Ludlum Measurements 239605, Manual

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Model 3-IS & 3-IS-1 Technical Manual
Section 4
Ludlum Measurements, Inc. Page 4-2 October 2010
the higher the audio frequency. The audio should be turned
OFF
when
not required to reduce battery drain.
Note:
A low battery condition results in a steady audio tone regardless
of the position of the
AUD ON
/
OFF
switch.
F-S Toggle Switch
: Provides meter response. Selecting the fast, ˝
F
˝
position of the toggle switch provides 90% of full scale meter deflection
in four seconds. In the slow, ˝
S
˝ position, 90% of full scale meter
deflection takes 22 seconds. In
˝
F
˝
position there is fast response and
large meter deviation. The ˝
S
˝ position should be used for slow response
and damped, meter deviation.
Note:
The slow response position is normally used when the instrument
is displaying low numbers that require a more stable meter
movement. The fast response is used at high rate levels.