A Simple Example

Once we have measured the dimensions of the meter (see Getting Started) we can start to draw the new label. For this example we will duplicate the label for a cheap panel meter (like this one). The label measures 76 mm wide, by 45 mm tall, and is 4 mm above the needle bearing. The needle bearing needs a clear area of 13 mm radius. There are screw holes of radius 0.75 mm, 67 mm apart, 7 mm above the needle bearing.

First, create a new Python script and import meter.py. It is a good idea to specify that this is a Unicode file, in case you want to use special symbols on the meter text. We also include "#!/usr/bin/env python" for portability between different operating systems.

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

import meter

Next, create a meter object. Ours will be called simplemeter:

# Create the meter object
simplemeter = meter.Meter(
    # Dimensions for scale label (mm)
    label_width = 76, label_height = 45, label_offset = 4,

    # Radius of meter movement cutout (mm)
    cutout_radius = 13,

    # Screwholes at 31mm centres, 7mm from origin, dia 1.5mm
    screw_centres = 67.0, screw_offset = 7.0, screw_radius = 0.75,

    # fsd
    fsd = 90,
)

Next, we will add a µA (micro Amps) scale.

(to do)

Finally, we will write the SVG for our label to a file.

f=open("simple.svg",'w')
f.write(simplemeter.write_svg())
f.close

We can open the svg file in an SVG viewer, and print it to any printer. Firefox has SVG viewing and printing capabilities.