AC-line powered signal conditioner capable of operating most LVDTs and RVDTs.
Operating from 115 V or 220 V AC, 50-60 Hz, an LPC-2000 provides all circuitry required to operate an LVDT position sensor
and provide a high level, low noise analog DC output suitable for feeding analog or digital indicators, PLCs, and other system
indicating and control instrumentation or a 4-20 mA 3-wire current loop output.The LPC-2000 features user-selectable
excitation frequency and gain to function with sensors having widely different sensitivities. Connections are made via
recessed screw terminals at the top and bottom of the case, which mounts on DIN 1 or DIN 3 rail.

SPECIFICATIONS
SPECIFICATIONS
Power Input Voltage.....115 or 220 V AC, 50-60 Hz, 2.5 VA
LVDT Excitation Voltage................................3 V rms (Nom.)
LVDT Excitation Frequency..............3 kHz, 5 kHz or 10 kHz
LVDT Primary Impedance..............................200 Ohms (min.)
Output, Voltage Mode...............................±10 V DC @ 5 mA
Output,Current Mode...........4-20 mA sourcing, 300 Ohms max
Frequency Response.....................................-3 db at 250 Hz
Output Ripple.......................................................<10 mV rms
Output Impedance..............................................<10 Ohms
Nonlinearity....................................................±0.01% FSO
Operating Temp. Range.......0°F to +160°F(-18°C to +70°C)
Temp. Coeff. of Sens......0.01% FSO/°F (0.018% FSO/°C)
Controls..........................................................Zero and Span
Weight................................................7 ounces (200 grams)
MOUNTING
The LPC-2000 is designed to mount on the DIN rail mounting system, including DIN 1, 32mm X 15mm asymetrical, or DIN 3,
35mm X 7.5mm or 15mm symmetrical, rails as illustrated below.
15mm
32mm
15mm
35mm
DIN 1 Mounting
DIN 3 Mounting 3
Wiring Note: The wire colors and/or letters shown in the connection diagram apply only to Macro
Sensors standard AC LVDTs with 6 lead wires or 6-pin connectors. For LVDTs with other termina-
tions such as BB series gaging probes or SQ series heavy duty LVDTs, or for extension cables used
with LVDTs, consult the data sheet accompanying the LVDT or cable for the correct color codes or
terminal connections. Connect the LVDTs primary and secondaries to the signal conditioner accord-
ing to the wiring diagram, observing the magnetic polarity dots on the LVDT winding schematic.

Output
AC Power Input
LVDT
9
8
7
12
11
10
6
5
4
3
2
1
Top
Bottom
Green (C)

Blue (B)
Brown (F)
Yellow (E)
Black (D)
Red (A)
Output
Common
±10V DC
4-20
mA
AC
Line
AC
Line
AC Line
Ground.
Osc. Sync.
In/Out
Must be connected together, but
no connection to
LPC-2000 Necessary
Secondaries
Primary 4
CONNECTIONS
All wire connections to the LPC-2000 are through industry standard recessed screw clamp terminals that will accept
wire sizes from #28AWG to #12 AWG, either solid or stranded. Wires should be stripped 5/16 (8 mm) which will
provide the proper length of conductor without exposing any bare wire. Line power input wiring should utilize a
minimum size of #18AWG. Be sure to de-energize power line prior to making power connections.

INTERNAL ACCESS
It may be necessary to gain access to the inside of the LPC-2000 to adjust excitation frequency and/or gain jumpers.
De-energize line power. Using a knife blade, small screwdriver or similar tool, gently pry off the cover at points
indicated in figure below.

WARNING !
Dangerous voltages are present inside energized unit ! Be sure to de-energize unit prior
to removal of cover !

Division Of

5/16
(8 mm)
Strip
Wire 5
EXCITATION FREQUENCY SELECTION
The LPC-2000 has three user-selectable LVDT excitation frequencies. The desired frequency is normally set to match the
specifications and/or recommended operating frequency of the LVDT being used. As shipped from the factory, the unit is set
for 3 kHz excitation frequency which is common to many LVDTs. Frequency is changed by jumpers (shorting bars) on S1, S2
and S3. (see Figure 1). As supplied, a jumper is positioned across S1 as shown in Figure 1. To obtain 5 kHz, move the
jumper from S1 to S2. To obtain 10 kHz, move the jumper from S1 to S3.
WARNING!
Unit must be de -energized when
cover is removed. Dangerous voltages are present inside energized unit !

OUTPUT GAIN SELECTION
The LPC-2000 can operate with LVDTs having a wide range of sensitivities. Coarse gain selection is provided to permit
operation with most LVDTs. To set coarse gain, the full scale AC output of the LVDT being used must first be determined by
performing the following calculation:

Sensitivity in V olts/.001 X Excitation Voltage X Full Stroke in thousandths of an inch = Full Scale Output (V AC rms)

Example 1: ±0.050 Stroke LVDT
Sensitivity: 0.0065 V/.001 X 3 V rms X 50 (1/2 range in .001) = 0.975 V AC rms Full Scale LVDT Output

Example 2: ±1.000 Stroke LVDT
Sensitivity: 0.00065 V/.001 X 3 V rms X 1000 (1/2 range in .001) = 1.95 V AC rms Full Scale LVDT Output

Gain may be adjusted by placing jumpers S4, S5, S6, and S7 (shorting bars) in positions shown in the table below. Placing
jumpers as instructed will yield a ±10 V DC output at full scale LVDT displacement.



S 8
S 9
S 3
S 2
S 6
S 4
S 5
Zero
Control
Span
Control
S 1
S 7
LVDT Full Scale
Output AC Volts
S4
S5
S6
S7
0 - 0.3V
Open
Open
Open
Open
0.31V - 0.6V
Open
Jumper
Open
Open
0.61V - 2.5V
Open
Jumper
Open
Jumper
2.51V - 5.5V
Jumper
Open
Jumper
Open
GAIN SELECTION TABLE
Indicates Jumper positions as shipped from factory 6
MULTI-CHANNEL APPLICATIONS
A requirement may exist where multiple LPC-2000s are to be used and where units or wiring will be located in close proximity to
each other. The LPC-2000 can synchronize the oscillators of multiple units to prevent crosstalk, beating, and intermodulation
between units. To synchronize the oscillators, connect together terminal 5 on all units and connect together terminal 10 on all units.
These connections are in addition to the connections shown on page 3. One unit should be des ignated as the Master and the
balance of the units designated as Slaves. The Master units excitation frequency must be set in accordance with the instructions
given in the paragraph entitled Excitation Frequency Selection. On the Master unit, move jumper from S8 to S9. Slave units
must have a jumper (shorting bar) on S8 and all jumpers (shorting bars) must be removed f rom S1, S2, S3 and S9.


















CALIBRATION PROCEDURE
(Voltage Output)

To calibrate, remove LVDT secondary wire, usually Red or (A) from terminal 9. Insert temporary jumper between terminals 7 and 9
(this jumper will be removed after Zero adjustment). Apply AC power to unit and allow a 3-5 minute warm-up. Adjust the Zero
control until an output of 0 V DC is obtained betw een terminals 4 and 5. De-energize unit and remove temporary jumper from
between terminals 7 and 9. Re-connect secondary wire Red or (A) to terminal 9. Apply power to unit and move LVDT core or
body until an output of 0 V DC is obtained. This position is the true null of the sensor and the reference point from which
subsequent position measurements are made.

NOTE: If mechanical adjustment of the core or LVDT body is difficult or impossible, make this adjustment as close as
possible and then adjust the Zero control to obtain 0 V DC output. It is important that the LVDT be within 5% of its true null position
to ensure that full displacement is within the LVDTs rated linear range. Offsets of more than 5% may result in non-linear results at
or near full scale displacement.

Move the LVDT core to its full scale displacement and adjust the Span control to obtain a reading of 10 V DC. Outputs of less than
10 V DC may be obtained by adjusting the Span control (e.g. 5 V DC). If desired full scale output cannot be obtained by Span
control adjustment, reset gain jumpers (shorting bars) to next higher or lower setting as shown in GAIN SELECTION table on page
5 and then re-adjust Span control to obtain desired output. If it is necessary to reset gain jumpers. Be sure to de-energize unit
prior to removing cover.

Unit is now ready for normal operation.

CALIBRATION FOR 100% ZERO OFFSET
(Voltage Output)

100% zero offset allows the user to obtain a unipolar output over the full range of the LVDT.

Follow the instructions as described in the CALIBRATION PROCEDURE section for full scale use, but adjust the Span control for
half the desired full scale output (e.g. 5 V DC). Move the LVDT core to minus full scale displacement and adjust the Zero control
to obtain zero output. Move the LVDT core to plus full scale displacement and adjust the Span control for desired full scale output.
Repeat this procedure to ensure proper calibration.

Unit is now ready for unipolar operation.



9
8
7
12
11
10
Top
6
5
4
3
2
1
Bottom
9
8
7
12
11
10
Top
6
5
4
3
2
1
Bottom
9
8
7
12
11
10
Top
6
5
4
3
2
1
Bottom
Additional Connections For LPC-2000 Multi-channel
Master/Slave Configuration 7

CALIBRATION FOR 4 -20mA CURRENT LOOP OUTPUT
To calibrate unit for current output, make sure that current loop connections are made between Terminals 5 and 6. Remove
LVDT secondary wire, usually Red (A) from Terminal 9. Insert temporary jumper between termin