rshayes:
Actually after i drew it i noticed that too, and was going to change it
but was getting a bit tired at that point. Later, i took a look at the
possible current distributions and they didnt look too much different
so i decided to leave it alone. It is true that they will be better with
the opposite ends connections, but it doesnt make an extremely
huge difference, that is, enough to cause one strip to overheat.
It doesnt affect calibration at all either...when connecting the sense
leads to the center strip...the heavy leads can be connected either
way.
While i was looking over the mechanical aspect of this design i
also realized that it is a bit much anyway. The eight separators
have to be cut from 1/8 inch stock and have a 1/4 inch clearance
hole drilled in each one. I realized there is a much simpler way,
which is the subject of this next drawing.
This shunt only requires two strips of brass and a little bending
and the holes should be easy to drill too. The current distribution
is nearly perfect (equal in both strips). Of course the 1/4-28 bolts
should be well tightened.
To calibrate, unsolder an amp lead and move it one way or the
other to get the reading to be more accurate at some known current.
The dimensions for this new shunt come about from the resistivity
of the brass that i had obtained from a hobby shop quite a while back.
If the brass isnt exactly the same, the dimensions might have to
change a little unless the calibration makes up for it ok.
