Why are 'short scale' panel meters synonymous with industrial applications?

[e100]

By short scale I mean the type where it looks like a third of the meter has been chopped from the right hand side so the coil and magnet are in the bottom right hand corner and the needle can only move through 90 degrees.


Is this supposed to give better at a glance readability? If so, wouldn't things like car dashboard instruments adopt the same look?

[Gyro]

I'm not sure they are actually that short. If you rotate the picture by 45' they look about the same span as a normal meter movement. Linearity starts to suffer once you get much past 90'. I've seen ~270' meters used in similar control room applications, not sure how how they work though.

The meters shown do have visual impact though, maybe easier to spot deviations in an array.

[David Hess]

I think it is just a matter of making the best use of available space.

[e100]

I'm not sure they are actually that short. If you rotate the picture by 45' they look about the same span as a normal meter movement. Linearity starts to suffer once you get much past 90'. I've seen ~270' meters used in similar control room applications, not sure how how they work though.

I had assumed that 'short scale' was the official name for this type of meter layout with the axis in the right hand corner, but now I don't know if it has an official name at all.

The meters shown do have visual impact though, maybe easier to spot deviations in an array.

Is it perhaps the east/west everything is dead, north/south everything is on fire user interface paradigm?

[duak]

Many race cars have their tachs and other gauges set up so that their nominal or maximum readings occur with the meter needle vertical to make it easier to see if one is out of range.  These gauges are usually round so they can be easily rotated,  Rotating a square meter would look goofy if not downright confusing.

The cynic in me says it's a fashion statement that says 'Industrial' rather than simply 'Professional'.  (Sometimes I think we need a new word that means what professional used to mean, especially in ads.)

Industrial meters often use moving iron movements rather than moving coil (D'arsonval) movements.  I believe this allows for 270 (actually 240) degree sweeps.  I also remember seeing a thermal movement where a heated wire indirectly pulled on a gear train to drive the needle.  This could measure the actual RMS current rather than the average.

 

[David Hess]

Moving iron movements are RMS responding.

[Gyro]

240' apparently possible in moving coil meters too... https://www.hobut.co.uk/analogue-panel-meters-3/240-degree-din-panel-meter

It looks as if they use a 'half coil', the turns must pass through the center of the magnet...