Do you have a specific task? We will get back to you with a recommendation.
If no catalogue transducer fits your design, we build one: custom force transducers, load cells and weighing cells to your drawing, from the initial concept through FEM design, manufacturing and strain gauge application to the calibrated series. Design, CNC machining, strain gauge application and calibration laboratory are all under one roof.
The initial concept is free of charge, and the quantity can be one.
Free initial concept
proposal usually within 3 working days
from quantity 1
single piece, prototype or series
up to +250 °C
temperature compensation in special design
up to SIL 3 / PL e
redundant, with two independent strain gauge bridges
Check first: will a standard design do?
A standard design is faster and cheaper than any custom build. Several hundred products in many rated loads are available online with datasheet, price and delivery time. So it is worth looking here first:
Tension and compression force transducers
threads at both ends, for tension, compression and alternating load, see tension & compression
Button load cells
pure compression, flat and compact, see button load cells
Force measuring rings
with a through-hole, for example for bolt preload, see force rings
Miniature force transducers
from 1 N rated force, when the space is only a few millimetres, see miniature
S-type force transducers
for testing machines, cranes and suspended loads, see S-type
Flange and spoke cells
high forces at a low height, see flange & spoke
Load pins
replace an existing pin in the force flow, see load pins
Multi-axis force sensors
several force directions at once, see multi-axis
The complete overview is under load cells & force transducers.
When a custom design is needed
Standard designs reach their limits as soon as one of these conditions applies:
Installation space
thread, flange, bolt pattern or height are fixed
Rated force
lies between two series or outside the standard range
Temperature
above +80 °C at the measuring point; compensation up to +250 °C is possible, see high temperature
Safety
redundant design or rating up to SIL 3 / PL e, see functional safety
Existing component
is to become the measuring element itself, without rebuilding the machine
Signal and connection
4…20 mA, 0…10 V, IO-Link, CANopen (optionally CANopen Safety), PROFINET (optionally PROFIsafe), connector or cable as specified
Material and protection
stainless steel, hermetically sealed, IP68 or IP69K, ATEX and explosion protection
Depending on usage, such transducers are called special force transducers, custom designs, custom measuring transducers or simply "transducers to drawing". They all mean the same thing.
From our production
A selection of custom transducers we have designed, manufactured, gauged and calibrated:
Examples from the last two years
No customer names, but real figures: tasks we have recently solved.
Further custom solutions from this period:
Nuclear power plant
six ring force transducers for 150 kN, each individually calibrated according to ISO/IEC 17025
Mobile machinery
load cells with CANopen Safety (CiA 304) for overload protection to PL d on a bridge inspection vehicle
Clamping technology
force transducer for 38 kN in a zero-point clamping system, stainless steel, IP65
Process technology
S-type load cells from 100 to 300 kg, temperature-compensated up to +150 °C, for operation in a vacuum of about 1 mbar
What else is possible
From enquiries and designs we are currently working on. Tasks like these are everyday work for us:
Hydrogen
ring force transducers from 6 to 300 kN for electrolysis stacks
High forces
tension and compression transducers for 10 MN, for presses and testing machines
Up to +275 °C
strain gauge measuring package for axial force, preload and bending moment on a process valve, feasibility study completed
Tunnelling
redundant ring force transducer with two measuring bridges up to 500 kN for monitoring chain forces
Large series
load pins for 15 kN, around 20,000 pieces over three years
Tubular design
tubular force measuring cell for 500 kN, IP68, with connector
The process: from enquiry to series
Initial concept, free of charge
You send the drawing, force direction, rated force and installation situation. Within 3 working days you receive a proposal for turning it into a measuring element, with an estimate of accuracy, effort and price range.
FEM calculation
Before designing, we calculate the geometry: strain at the measuring point, limit load, overload safety.
Design and manufacturing
We machine the spring body in-house, see CNC machining.
Strain gauge application
foil strain gauges as a full bridge, cold or hot curing depending on the application, see strain gauge application.
Calibration and test report
in a replicated installation, on request according to ISO 17025 in our own laboratory, later also recalibration.
Single piece or series
Both. The design is the same either way; for reorders we store the configuration.
If the measuring task needs more than the transducer, we also build the test rig, see the report test rig construction: force measurement in two and three axes.
Technical data
| Feature | Standard for custom designs | on request |
|---|---|---|
| Design | fatigue-resistant, for tension and/or compression | – |
| Temperature compensation | -40 to +80 °C | up to +250 °C |
| Limit / breaking load | 150 % / 300 % of rated load | for example 300 % / 500 % |
| Zero point | no zero drift, no periodic recalibration | – |
| EMC immunity | 200 V/m | – |
| Protection class | IP68 / IP69K | hermetically sealed |
| Safety | – | redundant, up to SIL 3 / PL e |
| Signal | passive mV/V | integrated amplifier: 4…20 mA, 0…10 V, IO-Link, CANopen, PROFINET |
| Connection | cable | cable or connector to your specification |
| Calibration | in a replicated installation, with test report | according to ISO 17025 |
Integrated electronics instead of a separate amplifier
Depending on the space available, the amplifier sits directly in the transducer or compactly in the cable. The mV/V signal of the full bridge becomes an industrial signal straight away, with no separate device in the cabinet and no sensitive millivolt line.
In the housing
the amplifier sits in the transducer, output directly 4…20 mA, 0…10 V or IO-Link
In the cable
compactly integrated when there is no room for electronics in the spring body
Remote
the better choice at high temperatures at the measuring point, see measuring amplifiers
Application reports
More reports are under application reports.
Free initial concept
Send us a drawing or sketch, rated force, force direction and installation situation. Within 3 working days you receive a proposal with an estimate of accuracy, effort and price range. The initial concept costs you nothing.
What we need for a quotation
With this information you get a reliable quotation instead of a follow-up question:
- Rated force and direction: tension, compression or both
- Drawing or sketch with the connection dimensions
- Installation: where the force acts and how the transducer is supported
- Environment: temperature range, protection class, hazardous area
- Signal and connection: mV/V, analog or digital, cable or connector
- Safety requirement: whether SIL or PL is required
- Quantity and required date
A photo of the installation site is often enough for a first assessment. If something is missing, send what you have; we will clarify the rest together.
Frequently asked questions about custom designs
From what quantity is a custom design worthwhile?
Even for a quantity of one. The effort lies in design, manufacturing of the spring body and strain gauge application, not in the series. A single piece is therefore not a special case but the normal case in development and test rig construction. For series the unit price drops accordingly, and we store the configuration for identical reorders.
What does a custom force transducer cost?
That depends on design, rated force, signal output, protection class and required certification. An adapted standard geometry costs considerably less than a completely new design with redundancy and safety rating. So that you know where you stand before ordering, our initial concept is free: it gives you an estimate of effort, achievable accuracy and price range.
How long does a custom design take?
You usually receive the initial concept within 3 working days. Production time depends on design, quantity and certification; for custom load pins it is typically 8 weeks from drawing approval. We state the binding date in the quotation. If a deadline is tight, say so in your enquiry and we will check what can be brought forward.
Can you turn an existing component into a sensor?
Yes, and it is often the more elegant solution. Instead of installing a transducer in the force flow, we apply strain gauges directly to your component, for example a press frame, a shaft or a frame profile, and calibrate the measuring chain. The machine stays unchanged and no installation space is lost.
What accuracy can a custom design achieve?
That follows from geometry, load introduction and installation, not from the sensor alone. A spring body with well-defined load introduction reaches values in the range of standard transducers; an instrumented component with unknown load distribution stays below that. We state the achievable accuracy in the initial concept, so you can assess the measuring task beforehand.
What is the difference between force transducer, load cell and weighing cell?
Technically it is the same component: a spring body with strain gauges in a full bridge. The difference is the application and therefore the calibration. Calibrated in kilograms or tonnes it is called a load cell for weighing; calibrated in newtons or kilonewtons, a force transducer.
Do you supply the transducer calibrated?
Yes. Every custom design is calibrated and supplied with a test report, in a replicated installation. A transducer reacts differently depending on load introduction and support; a certificate from a generic test setup says little about your application. On request we calibrate according to ISO 17025 in our own laboratory, and later recalibrate as well.
Are higher temperatures, explosion protection or safety levels possible?
As standard our custom transducers are compensated from -40 to +80 °C, on request up to +250 °C. For hazardous areas we supply ATEX and IECEx versions, for safety-related applications redundant transducers up to SIL 3 and PL e. Protection classes up to IP68 and IP69K are possible with hermetically sealed designs.
Can the electronics be integrated into the transducer?
Depending on space, yes. The amplifier then sits in the sensor housing or in the cable, and you get 4…20 mA, 0…10 V, IO-Link, CANopen or PROFINET directly instead of an mV/V signal. If it is very hot at the installation point, the separate design with a remote amplifier is the better choice.
Send us a drawing or sketch, rated force, force direction and installation situation via the quotation form or directly to office@octogon.org. The initial concept costs you nothing.