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FACE Operations Support
Brookhaven monitors hardware component issues at all BNL-designed FACE sites.
We will list items here that appear to have broad applicability across
sites. If you have a hardware issue that may be of interest to other
FACE sites, please forward it to
Keith Lewin for inclusion below.
- Kurz Rotary Ramp Valve drive axle failure: In 1999, the
Aspen FACE experiment had an adapter shaft in one of
their Kurz valve drive mechanisms break in half. The adapter that
failed connects the drive clutch to the disk on the valve body that
contains the limit switch activation pin. BNL redesigned this
section of the drive assembly, using a thicker shaft made out of a
tougher alloy. To make the new shaft work in the existing valve,
we also machined new mating disks. The exact design on this disk
varies among valves, so kits specific to each site were distributed
to all FACE sites with installation instructions.
The reason we are listing this occurrence now is that there was another
shaft failure in 2005. It turned out that the site that experienced
this latest failure had never completed replacing these shafts in all of
their valves. This incident resulted in several days down time for
that treatment plot.
If you are
unsure whether your valves have been upgraded, see if you can locate any
of the shaft replacement kits or old shafts at your site. If you
have a replacement kit, you probably have a valve still using the old
shaft. The old shafts had a diameter of 0.25" (6.35 mm). The
equivalent diameter on the new shafts is 0.32" (8 mm). If you have
as many old shafts as you have valves, all of your valves have probably
been upgraded.
If you are still unsure whether your Kurz valves have been upgraded, you'll need to dismantle
the drive mechanism to find out. This isn't a complex task, but if done incorrectly, it can
damage the limit switches, which will also cause the valve to fail,
either immediately or in the near future. If you are not familiar
with disassembling the Kruz Rotary
Ramp Valve drive mechanism, contact Keith Lewin
or John Nagy for
assistance.
- LI-COR has discontinued the LI-62XX series CO2
analyzers: We have learned that LI-COR no longer builds the
LI-6252 and LI-6262 analyzers we recommend for use with the BNL FACE
control system and multi-port samplers. While almost any analyzer
with an analog voltage or current output can be used with these systems,
we have written drivers to allow the use of the digital communications
capability of the LI-6262 and LI-6252 models. Other analyzers,
even those from LI-COR, use different communications protocols. We
are presently testing drivers that will allow the use of the LIi-840
analyzer with the Multiport sampler. There are some issues with
the LI-840, such as a prolonged warm-up time, that makes this unit
poorly suited for use in a FACE control system, so we are still looking
for a replacement for that use. Please contact us with any
candidates, or sources for the LI-6252 or LI-6262 analyzers.
- LI-COR LI-62XX analyzers freeze after power dips: Many LI-COR
LI-6262 and LI-6252 analyzers used at FACE sites have been modified by
the factory or in the field to automatically restart after a power
outage. The Duke Forest FACE site has had several instances where
their LI-COR analyzers have failed to restart properly after momentary
power dips, requiring a manual power cycling of the unit, and possibly a
re-start of the FACE Control Program (FCP). To guard against this, we
suggest that all LI-62XX analyzers be powered through a 300 VA or larger
UPS.
- Transtector AC voltage surge suppressors provide best protection:
We have found that surge suppressors using silicone avalanche suppressor
diodes provide better protection than metal oxide varistor (MOV) based
units. The Transtector (www.transtector.com,
800-882-9110) SL Series has worked well protecting 120VAC equipment.
We are now testing the DPS Series, which has a better receptacle layout
for use with plug-in transformers. These suppressors do a superior job
protecting your instruments, but accomplish this by sacrificing
themselves. Transtector has a good warranty replacement policy,
but make sure to have a couple of spares on hand.
- Extend an Ethernet LAN out to the treatment plots: BNL has
extended the LAN at the Duke Forest FACE site from the control building
out to the treatment and control plots. We have found inexpensive
fiber to copper protocol converters, serial device servers, and wireless
access points that work in this environment. This LAN allows the
transmission of data from instruments located in the plots back to the
control building, without dedicating fiber optic pairs or channels on
the TC COM multiplexers for each instrument.
- Connecting field research sites to the Internet: We
have tested satellite, cellular, cable modem, wireless, and wired solutions for establishing
broadband Internet connections. Having a broadband connection
allows rapid transfer of data from the research site to remote users,
better access for remote monitoring of site operations, and easier
updating of computer operating systems, anti-virus programs and other
applications. With these technologies, essentially any field
research site can have an "always on" connection to the Internet.
BNL is interested in improving digital access to the FACE sites to
increase our ability to monitor site performance and troubleshoot
problems. Contact
Keith Lewin
if you want to explore improving your site's Internet access.
Critical Spares Stocked at Brookhaven
While some of the FACE system hardware is unique to each FACE
installation, many components are shared across all sites. BNL
maintains a stock of some of the more expensive or long lead time components
for use within the DOE/BER FACE Facility, and for loan to cooperating sites
using the BNL FACE design. We also try to keep track of the spares
inventory at other FACE sites and can often arrange a loan between two sites
on short notice. Contact Keith Lewin or
John Nagy if you have a
failure of a critical component and cannot obtain an immediate replacement.
The following is a listing of the items we usually have in stock. We are also interested in hearing
about any additional items that you would like us to have on hand as spares.
- 2" Kurz Rotary Ramp Valve
- Kurz insertion flow sensor
- Pitman gear motor for Kurz rotary ramp valve, Model # 400051
- Dutec digital controllers and modules
- Master TC COM serial fiber optic network multiplexer (model used in NC, WI, and TN)
- Client TC COM serial fiber optic network multiplexer (model used in NC, WI, and TN)
- MAC valve manifolds, 16 and 12 ports
- MAC 35 series 24VAC solenoid valves, Part# 35A-B00-DACA-2BA
- 120 to 24VAC/8A transformer
- Cosel 24VDC/2.1A power supply, Model #: K50AU-24
- BNL manufactured motor controller for Kurz Rotary Ramp Valve
- Dwyer high pressure switch, Model # APS-450
- Dwyer low pressure switch, Model # 1910-0
- FESTO Multiport tubing
connector and parts
- Transtector surge suppressor, Model # FSP4001
Are you running the latest FACE control software (FCP.exe)? The
current version is 6.74. For upgrades
please contact John Nagy.
Last Modified: February 1, 2008
FACE is a program of the
Office of
Biological and Environmental Research (BER) - U.S. Department of Energy. Please forward all questions
or comments about this site to:
Brookhaven FACE
Program
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