Hi Gary,
-
I do use a Fluke brand multi meter with the set up I described, I
should have mentioned that. The circuit layout does work
pretty well for me.
-
I have noticed that even the small Fluke Meter internal
resistance can and does change the loop current, more
than one might imagine.
-
I don't like using Multi or Ohm Meters direct onto unprotected
meter movements. The classic Simpson 260 meter will
damage a 200 uA movement on the higher resistance
positions.
-
cheers
skipp
-
--------- Forwarded message ----------
From: Gary Schafer <garyschafer@attbi.com>
That won't work exactly right. If the pot in parallel with the meter
matches
the meter resistance then the sum of the meter and parallel resistor is
1/2
of what the meter was alone. That will increase the series circuit
current
from what it was with just the meter so there will be more circuit
current
than exactly 1/2 the original current in the meter and the resistor. If
you
set the pot for 1/2 scale meter reading the pot and parallel resistor
will
each have a different current because the total series circuit resistance
has
changed and the circuit current is different.
It would work if you had a second meter to monitor the series circuit
current
and readjusted the series pot to maintain the same circuit current.
73
Gary K4FMX
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