Ludlum Measurements 239605, Manual

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Model 3-IS & 3-IS-1 Technical Manual
Section 4
Ludlum Measurements, Inc. Page 4-1 October 2010
Identification of Controls and
Functions
See the Model 3-IS FRONT PANEL drawing at the
beginning of this manual to reference the following
controls:
Meter
: 2.5" (6.4cm) arc, 1 mA analog type with pivot-and-jewel suspension.
Typical meter dials are 0-2 mR/hr, 0-20 µSv/h, 0-5k cpm or combination of
exposure rates (0-2 mR/hr or 0-20 µSv/h) and cpm and
BAT TEST
.
Connector
: (Model 3-IS only) Series “C”, used to connect the detector to the
instrument.
Range Selector Switch
: A six-position switch marked
OFF
,
BAT
, ×100, ×10,
×1, and × 0.1. Turning the range selector switch from
OFF
to
BAT
provides
the operator with a battery check of the instrument. A
BAT
check scale on the
meter provides a visual means of checking the battery-charge status. Moving
the range selector switch to one of the range multiplier positions (×100, ×10,
×1, and × 0.1) provides the operator with an overall range of 0 to 500,000
cpm. Multiply the scale reading by the multiplier to determine the actual scale
reading.
Calibration Controls
: Recessed potentiometers which are used to calibrate
the individual range selections and allow for high voltage adjustment from
400 to 1100 volts. A protective cover is provided to prevent tampering.
Battery Compartment
: Sealed compartment to house two ˝
D
˝ cell batteries.
RESET Button
: When depressed, this switch provides a rapid means to drive
the meter to zero.
AUD ON-OFF Switch
: In the
ON
position, operates the unimorph speaker,
located on the left side of the instrument. The frequency of the clicks is
relative to the rate of the incoming pulses. The higher the rate,
Section
4