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Log-Log Graph Paper For Time Current Curves

Can anyone tell me if a standard exists for the length per decade of log-log graph paper used in time current curve (TCC) plots?

Since these were designed for tracing, the scales of every manufacturers paper had to be the same. I've measured various originals and copies, and the distance appears to be about 2.21 inches per decade. However there is bit of variation between 2.20 to 2.23, the distance for vertical decades of time in seconds also seem to be a bit shorter than the horizontal distance for current in amperes.

It would be nice to know is there is some old ANSI standard or something that spells out how this paper is to be made.

Reply to
JuanDiegoDeLasNalgas
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A couple of years ago I was looking around the consulting engineering office where I work and I couldn't find any proper time/current curve paper. Seems we've modernized and are now using computer programs for everything...after a fair bit of tedious work I leaned the program well enough to get the results I'd have gotten in 20 minutes with the time-current paper. Ahh, progress.

Bill

Reply to
Bill Shymanski

In the UK the practice was to use the manufacturers curves to make templates which were then used on pads of graph paper. The usual manufacturer for the graph paper was a company called Chartwell. Although I am now retired I still have some of their paper in my archives. The 3 decade by 2 decade paper was based on 3" per decade. In the old UK manufacturers pamphlets the scales vary, so thescaling was not standardised amongst the manufacturers in the UK.

John

Reply to
John Rye

Variation -0.01 to +0.02 inch make that much of a difference? Coordination is an art not exact science - take an average, shift the paper and fudge a little. Anyway I never notice paper differences when laying out over a light table but was well over 10 years ago and couldn't tell you where my log-log papers are.

Reply to
Frank

--------- To add to your comments, since when can one use log-log graph paper with 2+ inches per decade with an expected accuracy of 1% or less? The variations in the paper are smaller than the variations in "reading" the graph. Ambient temperature will throw more uncertainty into the results than paper variations. This seems to be in the same category as " my calculator can give the answer (obviously always correct as it magically adjusts incorrect button pushing)to 10 figure accuracy even if the input data is known to 2 significant figures" --

Don Kelly snipped-for-privacy@shawcross.ca remove the X to answer

Reply to
Don Kelly

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