OMNIfacts eNewsletter
  News from Omniflex
EndUser Electronic Edition
2004-05-19 00:00:00


Omnifacts is published by Omniflex Pty Ltd. This newsletter is designed to inform and educate in the areas of monitoring and control.
This publication may be freely redistributed if copied in its entirety.  Portions of this newsletter may be
reprinted with permission

Inverting your plant signals
Ian Loudon

4 to 20mA in represents 20 to 4mA out?

Many analogue control applications require reverse action with respect to traditional plant instrumentation signals. e.g. 4 to 20mA in and 20 to 4mA out. Many control or safety systems use this technique. Interfacing to these devices on an analogue level can be difficult and indeed many specialized devices have been employed in this role. Using Omniterm TxB this application has been reduced to simplicity itself. Any signal input and be represented inverted at the output not just 4-20mA. This facility is just one of the many standard features on the TxB, so it's still the same stock item you would use for temperature signal conditioning  - no extra inventory! Try it out for yourself.


Isolation for Plant and Personnel Safety

Most Plant devices require interface signals to or from them and many have dangerous voltage levels for example variable speed drives which could easily be floating at several hundred volts relative to ground. Without isolation on these interfaces plant and personnel are exposed. The Omniterm Signal Isolators ensure trouble free installations and safety of plant personnel who can inadvertantly come into contact with these signals in other areas of the plant where there is no apparent indication of danger.


Omniterm Universal Special Function Module

Latest Release - The Omniterm Universal Special Function Module TFX

The OMNITERM TFX Special Function Module is ideal for those special applications where mathematical computations are required on your analogue signals. The TFX accepts two 1-5V or 4-20mA inputs and provides one universal output. The Omniterm TFX comes equipped with a wide selection of common mathematical functions. A user configurable 32 point linearisation table enables TxB to solve a wide range of signal processing applications such as belt slip monitoring, dual-redundant analogue inputs, ratio monitoring, rate-of-change monitoring etc.

  Select from a wide range of computation functions
  Fully configurable by the user
  Accepts two 4-20mA or 1-5Vdc inputs
  One universal 0-20mA / 0 to +-10V / 0 to +-10mA or
  Output isolation to 1500Vac

Solutions for:

  • Integration (Pulse Output)
  • Square Root Integration
  • Hi/Lo Follower
  • Multiply/Divide or Ratio
  • Deviation Monitoring - Absolute Value
  • Average Value
  • Linearisation (Square Root, Log 10, Ln, Sin, Cos Standard)
  • Rate Function - Ramp Limiter and Rate of change.
  • Track Functions - Track and Hold, Peak and Valley.

Last Month:

Last month we talked about several important topics including:

  • Inverting your plant signals
  • Isolation for Plant and Personnel Safety
  • Omniterm Universal Special Function Module

If you missed these or other key discussions,
you can find the back issues on the newsletters page of our website:


Subscribe to Omniflex News

Unsubscribe from Omniflex News

This publication may be freely redistributed if copied in its ENTIRETY.  Portions of this newsletter may be reprinted with permission.

(c) Copyright 2003 OMNIFLEX PTY LTD 

In this Issue
Inverting your plant signals
Isolation for Plant and Personnel Safety
Omniterm Universal Special Function Module
Last Month's Issue

"The Smallest Range of Products with the Largest Range of Applications"

Omniterm,  Make 35+ years of experience in Signal Conditioning part of your next  signal conditioning job.

Minimize Life cycle costs on Signal Conditioning

Omniterm one product fits all approach means less spares holding. Reduced specialist technical expertise required for field support, module replacement and field configuration.

High Reliability

Omniterms have been designed with high reliability applications in mind.

This product has been designed to meet the criteria of IEC61508 for SIL1 applications.

Special Application?

Talk to us we can help. Direct access to support engineers.

Get the DataSheet