Complete Application Data for EN 000.8 Position Indicators
Operating Principle
The position indicator is a self contained unit which is firmly mounted with a set screw to the central housing of the handwheel.
The spindle of the larger hand is also connected to the position indicator housing and the handwheel shaft. The larger
hand then monitors the number of revolutions of the main shaft at a ratio of 1:1. On the same spindle the weighted pendulum
(gravity controlled) is mounted in such a way that the rotating spindle does not impede the free suspended and static position
of the pendulum.
In other words, the independent pendulum remains static and the large hand counts the number of revolutions the handwheel
performs. Meanwhile, the reducing gear which is also mounted on the static pendulum is driven by the rotating idler cog
wheel and transfers this movement to the small hand which in turn will collate and display the number of completed revolutions.
The data collected by the two hands are: The small hand shows the number of completed revolutions and the large hand will
show the fraction of the incomplete revolution.
 Application
Position indicators with pendulum systems have the
advantage that the measuring system is completely
integrated in the operating element. They do not require
any modification for installation.
These position indicators can only be installed
in a horizontal position. However, due to the high precision of this measuring
gear, which is fitted with ball bearings and has an extremely low-lying gravity point, permits its use
in such cases with a spindle inclination of up to 60º.
Choosing the Reducing Gear Ratio
While the longer red hand reflects the rotational movement of the spindle at a ratio 1:1, the shorter black hand shows the fraction
of that movement as dictated by the reducing gear ratio.
The choice of the reducing gear ratio is dictated by the maximum number of rotations over the adjustment range. Therefore it is
recommended to apply a standard reducing gear ratio which is equal to or slightly larger than the maximum number of revolutions.
Example:
Adjusting range of the spindle: 11 turns
Chosen reduction: 12:1
By choosing this ratio, almost the entire scale range for position indication is available.
Scales
 The standard scales have a graduation range which complies with the reducing ratio.
The numbering sequence is also equal to the reducing ratio depending on the application, either increasing clockwise or increasing counter-clockwise.
If necessary a split table could be helpful in allocating scale numbers which suit particular applications.
Special scales available upon request.
Complete Diagram of Position Indicator EN 000.8 Installed in Handwheel
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