DCTH Series DC to DC LVDT Displacement Transducer

High resolution
Voltage / 4-20mA output
High cycle life
Stainless steel
High accuracy

How it Works - Dc LVDT
How it Works - 4 to 20mA LVDT
   Data sheet (271kb)
These transducers are for displacement / position measurement. They make an accurate position measurement of the movement of the armature (the sliding part) relative to the body of the displacement transducer.

This transducer uses the Linear Variable Differential Transformer (LVDT) principle which means that it is probably the most robust and reliable position sensor type available. The strength of the LVDT sensor's principle is that there is no electrical contact across the transducer position sensing element which for the user of the sensor means clean data, infinite resolution and a very long life.

Our DC to DC LVDT transducer has all of the benefits of the LVDT sensor principle with the added convenience of built-in LVDT electronics enabling a dc supply and dc output. As an option we can offer a 4-20mA 2 wire connection to the transducer on some models.

This series of displacement transducer is available as either an unguided, captive or spring return version.
Unguided version..
On our unguided LVDTs the armature assembly is a separate component, to make a measurement the user must guide the armature inside the body without touching the sides. Unguided position measurement transducers are appropriate where external guidance is available and give truly non-contact operation
DCTH100 to DCTH400
DCTH500 to DCTH8000
Type Range Linearity error (% F.S.) L X Total weight Armature weight TF Over-Travel
Inward over-travel
DCTH100 2.5mm <0.5/0.25/0.1 64mm 33mm 74g 1.4g 18mm 11.6mm
DCTH200 5mm <0.5/0.25/0.1 64mm 33mm 74g 1.8g 18mm 9.0mm
DCTH300 7.5mm <0.5/0.25/0.1 64mm 33mm 74g 1.8g 18mm 6.5mm
DCTH400 10mm <0.5/0.25 64mm 33mm 74g 1.9g 18mm 3.9mm
DCTH500 12.5mm <0.5/0.25/0.1 175mm 43mm 213g 17g 15mm 16mm
DCTH1000 25mm <0.5/0.25/0.1 203mm 69mm 270g 23g 15mm 22mm
DCTH2000 50mm <0.5/0.25/0.1 317mm 81mm 369g 37g 15mm 16mm
DCTH3000 75mm <0.5/0.25/0.1 430mm 119mm 497g 55g 15mm 29mm
DCTH4000 100mm <0.5/0.25/0.1 475mm 132mm 625g 71g 15mm 16mm
DCTH6000 150mm <0.5/0.25 666mm 183mm 852g 100g 15mm 16mm
DCTH8000 200mm <0.5/0.25 856mm 259mm 1.3kg 140g 29mm 27mm

Captive guided version..
Our captive guided displacement transducer has bearings to guide the armature inside the measurement sensor. Captive LVDTs are for position measurement applications where guidance may be poor and end bearings may be required.
A = 23mm
D1 = 20.6mm
TR = M5x0.8 / 11mm
TF = M5x0.8
Type Range Linearity error (% F.S.) L X D3 Total weight TF Over-Travel
Inward over-travel Outward over-travel
DCTH500C 12.5mm <0.5/0.25/0.1 194mm 38mm 4.75mm 340g 15mm 10mm 12mm
DCTH1000C 25mm <0.5/0.25/0.1 222mm 63mm 4.75mm 398g 15mm 13mm 10mm
DCTH2000C 50mm <0.5/0.25/0.1 336mm 76mm 4.75mm 511g 15mm 10mm 14mm
DCTH3000C 75mm <0.5/0.25/0.1 448mm 114mm 4.75mm 625g 15mm 24mm 15mm
DCTH4000C 100mm <0.5/0.25/0.1 494mm 127mm 4.75mm 767g 15mm 8mm 14mm
DCTH6000C 150mm <0.5/0.25 684mm 178mm 4.75mm 1.0kg 15mm 12mm 17mm
DCTH8000C 200mm <0.5/0.25 875mm 254mm 4.75mm 1.4kg 32mm 22mm 25mm
DCTH10000C 250mm <0.5/0.25 1067mm 305mm 4.75mm 1.7kg 27mm 34mm 35mm
DCTH15000C 375mm <0.5 1473mm 406mm 4.75mm 2.2kg 19mm 13mm 13mm
DCTH18500C 470mm <0.5 1740mm 508mm 6.00mm 2.6kg 27mm 5mm 33mm

Spring return version..
Our spring displacement transducer has bearings to guide the armature inside the measurement sensor and a spring which pushes the armature to the fully out position. Spring return LVDTs are appropriate where it is not possible to connect the transducer armature to the moving component being measured.
DCTH500A to DCTH3000A
Type Range Linearity error (% F.S.) L X Total weight Spring force (nom) Over-Travel
Spring force at X Spring rate Inward over-travel Outward over-travel
DCTH100AG 2.5mm <0.5/0.25/0.1 64mm 12mm 83g 1.0N 0.9N/cm 2.2mm 1.3mm
DCTH200AG 5mm <0.5/0.25/0.1 64mm 13mm 83g 1.0N 0.8N/cm 0.3mm 1.3mm
DCTH300AG 7.5mm <0.5/0.25/0.1 64mm 18mm 83g 1.5N 0.6N/cm 1.4mm 1.3mm
DCTH400AG 10mm <0.5/0.25 64mm 22mm 83g 1.8N 0.8N/cm 1.3mm 1.3mm
DCTH500A 12.5mm <0.5/0.25/0.1 182mm 38mm 227g 1.3N 0.2N/cm 1.0mm 13mm
DCTH1000A 25mm <0.5/0.25/0.1 210mm 63mm 284g 2.0N 0.3N/cm 3.0mm 10mm
DCTH2000A 50mm <0.5/0.25/0.1 324mm 75mm 398g 1.8N 0.2N/cm 8mm 14mm
DCTH3000A 75mm <0.5/0.25/0.1 436mm 114mm 511g 6.0N 0.4N/cm 15mm 15mm

Output details (outputs 1 and 2 selected using different connections)
Option code Note - position 0 +position
Standard Connection details Output 1 0V 5V 10V (+0% - 5%)
Standard Connection details Output 2 -5V (+0% - 5%) 0V +5V (+0% - 5%)
TM0627 Connection details Output 1 10V (+0% - 5%) 5V 0V
TM0627 Connection details Output 2 +5V (+0% - 5%) 0V -5V (+0% - 5%)
TM0321A Connection details >=12.5mm 4mA 12mA 20mA
TM0321B Connection details >=12.5mm 20mA 12mA 4mA

V output Supply voltage (dual) 12V to 20V dc, 30mA
Supply voltage (single, must be floating) 24V to 40V dc, 30mA
Change in output for change in supply 5mV/V
Output load 10kOhms
Output ripple 30mV (peak-to-peak)
Electrical output bandwidth 200Hz
Output impedance 2 Ohms
Operating temperature range -40C to 80C
4-20mA output (>=12.5mm)
Supply voltage 12V to 36V dc
Max loop resistance (Supply voltage-11) x 50 Ohms
Output ripple 50uA (peak-to-peak)
Electrical output bandwidth 200Hz
Operating temperature range -10C to 70C
Both outputs Temperature coefficient (zero) 0.01% F.S. /C (typical)
Temperature coefficient (span) 0.03% F.S. /C (typical)
Electrical termination 2m (integral cable) Longer available to order.

Options and accessories

Rod-end bearings for captive-guided position transducers
Alternative probe tips for LVDTs
Mounting block

All dimensions and specifications are nominal. www.rdpe.com/ex/dcth.htm 20150909
Due to our policy of on-going development, specifications may change without notice. Any modification may affect some or all of the specifications for our equipment.
USA & Canada
RDP Electrosense
2216 Pottstown Pike
Pottstown, PA 19465
Tel: 610-469-0850
Tel: 800-334-5838
Fax: 610-469-0852
Email: info@rdpe.com
Rest of the world
RDP Electronics Ltd
Grove Street, Heath Town
Wolverhampton, West Midlands, WV10 0PY
United Kingdom

Tel: +44 1902 457512
Fax: +44 1902 452000
Email: sales@rdpe.com
URL: www.rdpe.com