Thursday, December 15, 2011

Water Monitors in Action

Thieves, vandalism. . .and thousands of irate phone calls. All in a day (or two’s) work for the municipal water department in the South African province of Pietermaritzburg. As this story details, a water outage a few weeks ago led to a bit of detective work, lots of walking, a night robbery, and, ultimately, a happy ending for a dried-up city and a few workers. And it all started with telemetry.
The first sign of a problem – even before citizens began complaining about a lack of running water – was detected at a central station connected to the system of water monitors in place throughout the city’s reservoirs and pipelines. Since municipal monitoring equipment is a specialty of ours here at Devar, this prelude to what followed is what caught our eye. As the water superintendent and other workers set out to discover the cause of the problem, a remarkable convergence of science and intuition allowed the chief to determine just what was going on, and where it was happening.
State-of-the-art monitoring equipment is often indispensable, and at the least, a key supporting element of any water system. But 30 years of human experience can’t be replicated by a machine, and that’s what the superintendant drew upon when his ears told him that the water flowing through the pipes just didn’t sound right. For all the talk of real-time monitoring and instant fixes, there’s no method more direct than just listening, if you can.
For the full story, be sure to read the article. It’s quite a tale, and – spoiler alert – the water does get turned back on in the end. For answers to any further questions about water monitoring and telemetry, contact Devar today!

Tuesday, December 6, 2011

Why and How? A Discussion of Loop Powered Indicators

When selecting a signal indicator, “loop powered” is a phrase that you may come across often. While extremely useful, it’s not always clear to our customers what, exactly, this technology consists of – and how it can help them. This is a very basic explanation of the theory behind, and the purpose of, loop powered indicators.

The most important thing to understand about loop power (or “current loop”), is that it helps maintain the accuracy of signal readings when the distance between a sensor and the monitor is very long. This is because, traditionally, a sensor will transmit information as electrical voltage. Voltage can be lost due to resistance during transmission, resulting in an inaccurately low reading by the monitor. Loop powered indicators solve this problem by converting voltage to electrical current, which is, by definition, the movement of electrons from one point to another. Electrons are much less likely to be lost in transmission than voltage.

So, a loop powered indicator converts a unit reading to a voltage, which is in turn converted to a proportional current figure between 4mA and 20mA (the meaning of the typical 4-20mA current loop). This is converted back to a voltage on the monitor device, either appearing as a display or being processed as a data reading.

For greater detail on the current loop process, see Current Loop.

Monday, November 28, 2011

Which Alarm is Right?

It can be daunting to choose the correct alarm or annunciator for your monitoring and control systems. There are seemingly endless options, which can get overwhelming. Below, we’ve listed five tips to organize your needs and simplify your selection process.
  • What Will the Alarm Be Measuring?  Options include temperature, voltage, and current. Select whichever input is critical to the application.
  • How Will the Signal Be Measured?  Alarms can be set to trip when a signal reaches a certain percentage of the setting, say 75%, or when it reaches a set amount in engineering units, like 120V, for example.
  • What Type of Display Do You Need?  Some alarms feature LED status indicators, which show whether or not the signal has exceeded the set point. Some alarms feature full LED displays for active, real-time monitoring of reading levels. Determine whether you need constant level displays or simply “on” or “off” readings.
  • What Type of Housing Do You Need?  The environment where the alarm will be installed is the most important feature in determining this. We generally feature NEMA housings, with an option for NEMA explosion proof housings, if the nature of the facility dictates that requirement.
  • How Will the Alarm Be Mounted?  All facilities are configured differently, and alarms have options to reflect that. Locate the safest and most convenient place to mount the alarm, and choose from options including Wall/Surface Mount, Rail Mount, and Pipe Mount.
At Devar, we’re always ready to help with product selection, and we hope that this list provides a good primer to get you started on the process. Use our Contact Us link for any further questions.

Monday, November 21, 2011

After the Storm: New York Waterways and Monitoring Systems

Several weeks after Hurricane Irene’s path up the East Coast, many water sources in New York State remained affected by flooding and swollen bodies of water, says this article.  Municipal water monitoring applications like this one are among the most important uses of telemetry and other data reading and transmitting devices. Early in the article, an official speaks about the “turbidity” of the water. Turbidity refers to the level of impurities in water and other fluids, and cannot usually be gauged by the naked eye.

Monitoring systems like those used by the New York Department of Environmental Protection are critically important to public health. In this case, monitoring systems allowed officials to determine that turbidity was improving but was still at unsafe levels, enabling state health agencies and water providers to inform their customers to boil water before drinking or using. Impurities can range from bacteria to chemicals and beyond, none of which can be safely ingested. The use of advanced monitoring systems here prevented illness and public health problems beyond the damage initially caused by the storm, a service application we couldn’t be happier to be part of.

Monday, November 14, 2011

Close to Home, A Quality Assurance

Some of our favorite aspects of working here at Devar Inc. are the longstanding relationships we’ve formed with so many of our customers.  Our commitment to our instrumentation and monitoring products, to safety, and to our customers is readily apparent, and is a big part of why our partners continue to work with us.  Our manufacturing facility bears the hallmarks of a company that truly cares about what we do, and the people we work with.  Our experienced and passionate staff, from the front office to the engineers on our manufacturing floor, are all united in one pursuit: quality in the production of our control and monitoring products.

We will often receive inquiries about our products where the bottom line is always price, no matter what.  While our facility doesn’t offer the bargain-basement pricing of some overseas facilities and importers, we do offer the top-of-the-line service and product quality that those companies can’t reproduce.  Our people make the difference, and we’re always happy to point to our facility right here in Bridgeport, CT as one of the top factors behind our success.  Whether you’re one of Devar’s longstanding partners, or just interested in what we do here, we welcome you to our new blog and look forward to the next time we work together.

Monday, November 7, 2011

Scientific and Medical Telemetry: Uses for the Greater Good

Telemetry, or remote monitoring equipment, is used in industries ranging from municipal water to environmental protection. We came across two interesting articles recently that described some of the more rewarding applications of telemetry equipment, and thought that we’d share with our readers.  This piece discusses telemetry and conservation, helping the overseas UK Environment Agency track endangered eels attempting safe passage to fresh water. The new telemetry system there allows scientists to gauge the success of an “eel pass” device installed to aid in this process.

We also found this news from Niagara Falls, NY, describing highly advanced telemetry equipment purchased by a hospital there. Direct access to patient data has never been easier, even remotely, and allows doctors to make quicker and more accurate diagnoses. One of the most interesting features is the ability to transmit data to a doctor’s smartphone or iPad. As technology continues to expand, keep following our blog here at Devar, Inc. for all the information.