VariTrans A 21000

Isolated Standard Signal Conditioner


The first standard-signal isolation amplifier with broad-range power supply in the 6-mm class.


  • Broad-range power supply 24 to 110 V DC (+/-25 %) and 110 to 230 V AC (+/-10 %)
  • Standards-compliant personal and plant protection Protective separation according to EN 61140
  • 3-port isolation Prevention of incorrect measurements caused by potential differences
  • Ideal value for money High accuracy and isolation – 2.5 kV AC test voltage
  • Easy installation DIN rail bus connectors allow for easy and extremely cost efficient connection of the power supply to several VariTrans A 21000 or other Knick products in 6 mm housings.
  • Cost reduction with smaller enclosure More channels per meter DIN rail thanks to space-saving 6 mm housing and closely packed mounting
  • Long service life Extremely low failure rate  (MTBF of 280 years) due to reduced self-heating
  • High accuracy and temperature stability Gain error 0.2 % and temperature coefficient 0.01 %/K
  • Calibrated range selection without complicated readjustments
  • Easy configuration DIP switch accessible from outside
  • Adjustable or fixed-range models
  • International use UL approvals for US and Canada
  • 5-year warranty

The VariTrans A 21000 isolates, transmits and converts 0 to 20/4 to 20 mA and 0 to 10 V with a high level of accuracy. In spite of its modular housing being only 6 mm wide, the new VariTrans isolation amplifier provides maximum protection of personnel and equipment through protective separation up to a working voltage of 300 V conforming to EN 61140. The test voltage is 2.5 kV AC. It can be supplied with either 24 V DC or 230 V AC.  




Catalog Excerpts

Catalog Excerpt - VariTrans A 21000

Catalog Excerpt (en)

370 |  VariTrans A 21000
Product Description | Specifications | Product Range
PDF (file size: 0.9 MB)


Manual - VariTrans A 21000

Manual (en)

375 |  A21000
PDF (file size: 0.2 MB)
Manual - VariTrans A 21000

Manual (en)

13391 |  ZU 0677 (Power terminal block)
PDF (file size: 0.22 MB)

Certificates / Approvals

EU Declaration of Conformity - VariTrans A 21000

EU Declaration of Conformity (en)

11493 |  Series VariTrans A 21000 P0
Document No. EU210121A | 2021-01-21  
PDF (file size: 0.19 MB)