Where do you find dimensions for drafting symbols to their standard?

Question

Where do I find the official dimensions to draft electrical symbols according to their standard?

So far, I've referred to ANSI/ISA-5.1-2009 to draw instrumentation symbols. In it, there is a section that breaks-down the drafting components for each symbol. From these building blocks, you can draw all the instrumentation symbols listed in the standard.

However, I'm trying to draw a resistor to IEEE standard, and ANSI-Y32.2-1975/IEEE-315-1975 don't have the same section with the broken-down drafting components. None of my searches on google along the lines of 'resistor dimensions drafting' are fruitful for finding these dimensions.

So, where exactly can I find the dimensions to draw the symbols found in IEEE-315. I would also like to know where I can find the dimensions to draw their IEC equivalents (IEC 60617).

Answer 1

From IEC 60619 database:

Each graphical symbol is identified by a reference number and contains a title (in English and French), a graphical representation in GIF and some additional data as applicable. Some of graphical symbols are available as vectorized EPS format. Various search and navigation facilities allow for easy retrieval of graphical symbols.

In addition, the standard includes the drawings over a dot matrix of 2.5mm.

About other standards, from "Resistor Symbols" here :

Several standards exist, which describe how the different components should be displayed. In the past, a lot of countries and even individual industries used their own standards, which can be confusing. Nowadays, the IEC 60617 standard is the international standard for these electronic symbols. However, local standards are still used from time to time. In general, the ANSI standard is still common in the United States. Some examples of standards which describe resistor symbols:

IEC 60617 (International)
ANSI Y32 / IEEE 315 (US) - old
DIN 40900 (Germany) - old
AS 1102 (Australia) - old

Answer 2

In IEEE Std 315, take a look at sections A4.4 and A4.5 and the footnote to section A4.5 as well. The standard does not dictate a specific size, but says that the relative size of the symbols should be maintained as it is in the standard. All of the symbols are presented so that their connection points will fall on the same grid.

I know this is not great, but I have taken the graphic symbols and imported them into Inkscape. I turned on a grid with my preferred wire spacing and changed the size of the images until their connection points fell on that grid. In many cases I redrew the images using vectors and arcs to replace the bit-mapped images I got from the standard.

Answer 3

Here are some drawing templates that show two examples the size used for hand drawing. Drawing were made on various sizes of paper and full-scale prints were made from the drawings. Photographically reduced-size copies where also made to perhaps 25% of the original size.