It’s a Recorder! No, It’s a Data Acquisition System! Actually, it’s Both

It used to be so simple. If you wanted to record something, you bought a circular or strip chart paper recorder. If there were multiple channels and not a lot of space available, you bought a multi-pen or multi-point recorder. If you happened to work for a utility company, once a year you made some salesman's day when you placed a huge order for chart paper.

By Staff March 1, 2003

Trends in Recorders

Paperless data acquisition

Fast sample rates

Network connectivity

Regulation-compliant

Digital data storage

Sidebars: Recorder users speak out

Product Section:

It used to be so simple. If you wanted to record something, you bought a circular or strip chart paper recorder. If there were multiple channels and not a lot of space available, you bought a multi-pen or multi-point recorder. If you happened to work for a utility company, once a year you made some salesman’s day when you placed a huge order for chart paper.

Of course if you needed to compare what happened in the last hour with what occurred last month and the month before, the solution wasn’t very ”friendly.” Even the wildest guess would probably not come close to estimating the amount of time spent unrolling and re-rolling strip charts over the years.

Come to think of it, maybe those ”simple solutions” weren’t that great after all.

DAQ in disguise

Today, the line between chart recorders-paper or paperless-and what’s become known as data acquisition systems (DAQs) is very blurry-that’s if the line exists at all.

A look in the 2002 Control Engineering Buyer’s Guide reveals 29 companies that offer paper chart recorders. However, many of those 29 companies also appear under the headings of paperless chart recorder, data acquisition, and datalogger.

Bottom-line, call it whatever you want, it’s really about creating historical records of data. (See CE , Feb. ’02, ” Users expect DAQ to also include analysis and control. ”)

Early versions of paperless recorders suffered wide acceptance because of missing or very limited security to protect against data tampering. Thus stored data records were not accepted by regulatory agencies, such as U.S. Food and Drug Administration (FDA, Rockville, MD) and the U.S. Environmental Protection Agency (EPA, Washington, DC).

Manufacturers have created DAQ systems that masquerade as paperless recorders because of secure software data encryption algorithms, cost-effective microprocessors and data storage media, and the FDA’s 21CFR Part 11 regulation covering electronic records.

Several DAQ/paperless recorder device manufacturers have chosen to focus their efforts on developing the collection and storage devices, and leveraging a popular graphical development application, such as National Instruments (NI, Austin, TX) LabView, as the user interface.

For example, a search for paperless recorders on the NI web site produces an impressive list of device drivers and preconfigured DAQ solutions for a variety of applications.

Storage available

Many single- and multi-pen paper recorders use analog electronics-thus inputs are continuously recorded. To improve data readability during periods of high-volume-data, many paper recorders include a selector switch for different chart speeds.

Because paperless recorders apply digital technology, continuous data collection isn’t possible. However, digital technology advances allow DAQ/paperless recorders to sample eight to ten samples per second. While that’s as good as ”continuous” for many applications, sampling at those speeds requires careful consideration of storage requirements.

For example, recording a single channel at 8 samples per second would fill a 1.44MB floppy disk in about a day. However, the same conditions would take over 72 days to fill a 100MB ZIP disk. When purchasing or upgrading a DAQ/paperless recorder, remember that storage is cheap; install lots, you won’t regret it.

Network aware

A major DAQ/paperless recorder trend is the need for network connectivity. Users want their DAQ/paperless recorders to download stored data to other network devices for analysis and reporting. Of course this brings up data integrity concerns.

Manufacturers targeting their products to address FDA and EPA regulations concerning electronic records are applying sophisticated data-encryption algorithms that permit examining data, but not changing it.

Not surprising in the growing world of personal communicators, DAQ/paperless recorder manufacturers aren’t confining network connectivity to hardwired networks. A few now offer remote access using wireless technologies.

Batch help

Anyone who’s tried to correlate paper or paperless chart records with start- and end-of-batch events will appreciate optional batch-related features manufacturers, like Eurotherm, have begun to offer.

Eurotherm’s batch process option permits naming up to six batch fields, each of which can be permanently written to the chart and electronically saved. This permits automatic or manual marking of data records with the start- and end-of-batch events, as well as providing means to record operator notations.

The result is easy retrieval of all recorded information related to a particular batch.

Based on information recorder manufacturers provided to Control Engineering ‘s article input request, it’s clear that DAQ/ paperless recorders represent the near-term future of the recorder market.

Sure, there’re still sales of paper-based recorders (mainly to power generation and wastewater industries), but the future is fairly clear. For the next few years, DAQ features will morph paperless recorders into DAQ systems. Longer term, DAQ systems will take on more control functions. In the end, there will only be control systems.

-Comments? E-mail dharrold@reedbusiness.com

Product Section: Recorders

For more manufacturers of these products, visit the Control Engineering Buyer’s Guide . For names of system integrators with experience in your industry, go to the Control Engineering .

Popular recorder gets tougher

Warminster, PA – ABB’s ScreenMaster 2000 (SM2000) paperless videographic recorder now includes a NEMA 4X/IP66 front panel allowing it to live in harsh environments. The SM2000 provides 12 recording channels and up to 12 universal analog inputs viewable in a variety of formats. Eight megabytes of on-board flash memory provide storage for up to 2.9-million samples. A 5.7-in. (14.5 cm) color display and analog resistive touchscreen provide a clear and friendly user interface.

www.abb.com ABB

Record data anywhere

Charlestown, RI – The design of Dewetron’s DEWE-600-REC hermetically sealed, high-impact data recorder allows users to record data in vehicles, on mountain tops, and just about anywhere else. About the size of a laptop computer, setup and operation of DEWE-600 is via 10-in. (25.4 cm), 800 x 600 pixel touchscreen display.

Capable of up to 16 ac or dc voltage inputs, continuous or triggered data are stored on the 30 GB internal disk drive. Data display formats available include oscilloscope, chart recorder, X-Y recorder, graphical meter, FFT analyzer, orbit graph for plotting vibration as a function of rotational position, and third-octave analysis.

www.dewamerica.com Dewetron

Access recorder data wirelessly

Leesburg, VA – With Bridge 5000 software loaded on an HP/Compaq IPAQ pocket PC or PDA, Eurotherm’s 5000 Series data acquisition products are capable of remote monitoring and control. Compliant with the FDA 21CFR Part 11 regulation, full security and traceability is included within Bridge 5000. The series utilizes 32-bit RISC processor technology to provide secure data storage. Besides traditional inputs, recording features of the 5000 Series include math, totalizers, counters, timers, and batch synchronization.

www.euortherm.com Eurotherm

Loggers meet FDA requirements

Stratford, CT – Dresser Instrument’s Ebro handheld data loggers provide a rugged, compact, lightweight means of ensuring medical, pharmaceutical, and food and beverage sterilization applications meet FDA regulations.

Validated by TÜV (Munich, Germany), Ebro data loggers conform to the FDA 21CFR Part 11 regulation for electronic signatures and records. Data analysis and viewing of data in a graphical or tabular format are via the Winlog 2000 software.

www.ebro.com Dresser Instruments

Paper charts with digital data storage

Madison, WI – Gould Instrument’s ViewGraf 7700 Series is a data acquisition system and high-speed chart recorder. With a push of the button on the 12.1-in. (30.7 cm) display, users can output data to a thermal array writer using 11-in. chart paper. ViewGraf 7700 Series supports up to 32 channels of thermocouple, accelerometer, strain gage, and several other general-purpose inputs. Data storage is provided by gigabytes of memory or ZIP drive. Ethernet network connectivity is also available.

www.gouldis.com Gould Instruments

USB provides plug-and-play DAQ

Tucson, AZ – Designed as an alternative to plug-in PC data acquisition boards, Intelligent Instrumentation’s UDAS leverages the plug-and-play characteristics popularized by universal serial bus. UDAS can be configured for 16 single-ended or 8 differential analog inputs, 16 TTL digital I/O channels, and one 32-bit high-speed counter. An optional analog-channel expander permits up to 256 single-ended, 128 differential channels, or a mix of each signal type. Power for UDAS is provided via the PC’s USB port.

www.instrument.com Intelligent Instrumentation

SV180 joins family of paperless solutions

Houston, TX – Thermo Electron’s SV180 data acquisition and monitoring system is designed with five, front-panel accessible expansion slots to accommodate combinations of analog and digital inputs and contact outputs cards. Data are scanned at less than 20 milliseconds per point and saved to 32 MB RAM, 3.5-in. floppy disk, 100 MB ZIP disk, or 2 GB ATA flash memory card. Network connectivity is available using Modbus protocol on RS-232, RS-485, or 10Base T Ethernet. The SV180’s ‘print screen’ function permits printing to any HP ink or laser jet printer via the parallel printer port.

www.thermo.com Thermo Electron

8 samples per second

Williston, VT – TTI’s Datagraph VX Series provides high-speed storage, a 5.6-in. (14.2 cm) color or 5-in. monochrome display. Two, four, or six direct universal inputs such as dc voltage, dc current (with external shunt resistor), nine different types of thermocouples, or six types of RTDs are available.

Data storage media include ZIP disk or flash memory card. Network connectivity is via RS-232, RS-485, or 10Base T Ethernet.

www.ttiglobal.com TTI

Panel-mounted thermal printer

Waltham, MA – Keltron’s TLC Series of thermal printers are 3.13 x 5.5 x 4.88 inch (8 x 14 x 12 cm); support 256 character ASCII; and offer a choice of fonts, chart speeds, and column widths. Power sources can range from 5 Vdc to 220 Vac. Supported serial communications are RS-232, RS-422, and RS-485. The front-panel membrane switch is dust and moisture-proof.

www.keltroncorp.com Keltron

Minitrend supports validation

Fort Washington, PA – Honeywell’s Minitrend paperless recorder meets regulatory agency conformance criteria for electronic signatures and records including restricted user access, data encryption, audit trail, unique electronic signatures, and inactivity logout. Assistance with regulatory installation and operational qualification is provided by Minitrend’s ”Validation Protocol Assembler,” a step-by-step recorder validation guide that includes preformatted documentation sign-off sheets.

www.honeywell.com/imc Honeywell

Recorder connects to fieldbus

Newnan, GA – Yokogawa’s DAQStation is a network enabled data acquisition station with ability to interface with FOUNDATION fieldbus devices. DAQStation also connects to SCADA/HMI software via its Ethernet interface and an OPC Server. DAQStation treats fieldbus and hardwired data alike, permitting each to be used as calculation variables.

www.yca.com Yokogawa

Recorder users speak out

According to Control Engineering’s 2002 Purchasing Study, paper and paperless recorder users remain loyal to the current manufacturer, with less than 1% indicating a willingness to change manufacturers. However, that doesn’t mean manufacturers can sit back and do nothing.

When asked to rank four reasons for changing to a different recordermanufacturer, the order of reasons are:

Better technology;

Better product integration;

Improved post-sale support; and

Lower purchase price.

Respondents also indicated their recorder purchasing plans for the next 12 months. Forty-eight percent expect purchases to remain the same, 34% expect purchases to decrease 5-10%, and 17% expect recorder purchases to increase 5-10%.