Omega LDX-3A, LDX-3 User guide

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User’s Guide

LDX-3A

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It is the policy of OMEGA to comply with all worldwide safety and EMC/EMI regulations that
apply. OMEGAis 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, human applications.

M-1633/0905

LDX-3A

Section Title Page

4.6.2 Current Connections . . . . . . . . . . . . . . . . . 12

4.7 Using an EMC Cable Gland . . . . . . . . . . 13

5.0 Setting up the Transducer and LDX-3A . . . 14

5.1 Option Links Explained . . . . . . . . . . . . . 15

5.2 Basic Procedure . . . . . . . . . . . . . . . . 16

5.3 Sensitivity and the X2, X4,DIV2 Links . . . . 20

6.0 Half-Bridge Version . . . . . . . . . . . . . . . . 21

7.0 Specifications . . . . . . . . . . . . . . . . 22

7.1 Electrical . . . . . . . . . . . . . . . . . . . . . 22

7.2 Mechanical and Connections . . . . . . . . . 24

7.3 Environmental. . . . . . . . . . . . . . . . 24

7.4 Notes . . . . . . . . . . . . . . . . . . . . . .25

Section Title Page

1.0 Index . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.0 Safety Information . . . . . . . . . . . . . . . . 2

3.0 Introduction . . . . . . . . . . . . . . . . . . . . . 5

3.1 LDX-3A Enhancements . . . . . . . . . . . . 5

4.0 Installation . . . . . . . . .. . . . . . . . . . . . 6

4.1 Mounting . . . . . . . . . . . . . . . . . . . . . 6

4.2 Operational Environment . . . . . . . . . . . . . . 7

4.2.1 Residential, Commercial & Light Industrial

Environments . . . . . 7

4.2.2 Industrial Environments . . . . . . . . . . . . 7

4.3 Electrical Connections . . . . . . . . . . . . . . . 8

4.4 Connecting the Transducer . . . . . . . . . . . . . 9

4.5 Mains Power Supply . . . . . . . . . . . . . . 10

4.6 Connecting the Signal Out . . . . . . . . . 11

4.6.1 Voltage Connections . . . . . . . . . . . . . . . . .11

LDX-3A

1.0: Index

1

M-1633/0905

Terms in this Manual

WARNING statements identify conditions or practices

that could result in personal injury or loss of life.

CAUTION statements identify conditions or practices
that could result in damage to the equipment or other
property.

Symbols in this manual

This symbol indicates where applicable
cautionary or other information is to be found.

WARNINGS:
Do not operate in explosive atmosphere

To avoid explosion, do not operate this equipment in
an explosive atmosphere.

Installation Environment

The power supply unit is for indoor use only. It should
not be mounted where ingress of fluids is possible.

Safety Critical Environments

This equipment is not intended for use in a safety
critical environment.

Power Source

Apply no more than 264VAC between mains supply
pins and ground.

LDX-3A

2.0: Safety Information

2

M-1633/0905

LDX-3A

2.0: Safety Information

3

M-1633/0905

Service Safety

Safety Compliance Statement

LDX-3A is designed as Safety Class 2 apparatus with functional ground to comply with IEC 61010-1. The power supply
unit is marked as compliant with EN60950-1, but when as part of the LDX-3A assembly and installed by qualified
personnel according to these user instructions, then IEC 61010-1 compliance can be achieved.

This equipment has been designed and tested to meet the requirements of the Low Voltage Directive (73/23/EEC 1997)
and has been supplied in a safe condition. This manual contains information and warnings that must be followed by the
user to ensure safe operation and to maintain the apparatus in a safe condition.

Notes
Ground Connection

This equipment is supplied with a mains ground connection. This is a functional ground only. Loss of ground connection
may result in an AC voltage between accessible parts of the LDX-3A and reference earth. The voltage, current or charge
is at a safe level.

The power supply unit contains no user serviceable parts

This equipment must be returned to your dealer for all servicing and repair.

LDX-3A

2.0: Safety Information

4

M-1633/0905

CAUTION:
Electrostatic Discharge

This equipment is susceptible to ESD (Electrostatic Discharge) when being installed or adjusted, or whenever the case
cover is removed. To prevent ESD related damage, handle the conditioning electronics by its case and do not touch the
connector pins. During installation, follow the guidelines below.

- Ensure all power supplies are turned off.

- If possible, wear an ESD strap connected to ground. If this is not possible, discharge yourself by touching a
metal part of the equipment into which the conditioning electronics is being installed.

- Connect the transducer and power supplies with the power switched off.

- Ensure any tools used are discharged by contacting them against a metal part of the equipment into which the
conditioning electronics is being installed.

- During setting up of the conditioning electronics, make link configuration changes with the power supply turned off.

Avoid touching any other components.

- Make the final gain and offset potentiometer adjustments, with power applied, using an appropriate potentiometer
adjustment tool or a small insulated screwdriver.

CAUTION:
Fuse Rating

The LDX-3A power supply unit does not need a fuse for safe operation. However, wiring to the LDX-3Apower supply
unit may need to be fused. If the mains lead supplied with your LDX-3A has a fuse incorporated into the plug, then a
fuse of the same type and value should replace it. Otherwise, fusing and wiring to the LDX-3A must be performed in
accordance with local safety regulations. Refer wiring and fuse replacement to qualified personnel.

The LDX-3A is a development of the original LDX-3A. It is a compact conditioning module powered from an external
power supply unit. Adjustable gain and zero controls are provided for use with the complete range of Omega LVDT and
half-bridge transducers.* The unit is of robust construction, housed in a die cast metal box providing a substantial
degree of mechanical protection.
The LDX-3A uses a universal mains input power supply and provides an output of up to ±10V and ±20mA.

The LDX-3A has the following features.

- Wide gain range, allowing ALL Omega transducers to be connected without the need for attenuation resistors.

- Up to ±10V dc and ±20mA are available for all gain settings.

- Fixed and variable offsets make setting of uni-polar output easier.

- Gain and offset adjustment are fully independent.

- Selectable transducer excitation frequency.

- Selectable transducer load resistances.

- Selection between forward and reverse connection.

- Fully CE compliant.

- Half-bridge transducers can be accommodated with simple plug wiring changes.*

*For half-bridge only variant see section 6.0.

LDX-3A

3.0: Introduction

5

M-1633/0905

3.1: LDX-3A Enhancements

LDX-3A

4.0: Installation

6

M-1633/0905

The LDX-3A may be mounted in a variety of ways and in any attitude. Ensure that there is enough space for the cover
to be removed to allow for internal adjustments. Space should also be allowed for the transducer connector, EMC
glands (if fitted) and cabling. It is recommended that the LDX-3A case be connected to earth or chassis. This earth
connection is not a safety earth, but is part of the overall electrical screening scheme.

The power supply may be mounted in any position. The power supply is for indoor use only and must be protected from
fluids. Ensure that the power supply can be disconnected from the mains. This can be by removing the plug from the
power supply itself, or by disconnection from the mains source. Also ensure that the mains lead cannot be accidentally
disconnected.

4.1: Mounting

Underside Mounting Top-Side Mounting

Note: If replacing
LDX-3A MKI a
retrofit mounting
kit is available if
repositioning holes
is not possible.

This section discusses the type of installation required depending on the electrical environment.

Typically, this will be an office, laboratory or industrial environment where there is no equipment likely to produce high
levels of electrical interference, such as welders or machine tools.

Connections may be made using twisted, unscreened wire. This is a cost effective option and will give good
performance in this environment.

Standard equipment wire such as 7/0.2 (24AWG) can be twisted together as required. Standard data cable such as
generic CAT5 UTP will also give good performance.

Typically, this will be an industrial environment where there is equipment likely to produce high levels of electrical
interference, such as welders, machine tools, cutting and stamping machines.

Connections should be made using screened cable. Braided or foil screened cables may be used. The cable screen
should be connected to the LDX-3A case at cable entry point. The case of the LDX-3A should be connected to a local
ground. An EMC cable gland is recommended. This is supplied with the LDX-3A.

When selecting the type or wire or cable to be used, consider the following parameters:

- Screening.

- Conductor size (resistance).

- Mechanical aspects such as flexibility and robustness.

This is not a complete list. Installations may require other special cable characteristics.

M-1633/0905

4.2: Operational Environment

LDX-3A

7

4.0: Installation (continued)

4.2.1: Residential, Commercial and Light Industrial Environments

4.2.2: Industrial Environments

The LDX-3A requires three connections.

1. Transducer

2. Mains power supply.

3. Output signal, voltage or current.
A small hole should be made in the grommet prior to passing the wires through. If a screened cable is to be used, an

EMC cable gland is recommended.
For best performance in electrically noisy environments, the case of the LDX-3A should be connected to a local earth.

This can be achieved via the mounting bracket. This earth connection is not a safety earth, but is part of the overall
electrical screening scheme.

The wiring layout arrangements are similar for LDX-3A fitted with EMC glands and screened cable.

0V +VE

V OUT 0V I OUT

COARSE GAIN

FINE GAIN

COARSE
OFFSET

-VE
+VE

5V

10V

FINE OFFSET

10K

2K

- -

¦

R

¦

|F|

- -

DIV 2

X2

X4

G BK W R B

OUTPUT

POWER

1 2 3 4 5 6 (7)

FREQ

LO

(ON)

HI

(OFF)

NULL

4.3: Electrical Connections

4.0: Installation (continued)

M-1633/0905

LDX-3A

LDX-3A

4.0: Installation (continued)

9

M-1633/0905

4.4: Connecting the Transducer

Transducers fitted with a 5-pin DIN plug are simply screwed into the case mounted socket. Transducers not fitted with a
plug should be wired to the plug supplied. For the half-bridge only variant see section 6.0.

LVDT Electrical Connections
Red and Blue Energising
Green and White Signal
Yellow Secondary Centre Tap

Red and White

In Phase for Inward
Displacement

Black Transducer Body Ground

Half-Bridge Electrical Connections
Red and Blue Energising
Yellow Signal

Red and Yellow

In Phase for Inward
Displacement

Black Transducer Body Ground

CORE

Blue

Yellow

Red

V

V

A

B

Centre Tap

V

O

CORE

Primary

Red

Blue

V

e

Green

Yellow

White

V

V

A

B

Centre Tap

V

O

Measured

Output

Red

Blue

Yellow

+

-

Case

Half-Bridge

Cable Screen

Black

Case

Plug view

into pins

Standard Half-Bridge Gauging Probe Plug Connections

Note 1: + indicates inward movement of the tip.
Note 2: The transducer body may be disconnected from the cable screen by
cutting the black wire inside the connector

4 2

1

3

5

LINK

Red

Blue

Yellow

+

-

Case

LVDT

Cable Screen

Black

Case

Plug view

into pins

Standard LVDT Gauging Probe Plug Connections

Note 1: + indicates inward movement of the tip.
Note 2: The transducer body may be disconnected from the cable screen by
cutting the black wire inside the connector

3

4

5

2

1

Green

White

10

The mains adaptor is pre-wired to the LDX-3A. This is a universal power adaptor, so no adjustments are required for
mains frequency or voltage. Please review safety statements and installation section.

WARNING:

Ensure that the local safety precautions are observed for installation of mains equipment.

4.0: Installation (continued)

4.5: Mains Power Supply

1.8m lead

Gktpodfg ggfdgjs dfofkg f sdreyot

Gktpodfg ggfdgjs dfofkg f sdreyot

LDX-3A

M-1633/0905

11

The output signal may be voltage or current.

4.0: Installation (continued)

4.6: Connecting the Signal Out

0VVout

Iout

Process Monitor

+

-

Voltage

Voltage Monitor

LDX-3A

M-1633/0905

4.6.1: Voltage Connections

Voltage is most easily be monitored using a variety of instrumentation such as voltmeters. Voltage drops along wires
contribute to measurement errors, so care must be taken when using long cable lengths (100m for example). High
impedance instruments are more prone to interference.

12

Current output requires the use of purposely designed current input instrumentation. Current output is more suitable for
transmitting over longer distances because current is not lost due to wiring resistance. Additionally, with a low
impedance, a current loop is less likely to pick up noise.

The total loop resistance (resistance of measuring equipment and wiring) must not exceed specification.
Note: The LDX-3A is not loop powered. A power supply must not be used in-line with the current output.

4.0: Installation (continued)

LDX-3A

M-1633/0905

4.6.2: Current Connections

Iout

Vout

0

V

Process Monitor

Current

+

-

Current Monitor

LDX-3A

4.0: Installation (continued)

13

M-1633/0905

To ensure the cable screen is properly connected to the LDX-3A case, an EMC cable gland should be used. This is
supplied as an extra. The diagrams below assume a single 4-way cable is being used. Remove the grommet and fit the
cable gland as shown below.

- Prepare cable as shown.

- Slide the Dome nut, sealing ring and plastic insert over cable.

- Fold and roll the screen back over itself to form a lump.

- Push cable into gland body followed by the plastic insert
(ensure anti-rotation slots engage), sealing ring and Dome nut.

- Ensure all components are properly seated before tightening

the dome nut.

10-15 mm

Screen

30 mm

125 mm

Rolled Back Screen

Dome

Nut

Sealing

Ring

Plastic

Insert

Gland

Body

Case Wall

Rotate Gland Body

to Tighten

4.7: Using an EMC Cable Gland

LDX-3A

5.0: Setting up the Transducer and LDX-3A

14

M-1633/0905

The LDX-3A may be set-up with output signals anywhere within a ±10 Vdc or ±20 mA range. Typical outputs are ±10
Vdc, ±5 Vdc, 0-10 Vdc and 4-20 mA. These procedures apply to voltage and current output.

Voltage and current output are available at the same time, although they cannot be individually adjusted. Either voltage
or current should be chosen as the calibration reference.

All outputs use 0V signal as the signal reference.
A list of standard link settings is available, see section 5.2.

CAUTION:

During installation and adjustment, the top of the enclosure has to be removed for access to user adjustments. At this
time, standard ESD handling precautions for electronic equipment should be followed.

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

15

M-1633/0905

The table below and subsequent diagrams explain the link functions and show the factory setting.

5.1: Option Links - Explained

Link ON Link PARKED

Link OFF

Link

Description

Options Standard Setting

Course Gain Sets the basic gain 1 link on Positron 1 to 6 Link ON Position 1
Fine Gain Adjustment between course gain ranges Potentiometer Adjustment Mid Position
Course Offset Shifts the output by a fixed amount Link ON -VE or +VE and Link ON 5V or 10V

No offset - Link Parked

No offset - Links Parked

Fine Offset Fine trim around any fixed offset Potentiometer Adjustment Mid Position
(7) Null Used during set-up to null output ON, OFF OFF
Freq. Selects transducer primary frequency Lo - ON, Hi - Parked Hi Freq. - Link Parked
Input Resistance Sets transducer secondary load 100kΩ Parked, 10kΩ - ON, 2kΩ - ON 100KΩ - Link Parked
Polarity (FR) Enables output signal direction change 2 Links across Forward or Reverse F Position - 2 Link ON
Input Gain Input Gain of x1, x2, x4 or divide 2 X1 - Parked, X2 - ON, X4 - ON, DIV2 - ON Link parked on X2

0V +VE

V OUT 0V I OUT

COARSE GAIN

FINE GAIN

COARSE
OFFSET

-VE
+VE

5V

10V

FINE OFFSET

10K

2K

- -

¦

R

¦

|F|

- -

DIV 2

X2

X4

G BK W R B

OUTPUT

POWER

1 2 3 4 5 6 (7)

FREQ

LO

(ON)

HI

(OFF)

NULL

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

16

M-1633/0905

5.2: Basic Procedure

To set-up the LDX-3A, some basic steps should be followed.
The following steps describe a typical setting procedure and applies to most applications. Other procedures may be

used as appropriate.

Zero

-5V +5V

Null

electronics

transducer

Null

Zero

transducer

electronics

Null

+5V0V +10V

electronics

transducer

Shift
zero

For a bi-polar output i.e. ±10 Vdc or ±20 mA, follow steps 1 to 3.
For a uni-polar output i.e. 0-10 V, 0-20 mA or 4-20mA, follow steps 1 to 4.

In either case, step 5 (final checks) should be followed on the completion of the set-up.

Step 1 Step 2 Step 3 Step 4 Step 5

V/V

±V
Hz

K

ΩΩ



Set-up LDX-

3A links

Align LDX-3A and

Transducer Null

Set LDX-3A and

Transducer Range

Final Checks

Add Offset
if Required

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

17

M-1633/0905

5.2: Basic Procedure

STEP 1 - Set-up LDX-3A Links

If the transducer characteristics are known, set the frequency and input resistance links as required. If the transducer
characteristics are not known, the standard link settings should be used.

If your transducer is known to be outside of the standard sensitivity range, the X2 or DIV2 links will have to be used.
See section 5.3.

STEP 2 - Align LDX-3A Null and Transducer Null

Any electrical offset in the LDX-3A is removed. The transducer position is adjusted so that transducer and LDX-3A nulls
are aligned.

Null the LDX-3A.

1. Put the Gain link on position (7) as shown. This allows any electronics offset in the

output stage to be removed.

2. Adjust the Fine Offset control to give as near to zero output as practical.

Null the transducer.

1. Replace the Gain link to the original position.

2. Adjust the position of the transducer to give as near to zero output as practical.

This is the centre of the mechanical range.

If the transducer cannot be centered for practical reasons an offset will remain within the system. There may be
noticeable interaction between Gain and Offset adjustment. This does not prevent the LDX-3A being set-up, however
several iterations may be required when adjusting Gain and Offset. Please contact your supplier if guidance is required.

1 2 3 4 5 6 (7)

FREQ

LO

(ON)

HI

(OFF)

NULL

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

18

M-1633/0905

STEP 3 - Setting Bi-Polar Full-scale Output

1. Move the transducer to the position where maximum LDX-3A output is required.

2. If the polarity of the output is wrong, move the Polarity (FR) links to the R position (see link diagram).

3. Move the RANGE link between 1 and 6 until the LDX-3A output is near the required value.

4. Adjust the Fine Gain control to give the required output.

5. Abi-polar output has now been set, proceed to step 5. If a uni-polar output is required, proceed to step 4.

Example: ±10Vdc is required from a ±1mm transducer. Set the transducer to the +1mm position and set the output to
10V.

If your transducer is known to be outside of the standard sensitivity range, the X2 or DIV2 links will have to be used.
See section 5.3.

5.2: Basic Procedure

10K

2K

- -

¦

R

¦

|F |

- -

DIV 2

X2

X4

10K

2K

- -

¦

R

¦

|F |

- -

DIV 2

X2

X4

Normal Output Polarity Reverse Output Polarity

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

19

M-1633/0905

STEP 4 - Setting Uni-polar Full-Scale Output (adding an offset)

1. Move the transducer to the null position. LDX-3A output will be 0V or 0mA.

2. Apply offset using the +VE, -VE, 5V and 10V links and then adjust the Fine Offset control to set the offset precisely.

3. Perform final checks, step 5.

Example: 0-10V is required for a ±1mm transducer. Set the transducer to give ±5V over the full range and then, with the
transducer at null, add +5V offset. Adjust the Fine Offset control to give 5V. When the transducer is moved to the +1mm
position, the output will be +10V.

Example: 4-20mA is required for a ±1mm transducer. Set the transducer to give ±8mAover the full range and then, with
the transducer at null, add +2.5V (approx. 5mA) offset. Adjust the Fine Offset control to give +12mA. When the
transducer is moved to the +1mm position, the output will be +20mA.

STEP 5 - Final Checks

Ensure that the calibration is correct by moving the transducer across the required mechanical range, checking
calibration points. Fine adjustment can be made if required.

It may only be possible to set the output accurately at the two calibration points. This is due to non-linearity within the
transducer.

5.2: Basic Procedure

LDX-3A

5.0: Setting up the Transducer and LDX-3A (continued)

20

M-1633/0905

5.3: Transducer Sensitivity and the X2, X4, DIV2 Link

The LDX-3A compensates for changes in primary signal amplitude by producing an internal error signal that is the ratio
between the primary and secondary signals. If the transducer output signal is too high or too low, errors may occur that
can degrade the performance of the LDX-3A / transducer combination. For these transducers, the X2, X4 or DIV2 input
gain link must be used.

Transducer Full Range Output

In general, transducer sensitivity is quoted as mV/V/mm
Where: mV is the output of the transducer

V is the primary voltage
mm is the mechanical position of the transducer from null (usually mid mechanical range).

To get the transducer Full Range Output, multiply all three together.
Example: GP011-1 sensitivity is 210 mV/V/mm

GP911-1 range is ±1 mm
LDX-3A primary voltage 3V

Transducer Full Range Output = 210 x 3 x 1 = 630 mV (0.63V)

Set the X2, X4, DIV2 link as shown in the table below.

Transducer Full Range Output Input Gain Link Setting

400mV FR to 2500mV FR Standard Range - Link Parked on X2
2500mV FR to 5000mV FR High Transducer Output - Link ON DIV2
150mV FR to 400mV FR Low Transducer Output - Link ON X2
55mV FR to 150mV FR Very Low Transducer Output - Link ON X4

21

6.0: Half-Bridge only Variant

This is a Half-Bridge optimised variant of the standard product. The excitation frequency is higher (see specification) and
the transducer input connector is wired to accept half-bridge transducers with standard connections.

6.1: Connecting the transducer

The 5-pin DIN plug is screwed into the case mounted socket. Transducers not fitted with a plug should be wired to the
plug supplied. LVDT transducers cannot be connected to this input.

6.2: Setting up the Half-Bridge Transducer

The setting up procedure is the same as LVDT transducers. See section 5. The sensitivity of half-bridge transducers is
generally lower than for LVDT types, the x2 and x4 gain position may have to be used.

Red

Blue

Yellow

+

-

Case

Half-Bridge

Cable Screen

Black

Case

Plug view

into pins

Standard Half-Bridge Gauging Probe Plug Connections

Note 1: + indicates inward movement of the tip.
Note 2: The transducer body may be disconnected from the cable screen by
cutting the black wire inside the connector

4

1

2

5

3

CORE

Blue

Yellow

Red

V

V

A

B

Centre Tap

V

O

Half-Bridge Electrical Connections
Red and Blue Energising
Yellow Signal
Red and Yellow In Phase for Inward Displacement
Black Transducer Body Ground

LDX-3A

M-1633/0905

7.0: Specifications

LDX-3A

22

M-1633/0905

7.1: Electrical

Specifications are for the LDX-3Aonly. Effects due to transducers are not included. Output is set to ±10Vdc into a 1kΩ
load, unless specified differently. FRO means ‘Full Range Output’.

Parameter Value Comments
Power Supply

Mains Voltage 90 to 264 Vac
AC Input Frequency 47 to 86 Hz
AC Input Current 0.25 A(120 Vac), 0.1 A (250 Vac)

Transducer Excitation

Energising Voltage 3Vrms nominal see note 1
Energising Frequency 2.5kHz (Lo) or 5kHz (Hi) nominal

10kHz (Lo) or 13kHz (Hi)

link selectable
Half-Bridge version only

Energising Current 30mA max.

Transducer Signal Input

Input Signal Range Standard 400 to 2500mV FR 6 gain ranges (applies to LVDT only)

Special

DIV2 2500 to 500mV FR
x2 150 to 400mV FR
x4 55 to 150mV FR

see note 2

Input Load Resistance 2, 10, 10kΩ link selectable
Options Forward and Reverse

LVDT Input
Half-Bridge Input

link selectable
standard
special plug wiring or half-bridge version only

LDX-3A

7.0: Specifications (continued)

23

M-1633/0905

7.1: Electrical

Parameter Parameter Comments
Signal Output

Output Voltage Range

Up to ±10Vdc into 1kΩ min

see notes 3 and 4
Output Residual Noise <1 mV rms
Output Current

Up to ±20mA into 150Ω load

see note 5

Output Offset Coarse ±5Vdc (approx 10mA) fixed link selectable

±10Vdc (approx 10mA) fixed link selectable

Fine ±2.8Vdc (approx 5.6mA) Variable (adds to fixed offsets)

Temperature Coefficient Gain <0.01% FRO/°C
Temperature Coefficient Offset <0.01% FRO/°C
Warm-Up 15 minutes recommended
Linearity <0.1% FRO
Bandwidth (-3dB) 500Hz typical

Protection (see note 6)

Inputs and Outputs

Short circuit protected
Transient and ESD Protected

Certification (see note 7)

Immunity BS EN61000-6-2:2001 Immunity for Industrial Environments
Emissions BS EN61000-6-3:2001

Emission for Residential, commercial and light-industrial environments

Power Supply Safety Approvals

TUV EN60950, CE, CSA22.2, UL1950

Overall Safety Approval Compatible with IEC 61010-1 See note 8

LDX-3A

7.0: Specifications (continued)

24

M-1633/0905

7.2: Mechanical and Connections

7.3: Environmental

Parameter Value Comments

Operating Temperature Range 0 - 60°C see note 9
Storage Temperature Range -20 - 85°C
IP Rating IP40

Parameter Value Comments

Transducer 5-pin circular DIN
Power Supply Cable Length 1.8m maximum, fixed length Adaptor to LDX-3A case
Mains Connector IEC320 C14 C13 Mains lead supplied as required
Output Signal Internal terminal block
Enclosure Size 120 x 65 x 40 mm excluding connectors (See note 10)

Weight 300g approximately
Material Die-cast Zinc Alloy (painted)

Power Supply Size 65 x 49 x 33 mm

Weight 120g approximately

LDX-3A

7.0: Specifications (continued)

25

M-1633/0905

7.4: Notes

1. Primary voltage absolute value and drift are not specified. The LDX-3Auses ratiometric techniques to compensate for
primary voltage drift.

2. The way in which the LDX-3A functions means a special configuration must be used for transducers outside of the

standard range. This is selectable by links. The majority of Omega LVDT transducers are within the standard range.
The user manual provides details of the selection criteria.

3. LDX-3A can drive into a 1 kΩ load but this offers no advantage. 10-100 kΩ is recommended.

4. Output voltage range can be adjusted as required anywhere within this range by using a combination of gain and
offset, for example, ±10Vdc, ±5Vdc, 0-5Vdc, 0-10Vdc, 4-20mA. See user manual for adjustment method.

5. Current output may be used at the same time as voltage output. Calibration of voltage and current cannot be
individually adjusted.

6. Protection applies to the product when fully installed according to the user manual. During installation the top of the

enclosure has to be removed for access to user adjustments. At this time standard ESD handling precautions for
electronic equipment should be followed.

7. The LDX-3A complies with the toughest electrical emissions regulations. The power supply unit alone is only compliant

with BS EN61000-6-1:2001 (Immunity for residential, commercial and light-industrial environments). However, when
used as part of the LDX-3A assembly, the compliance levels are extended to BS EN61000-6-2:2001 (Immunity for
industrial environments). Compliance requires installation according to user manual. The flexibility of LDX-3Ameans it
can be installed in a variety of ways according to user requirements. Simple installations with short non-screened
cables will meet the lesser light-industrial immunity regulations. Heavy industrial installations, especially with longer
cables, will need more careful installation with screened cables.

LDX-3A

7.0: Specifications (continued)

26

M-1633/0905

7.4: Notes

8. The power supply unit alone is certified as described. When used as part of the LDX-3A and installed as described in
the user manual, then compliance with IEC 61010-1 can be achieved.

9. The LDX-3A itself has a 0 - 60°C specification. The power supply will function over a wider temperature range, but the

safety approval is only valid for 0 - 50°C.

10. The LDX-3A enclosure is smaller than the old model. This means that it will fit into all existing applications.

Mounting holes may need to be re-drilled. Extra mounting bars are available for situations where this is not
possible.

M-1633/0905

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’s 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 W

ARRANTY 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.
© Copyright 2004 OMEGA ENGINEERING, INC. All rights reserved. This

document may not be copied, photocopied, reproduced, translated, or reduced to
any electronic medium or machine-readable form, in whole or in part, without the
prior written consent of OMEGA ENGINEERING, INC.

LDX-3A

Where Do I Find Everything I Need for

Process Measurement and Control?

OMEGA…Of Course!

Shop online at www.omega.com

M-1633/0905

TEMPERATURE



Thermocouple, RTD & Thermistor Probes, Connectors,

Panels & Assemblies



Wire: Thermocouple, RTD & Thermistor



Calibrators & Ice Point References



Recorders, Controllers & Process Monitors



Infrared Pyrometers

PRESSURE, STRAIN AND FORCE



Transducers & Strain Gauges



Load Cells & Pressure Gauges



Displacement Transducers



Instrumentation & Accessories

FLOW/LEVEL



Rotameters, Gas Mass Flowmeters & Flow Computers



Air Velocity Indicators



Turbine/Paddlewheel Systems



Totalizers & Batch Controllers

pH/CONDUCTIVITY



pH Electrodes, Testers & Accessories



Benchtop/Laboratory Meters



Controllers, Calibrators, Simulators & Pumps



Industrial pH & Conductivity Equipment

DATA ACQUISITION



Data Acquisition & Engineering Software



Communications-Based Acquisition Systems



Plug-in Cards for Apple, IBM & Compatibles



Datalogging Systems



Recorders, Printers & Plotters

HEATERS



Heating Cable



Cartridge & Strip Heaters



Immersion & Band Heaters



Flexible Heaters



Laboratory Heaters

ENVIRONMENTAL
MONITORING AND CONTROL



Metering & Control Instrumentation



Refractometers



Pumps & Tubing



Air, Soil & Water Monitors



Industrial Water & Wastewater Treatment



pH, Conductivity & Dissolved Oxygen Instruments

LDX-3A