Electrical safety: When good grounds go bad

01/04/2007


With electrical equipment, there's often high confidence in good, solid, earth grounding for protection. In some situations unexpected "ground voltages" can cause serious instrumentation errors, not to mention safety concerns, warns Dataforth . Fortunately, there are ways to protect personnel and control components from unexpected ground or neutral-wire voltages.

Protection for power-hungry equipment includes circuit breakers with ground-fault detection built-in, surge protectors, lightning arrestors, uninterruptible power supplies with voltage regulation built-in, and other like devices.

Recommended protection for instrumentation includes isolating channels from one another and from ground. Isolating test and measurement systems and process control systems assures long, trouble-free, worry-free performance, Dataforth says.

The company's isolated signal conditioners, for instance, provide three-way isolation. The signal path, the electronics on the sensor side, and the electronics on the system side are all isolated from ground. Isolated signal conditioners provide excitation voltage and isolated excitation voltage for 4-20 mA loops, strain-gages, and LVDTs.

A Dataforth white paper covers common topologies used in industry to connect single-phase and three-phase systems, show how voltage distribution panels distribute working voltages and neutral and ground wire connections. Click here for the full Dataforth application note, "When Good Grounds Go Bad," available in PDF.

—Edited by Mark T. Hoske , Control Engineering editor in chief





No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Engineering Leaders Under 40; System integration improving packaging operation; Process sensing; PID velocity; Cybersecurity and functional safety
Mobile HMI; PID tuning tips; Mechatronics; Intelligent project management; Cybersecurity in Russia; Engineering education; Road to IANA
Save energy with automation; Process control system upgrades; Dispelling controll myths; Time-sensitive networking; Control system integration; Road to IANA
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Flexible offshore fire protection; Big Data's impact on operations; Bridging the skills gap; Identifying security risks
The digital oilfield: Utilizing Big Data can yield big savings; Virtualization a real solution; Tracking SIS performance
Getting to the bottom of subsea repairs: Older pipelines need more attention, and operators need a repair strategy; OTC preview; Offshore production difficult - and crucial
click me