pollution level:2
Measurement category:II
Input parameters:
Input signal:DC current
Range:0-35 VDC
Input current:120 mADC (max.)
Input-output serial resistor:30 ohm
Output parameters:
Output signal:DC current
Range:23.4 VDC (24 VDC input voltage at 20 mA output current)
Overvoltage protection:41 V (limiter)
Ambient conditions:
Operating temperature range:-20 - +60 °C
Relative humidity:90% (max., non condensing)
Place of installation:DT320 ... : cabinetDT321 ... : field
General data:
Housing:DT320 ... : terminal assembly box, rail
mounting on TS-35 rail
material: polyamide PA6.6
DT321 ... : polycarbonate box
Connection:screw-fixed type connection2 Pg 13.5 cable entry
screw-fixed type connection
Connection cable:2.5 mm2 (max.)3 × 1.5 mm2 (max.)
Dimensions:DT320 ... : 25 × 80 × 85 mm
(width × height × depth)
DT321 ... : 80 × 120 × 55 mm
(width × height × depth)
Weight:cca. 0.1 kgcca. 0.2 kg
Protection:IP 20IP 65
Detailed information see in operating instructions. The Manufacturer maintans the right to change the technical data!


Leaflet of productOperating Instruction

Application examples

DT320 F

DT320 F overvoltage protector-application example


DT320 G

DT320 G overvoltage protector-application example

Type selection and ordering

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