Compact actuatorLegacy
Thomson WhisperTrak compact actuator
Quiet acme-screw DC actuator designed to medical electrical safety standards for patient handling and mobility products, up to 4,000 N; Thomson still publishes its product page in the legacy section.
Need this part, a replacement or a complete package? Our experienced UK engineering team helps you select, source and obtain the right products, with pricing, delivery coordination and after-sales support.
Thomson lists this series as legacy. We can help with spares for installed machines, a migration to the replacement, or an alternative. Find a replacement.
Pricing and availability
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Need Thomson parts, a replacement or a suitable alternative? Send us a part number, or tell us what the machine needs to do. Our UK engineers will come back with the right product, pricing, lead time and delivery, whether that is the original part, a checked alternative or a complete axis.
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Spec builder
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Select every part you need and answer the questions an applications engineer would ask. Our engineers use your specification to come back with the right products, pricing and lead times. You see your summary before we ask for any details.
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- 1Products
- 2Performance
- 3Environment
- 4Volumes
- 5Your spec
What are you specifying?
Select everything you need. A motor, drive and gearbox can be specified together as one axis.
Key specifications
| Ingress protection | IP67 |
|---|---|
| Temperature | -25–40 °C |
| Force (max) | 4,000 N |
| Stroke (max) | 500 mm |
| Linear speed (max) | 11 mm/s |
| Screw type | acme |
| Supply | 12, 24 Vdc |
| Duty | 10% max (90 s or 180 s max on-time) |
| Sizes | Wxx02: 2,000 N; 5.8 or 11.0 mm/s no load; strokes 100-500 mm, Wxx04: 4,000 N; 5.8 mm/s no load; strokes 100-500 mm |
Summarised in our own words from Regal Rexnord's published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1 · Source 2
Notes on this data
Status corrected discontinued -> legacy (2026-10-30): the WhisperTrak product page presents the range with no obsolete or replacement wording, but sits under /products/linear-actuators/legacy/ and Thomson's actuator training overview lists it under "Obsolete Actuators"; confirm availability per part number. Metric as printed (strokes 10-50 cm). Sound level below 45 dBA; IEC 60601-1 / AAMI ES60601-1 / CSA C22.2. Average life 10,000 cycles.
Specify Motion is not affiliated with Regal Rexnord. Thomson and WhisperTrak are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Thomson WhisperTrak replacement and alternative options
Use these supply-network options as a starting point for an engineering check. We can also help source the original Thomson part. Published series figures do not establish an exact-model or drop-in replacement: confirm ratings, fit, interfaces and approvals for your application.
Slim tubular 12/24 VDC actuators with the brushed motor and planetary gearbox in line with the tube, in diameters 16-55 mm, for pergolas, marine, medical and building automation.
| Published maximum | WhisperTrak | LA In-line Linear Actuators |
|---|---|---|
| Force | 4,000 N | 6,000 N meets or exceeds |
| Stroke | 500 mm | 1,000 mm meets or exceeds |
| Speed | 11 mm/s | 120 mm/s meets or exceeds |
Ball-screw servo electric cylinder in seven frame sizes from 32 to 150, with inline or reverse-parallel motor mounting and optional force sensing, aimed at hydraulic and pneumatic replacement.
| Published maximum | WhisperTrak | SRB Linear Servo Actuator |
|---|---|---|
| Force | 4,000 N | 49,033 N meets or exceeds |
| Stroke | 500 mm | 1,000 mm meets or exceeds |
| Speed | 11 mm/s | 1,250 mm/s meets or exceeds |
Screw-driven rodless actuator with recirculating ball-bearing guidance integral to the extrusion, so it carries loads up to 35.6 kN (with carrier options) without external guides.
| Published maximum | WhisperTrak | B3S Screw-Drive Rodless |
|---|---|---|
| Force | 4,000 N | 12,010 N meets or exceeds |
| Stroke | 500 mm | 4,547 mm meets or exceeds |
| Speed | 11 mm/s | 1,524 mm/s meets or exceeds |
Figures are the highest published for each series and are not always measured the same way. A higher figure is not automatically a better choice: mounting, duty cycle, feedback, connectors and approvals matter too. An engineer will check the fit against your application before recommending anything.
Typical applications
What a compact actuator is
A compact actuator is a self-contained electric linear actuator, typically with a low-voltage brushed DC motor, a gear stage and an acme or ball screw driving a rod. Most include built-in limit switches and can be powered by simply connecting 12 or 24 V DC, reversing polarity to change direction. Options often include position feedback by potentiometer, Hall sensors or encoders, and onboard control electronics. They are designed for simple, cost-effective movement rather than high-precision servo control.
When engineers choose a compact actuator
Choose a compact actuator for intermittent adjustments such as opening, lifting, tilting and positioning in mobility, medical furniture, agricultural and light industrial equipment. Installation is simple and cost is low. The trade-offs are duty cycle, speed and precision: many units are rated for intermittent duty, typically around 25% on time, and brushed motors wear. For continuous cycling or tight positioning, a servo-driven rod actuator is more appropriate.
How to specify the Thomson WhisperTrak
Send these with your enquiry and an engineer can confirm the right WhisperTrak variant or an equivalent:
- Supply voltage (V DC) and current limit (A)
- Force push and pull (N)
- Stroke (mm) and retracted length
- Speed under load (mm/s)
- Duty cycle (% on time)
- Feedback: limit switches, potentiometer, Hall or encoder
- Sealing (IP code) and temperature range (°C)
Common mistakes to avoid
- Running a 25% duty actuator continuously and overheating the motor
- Ignoring the drop in speed under load and voltage
- Not allowing for side loads in pivot mountings
- Assuming acme units always hold position under vibration
Thomson WhisperTrak: frequently asked questions
Can you help replace Thomson WhisperTrak or source the original?
Send the full model code, quantity and required date. Our engineers can check original-part availability and assess suitable alternatives, including supply-network options where appropriate. We confirm compatibility and any changes needed before recommending a replacement.
What is the Thomson WhisperTrak?
Quiet acme-screw DC actuator designed to medical electrical safety standards for patient handling and mobility products, up to 4,000 N; Thomson still publishes its product page in the legacy section. Published series figures include temperature -25 °C, temperature 40 °C, force 4,000 N, stroke 500 mm. It is made by Regal Rexnord; Specify Motion can help source it or propose an equivalent.
Who makes the Thomson WhisperTrak?
The Thomson WhisperTrak is made by Thomson (Regal Rexnord) and is listed here for engineers comparing options. Specify Motion is not affiliated with Regal Rexnord; brand names are used only to identify the product.
What is the temperature of the Thomson WhisperTrak?
The published series minimum temperature is -25 °C. Individual models and sizes in the WhisperTrak range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.
Is the Thomson WhisperTrak still available?
Thomson lists the WhisperTrak as legacy. We can help with spares for installed machines, a migration, or an equivalent from our supply network that meets the same published figures.
What does duty cycle mean for an electric actuator?
Duty cycle is the proportion of time the actuator can run without overheating, usually given as a percentage and a time window. A 25% rating means, for example, about two and a half minutes of running in every ten. Exceed it and the motor overheats. For continuous motion choose a unit rated for higher duty.
Do 12 V actuators hold their position when power is removed?
Many acme-screw compact actuators resist back-driving because of the screw and gear friction, and some add a brake. Ball screw versions are efficient and can back-drive under load. Vibration can still cause creep, so check the static holding force on the datasheet for the orientation and loads in your application.
Further reading: How to select a linear actuator · How to size a linear actuator · Linear actuators
Other compact actuator series
Engineer support
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Tell us how you use the Thomson WhisperTrak: the load, speed, duty and environment. Our engineers will confirm whether it is still the right part, find it for you, or propose an alternative that fits better.
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Prefer to configure it? Use the spec builder.
How it works
From enquiry to delivery
Send a part number or describe the application. Our engineers take it from there: the right product, a clear quotation, and delivery and support arranged.
- 01Tell us what you needSend a part number, or configure the application, quantities and timing.
- 02An engineer reviews itWe check the specification and find the original part, a checked equivalent or a complete axis.
- 03Receive your quotationProducts, pricing, lead time and compatibility notes in one reply.
- 04Order and deliveryWhen you are happy, the order is placed and delivery and after-sales support are arranged.