A mechanical testing machine rated Level 0.5 is telling you something specific: that its indicated force stays inside a tight error band across a wide working range, and that its rate control holds the same discipline. It is not telling you that the readout is fine to the last digit. Resolution and accuracy are two different promises, and confusing them is the most common mistake we see when a machine arrives for acceptance.Get more news about mechanical testing machine,you can vist our website!

This guide follows the order a run test actually happens, not the order a specification sheet is printed. We will work through five steps in sequence: what a class really defines, what separates Level 0.5 from Level 1, why resolution is not accuracy, why the machine class is not the sensor class, and finally what to verify on your floor before you sign. Each step builds on the one before it, so read them in order.

The short version, if you only read this far

A class is a package: indication error, usable force range and rate control are judged together.
Level 0.5 starts usable measurement at 0.2% of full scale; Level 1 starts at 0.4%.
A fine resolution number describes the step size, not how close that step is to the truth.
The frame, the alignment and the control loop are all part of the measurement, so the machine can rate lower than its sensor.
Step 1: What a Class Actually Defines on a Mechanical Testing Machine
A class is not one number. It is a package of three behaviours measured together, and a machine only earns the class when all three meet it. Reading a single figure off a datasheet and calling the machine accurate is where most acceptance disputes begin.

Indication error — how far the force the machine displays can sit from the true force applied, expressed as a percentage of the indicated value.
Usable force range — the span of the scale in which the class claim actually holds. Below that floor, the machine is a working instrument but not a certified one.
Rate control error — how precisely the machine holds the speed you asked for, in force rate or in strain rate, because a test is a rate as much as it is a load.
Put plainly, the class answers three questions at once: is the force reading right, over what part of the scale, and does the machine run at the speed it says. A machine can pass on the first and fail on the third, which is why the rate figure appears in the same table as the accuracy figure. Our electronic universal testing machine carries both figures on one line for exactly this reason.

Once you accept that a class is a package, the next question is concrete: what does that package look like when you compare Level 0.5 against Level 1 side by side?

Step 2: What Separates Level 0.5 From Level 1
Level 0.5 beats Level 1 in three ways that matter to a real test: a wider usable range, a tighter force error, and a slower usable control rate. Here is the comparison as it appears on our own machines, where Model B is Level 0.5 and Model A is Level 1.

Specification Model B (Level 0.5) Model A (Level 1)
Force range 0.2% to 100% FS 0.4% to 100% FS
Indication error ±0.1% / ±0.25% of indicated force ±0.5%
Force rate control 0.005 to 5% FS/s 0.01 to 5% FS/s
Strain rate control range 0.02 to 5% FS/s 0.05 to 5% FS/s
Force resolution 1/500,000 of full scale 1/200,000 of full scale
Displacement resolution 0.015 µm 0.001 mm
Displacement indication error ±0.2% ±0.5%
Look at the force range first, because that is where the money of a specification sits. On a 600 kN machine, Level 0.5 starts being certified at 0.2% of full scale, which is 1.2 kN, while Level 1 only starts at 0.4%, or 2.4 kN. If your most interesting test loads live in the low end of the scale — small components, thin films, delicate joints — that floor decides whether you can claim the test at all. The tighter error band and the slower usable rate control follow the same logic: they let you run a slower, gentler test and still have it count.

The machine also carries the frame behind those numbers: three force ceilings of 100 kN, 300 kN and 600 kN, a Panasonic servo motor drive, and conformity to GB, ISO, JIS, ASTM and DIN. Which of those ceilings fits your work is a separate question, and we cover it on the mechanical testing machine range.

With the class differences clear, the next question is the one that misleads more buyers than any other: what do all those resolution digits actually promise?

Step 3: Why Resolution Is Not Accuracy
Resolution is the smallest step the machine can display. Accuracy is how close that step is to the truth. A scale that reads to a gram can still be a gram wrong, and a load cell that resolves to a thousandth of the range can still be out of calibration. The two numbers are printed next to each other, which is exactly why people merge them.

Force resolution of 1/500,000 of full scale means the display can step in very fine increments. It does not mean each step is right. That is the job of the indication error figure from Step 2.
Constant resolution across the full range, with no range switching, means you never stop mid test to change a setting. You keep one continuous trace instead of stitching ranges together.
Displacement resolution of 0.015 µm describes how finely the crosshead position is reported. It says nothing about whether the frame is straight or the fixture is aligned.
The LINE 2500 r/p optical encoder is what feeds that displacement figure. A good encoder improves the step size; it does not correct a bent specimen.
The practical test is simple. Ask yourself what you would do with the extra digits. If your specification only cares whether a part held above a force threshold, a fine resolution does not help you, and a tight indication error does. If you are resolving a slope on a soft material, both matter. Resolution is a convenience feature; accuracy is what a certificate is built on.