It is the policy of OMEGA to comply with all worldwide safety and EMC/EMI regulations that apply. OMEGA is constantly pursuing certification
of its products to the European New Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.
The information contained in this document is believed to be correct, but OMEGA Engineering, Inc. accepts
no liability for any errors it contains, and reserves the right to alter specifications without notice.
WARNING: These products are not designed for use in, and should not be used for, patient-connected applications.
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DESCRIPTION
The ST and HT range of high reliability L.V.D.T.’s are shielded from electrostatic and electromagnetic interference
by magnetic stainless steel casing and end plates.
Because the manufacturing process is fully understood and is of the highest standard, this results in the cores
being interchangeable with no specific orientation.
High output voltage over a large frequency range and large core to bore clearance are major features of this
L.V.D.T.
The design is splash proof, but may not be suitable for complete immersion.
INSTALLATION
L.V.D.T. transducers generally are a reliable and proven technology that is well established in all areas of
manufacturing and control industries. The majority of the associated problems experienced with their application
and use are totally avoidable, particularly if sufficient thought is given during the initial design stages of
equipment, to the positioning and clamping methods employed for these feedback elements.
L.V.D.T.’s being of inductive nature are susceptible to some degree to the influence of magnetic fields and
therefore should be positioned well away from electric motors, relays and permanent magnets, where this is not
possible then magnetic shielding should be considered as an alternative.
Clamping of the coil assembly should be carefully considered, some example methods are shown overleaf. Ideally
the body of the transducers should be clamped centrally in a pinch or yoke type clamp, manufactured from a low
conductivity, non-magnetic material, if this is not possible then the introduction of a non-metallic bush between
body and clamp is a preferred alternative.
Irrespective of clamping method care must be taken not to overtighten retaining screws as distortion of the body
may prove damaging to the integrity of the transducer and adversely effect the geometry of the installation.
If the L.V.D.T. is to be mounted on equipment subject to high ”g” then dependent on the direction of these forces,
it may be advantageous to consider end to end clamping in preference to over body clamping.
The magnetic core supplied with each transducer has been manufactured and heat treated to achieve the
optimum magnetic performance, any subsequent handling of the core which results in stress being imparted will
render the calibration void, this includes overtightening of the core during installation onto its carrier. Hand
tightening and retention by means of a suitable thread locking anaerobic retainer is the recomm ended procedure.
Figure 1 Examples of Clamping Methods
IF POSSIBLE CENTRALISE L.V.D.T.
NON-METALLIC SPLIT (TUFNOL)
BUSH FOR USE WITH METALLIC CLAMP
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Figure 2 Electrical Connections
Y
Y
PRIMARY
SECONDARY
Black
ellow/Black
Green
Blue
ellow/Red
Red
Connect Blue to Green or Black to Red for differential output.
Calibrated frequency,voltageload
2.5kHz3 volts rms100kΩ
Yellow/Red and Red are in phase for forward displacement (toward cable end).
Note: Fit ”Quad Balance” resistor if supplied, between Red/Blue or Black/Green, as directed, in order to optimise
linearity around null.
CARRIERS
A standard length carrier is available for each model of transducer, manufactured from 316 stainless steel and
incorporating an 6-40UNF x 0.39” (10mm) long male thread for attachment to the standard core and an M4 x
0.027” x 0.78” (0.7 x 20mm) or 6-40UNF male thread for attachment to the fixture.
CABLE
The standard termination is by 7/0.125 P.T.F.E. insulated flying leads, capable of withstanding the operating
temperature of the L.V.D.T.
Routing of cables should be kept as smooth as possible avoiding burrs, sharp edges and excessive cable loads.
ENVIRONMENTAL
STHT
ST(HT) Operating Temperature Range
ST(HT) Storage Temperature Range
-67°F/+302°F
(-55°C/+150°C)
-67°F/+302°F
(-55°C/+150°C)
–67°F/+392°F
(-55°C/+200°C)
–67°F/+392°F
(-55°C/+200°C)
Conditions of high humidity and vibration should be avoided.
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WARRANTY/DISCLAIMER
OMEGA ENGINEERING, INC. warrants this unit to be free of defects in materials and workmanship for a period
of 13 months from date of purchase. OMEGA Warranty adds an additional one (1) month grace period to the
normal one (1) year product warranty to cover handling and shipping time. This ensures that OMEGA’s
customers receive maximum coverage on each product.
If the unit malfunctions, it must be returned to the factory for evaluation. OMEGA’s Customer Service Department
will issue an Authorized Return (AR) number immediately upon phone or written request. Upon examination by
OMEGA, if the unit is found to be defective, it will be repaired or replaced at no charge. OMEGA’s WARRANTY
does not apply to defects resulting from any action of the purchaser, including but not limited to mishandling,
improper interfacing, operation outside of design limits, improper repair, or unauthorized modification. This
WARRANTY is VOID if the unit shows evidence of having been tampered with or shows evidence of having been
damaged as a result of excessive corrosion; or current, heat, moisture or vibration; improper specification;
misapplication; misuse or other operating conditions outside of OMEGA’s control. Components which wear are
not warranted, including but not limited to contact points, fuses, and triacs.
OMEGA is pleased to offer suggestions on the use of its various products. However, OMEGA neither
assumes responsibility for any omissions or errors nor assumes liability for any damages that result
from the use of its products in accordance with information provided by OMEGA, either verbal or written.
OMEGA warrants only that the parts manufactured by it will be as specified and free of defects. OMEGA
MAKES NO OTHER WARRANTIES OR REPRESENTATIONS OF ANY KIND WHATSOEVER, EXPRESS OR
IMPLIED, EXCEPT THAT OF TITLE, AND ALL IMPLIED WARRANTIES INCLUDING ANY WARRANTY OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED.
LIMITATION OF LIABILITY: The remedies of purchaser set forth herein are exclusive, and the total
liability of OMEGA with respect to this order, whether based on contract, warranty, negligence,
indemnification, strict liability or otherwise, shall not exceed the purchase price of the component upon
which liability is based. In no event shall OMEGA be liable for consequential, incidental or special
damages.
CONDITIONS: Equipment sold by OMEGA is not intended to be used, nor shall it be used: (1) as a “Basic
Component” under 10 CFR 21 (NRC), used in or with any nuclear installation or activity; or (2) in medical
applications or used on humans. Should any Product(s) be used in or with any nuclear installation or activity,
medical application, used on humans, or misused in any way, OMEGA assumes no responsibility as set forth in
our basic WARRANTY / DISCLAIMER language, and, additionally, purchaser will indemnify OMEGA and hold
OMEGA harmless from any liability or damage whatsoever arising out of the use of the Product(s) in such a
manner.
RETURN REQUESTS / INQUIRIES
Direct all warranty and repair requests/inquiries to the OMEGA Customer Service Department. BEFORE
RETURNING ANY PRODUCT(S) TO OMEGA, PURCHASER MUST OBTAIN AN AUTHORIZED RETURN (AR)
NUMBER FROM OMEGA’S CUSTOMER SERVICE DEPARTMENT (IN ORDER TO AVOID PROCESSING
DELAYS). The assigned AR number should then be marked on the outside of the return package and on any
correspondence.
The purchaser is responsible for shipping charges, freight, insurance and proper packaging to prevent breakage
in transit.
FOR WARRANTY RETURNS, please have the
following information available BEFORE contacting
OMEGA:
1. Purchase Order number under which the product
was PURCHASED,
2. Model and serial number of the product under
warranty, and
3. Repair instructions and/or specific problems
relative to the product.
FOR NON-WARRANTY REPAIRS, consult OMEGA for
current repair charges. Have the following information
available BEFORE contacting OMEGA:
1. Purchase Order number to cover the COST of the
repair,
2. Model and serial number of the product, and
3. Repair instructions and/or specific problems relative
to the product.
OMEGA’s policy is to make running changes, not model changes, whenever an improvement is possible.
This affords our customers the latest in technology and engineering.
OMEGA is a registered trademark of OMEGA ENGINEERING, INC.