[an error occurred while processing this directive]
 
Introduction
Limitations of Traditional Oscilloscopes
Management and Safety in the Workplace
Floating an Oscilloscope: A Definition
Safety Engineering Principles
Safety - A Shared Responsibility
Battery-Powered Oscilloscopes
Monolithic Isolation Amplifiers
Differential Management System
Isolated-Input Oscilloscopes
Conclusion
 PDF Available (1.2MB)
 

Floating Oscilloscope Measurements ... And Operator Protection

Safety Engineering Principles

Tektronix has adopted many safety principles in the design of their products. Of particular concern to making electrical and electronic measurements are these principles:


  • When the instrument is used properly, accessible parts shall not become hazardously live, even in the event of the single worst-case fault.
  • Electronic devices (those devices employing conduction in a vacuum, gas, or semiconductor) shall not be relied upon for providing operator protection from electric shock.
  • Products should not develop insidious hazards during proper operation (an insidious hazard is a hazard which can develop in a way as to be well established before becoming apparent).
  • The operator shall not need to defeat a protective system to make the measurement.

Safety - A Shared Responsibility

The operator and employer share in the responsibility of meeting these principles - through proper operation and measurement techniques.

WARNING

Never attempt to defeat the protective grounding system of your oscilloscope by using an isolation transformer (top) or disconnecting the ground connector on the power plug (bottom). Failure to follow safety warnings can result in serious injury or loss of life.



Table 1. Methods of Making "Floating" Measurements Using Tektronix Instrumentation
Meets Safety Engineering Principle Dynamic Range/Bandwidth Ease of Operation Common-Mode Voltage (Float) Differential Mode Voltage (Signal) Common-Mode Reject
Isolation Amplifiers
(A6907 and A6909)
X High Medium <850 Vrms <850 Vrms High
Active High Voltage Differential Probes
(P5200 Series)
X Medium High <2,200 Vrms <4,400 Vrms Medium
Differential Amplifiers
(P6135A)
X Medium (+) Medium (-) <353 Vrms <353 Vrms High
Battery Powered Oscilloscopes (TDS3000 Series) X
CAUTION!
Low High <30 Vrms
ONLY
<30 Vrms
ONLY
Low
Isolated Input Oscilloscopes (THS700 Series) X High High <600 Vrms <1,000 Vrms Low
Isolation Transformers WARNING! This Is An Unsafe And Dangerous Practice And Should Never Be Done!
Defeating Grounds WARNING! This Is An Unsafe And Dangerous Practice And Should Never Be Done!



Limitations of Traditional Oscilloscopes
Battery-Powered Oscilloscopes


- Top of Page

 PDF Available (1.2MB)

51W-10640-1, 11/1998, 09/10/2001

[an error occurred while processing this directive]