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How to read the specifications
Every parameter on this site is labelled with its basis, because a specification without a basis is a marketing claim. There are three labels and they mean exactly what they say.
Catalogue
A value transcribed from the supplied published catalogue. Confirm the current product revision and contractual rating in the quotation before ordering.
Derived
A figure normalised rather than reprinted. The commonest case is travel: the supplied catalogue quotes eleven of the seventeen linear models as a half-range — ±7.5 mm — and the other six as a total — 25 mm. The part number always encodes the total. On this site every travel is published as a total, with the source wording shown beside it, so nobody specifies a stage with half the stroke they need.
Not confirmed
A parameter absent, ambiguous, or not reliably mapped to the stated configuration in the supplied catalogue. It stays empty or carries an explicit source warning. It is never filled with a zero, and a horizontal payload is never reused as a vertical one. These are the fields currently in that state across the catalogue:
| Parameter | Unit | Why it is not published yet |
|---|---|---|
| Bidirectional repeatability | µm | The catalogue publishes one ± figure without saying whether it is unidirectional or bidirectional. |
| Measurement standard | — | No ISO 230-2 or equivalent reference is given for how accuracy was taken. |
| Test temperature | °C | Not stated. Thermal drift dominates at this resolution. |
| Load condition during test | — | Not stated. Accuracy under load is what an integrator has to design to. |
| Vertical and moment load limit | N·m | Only one payload figure is published, presumed horizontal and centred. |
| Motor holding torque | N·m | Only the NEMA frame size is given, not the torque curve. |
Three numbers that are not the same number
Resolution is the smallest increment you can command, set by the screw lead and the drive. Repeatability is how closely the stage returns to a point it has already visited.Positioning accuracy is how close it gets to the point you asked for, over the whole travel. Several crossed-roller linear entries list ±0.3 µm repeatability and 5 µm positioning accuracy. The two values are not interchangeable; quoting the tighter one as if it were the looser one is a common specification error in this category.
If the number you need is not here
Ask engineering to confirm it for the current model and intended operating condition.