Humboldt FD-4A, Product Manual

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Notes/Caution
• Do not attempt to tighten screws on or disassemble the FD-4A unit, replace parts,
adjust the transformer core, make internal adjustments to the DTR-451 or perform
calibration routines other than those outlined above. Doing so may necessitate
factory recalibration and/or repair
• The FD-4A unit, LVDT and DTR-451 digital readout unit function inter- dependently.
All are serially numbered, individually calibrated and must remain together as a
matched set Do not shorten or lengthen the cable from the FD-4A to the DTR-451.
Components cannot be interchanged from one unit to another or ordered separately.
Note: Because each DTR-451 unit is calibrated to a specific FD-4A adapter do not
contact Humboldt Mfg. Co. directly if a problem develops with the readout unit. Repairs
must be directed through the factory so components can be recalibrated after the repair.
• Locate the DTR-451 unit in a protected area so water from the ductilometer bath
splashed onto it. Allow space around the unit for heat dissipation. Leave the
continually. A power conditioning unit is recommended especially if the apparatus is
an area where nearby industrial machinery creates spikes or surges in the power line.
Power fluctuations can affect the output to your recording devices.
• Do not immerse the FD-4A beyond the marking on the base. A one inch safety
margin is allowed to protect the LVDT. Although the LVDT coil is vacuum
impregnated with varnish and has a stainless steel casing, it is not a submersible
design. Permanent damage may result if brine comes in contact with it for any period
of time.
Note:
While the FD-4A adapter is immersed in a cold bath, water from the air may
condense on the upper portion of the body where the LVDT is located. High humidity
and/or condensation will not adversely affect the transformer or core.
• Securing the calibration stand to a workbench or table is required. The lightweight
phenolic base will tip forward in the higher weight ranges. Always use the cable and
weight holder supplied with the unit to hold your weights. Do not exceed 30 pounds
of weight for calibrating purposes.
• Do not clean the calibration stand with strong solvents such as methyl ethyl ketone.
Do not immerse the stand in solvent or water.
• Be careful when removing weights from the weight holder. The cable will untwist
somewhat as weights are applied and it must be allowed to twist back as weights are
removed. If all 30 pounds are removed suddenly, the cable may coil and/or kink.
Data Acquisition
To gain full advantage of the FD-4A apparatus, some type of data acquisition system is
required. Although tests can be run with a strip chant recorder or other output device,
computerized data acquisition has the advantage of being able to analyze, calculate,
compare, store and present data gathered from tests according to user requirements.
It is fast, accurate, and flexible.
Data acquisition cards and matching software packages which are compatible with
various personal computers and existing spreadsheet programs are available from
numerous sources. Many will work with the analog output from the DTR-451.
CAUTION: Keep hands, clothing and other objects away from moving parts when the
machine is in operation.