Model 3A

General Purpose Survey Meter with Alarm

Part Number: 48-1408

Features

• Low Price
• Rugged
• 4-Range Analog Ratemeter
• Alarms
• Supports GM & Scintillation Type Detectors

The Model 3A is identical to Ludlum's best selling, general purpose, Model 3 handheld analog ratemeter with the addition of an audible alarm. It is likewise known for its accuracy and long-lasting dependability. The cast aluminum instrument housing with its separate battery compartment and accompanying metal handle offer an industrial robustness and quality that promote long-lasting protection and instrument life.

The front-panel controls include a rotary switch for selecting the four-decade range, instrument shut-off, and battery test, an audio on/off switch, a fast/slow response switch, and a count reset button. The analog meter comes in a variety of measurement ranges and units to support the external radiation detector selected.

A one meter (39 in.) long straight type detector cable with "C" style connector is included in the price of the instrument.

• Specifications
• Meter Faces
• Options
• Documents

• Specifications
• Meter Faces
• Options
• Documents

Specifications

Application	Alpha, Beta, Gamma survey
Compatible Detectors	GM, Scintillation
Detection Range	Dependent on detector
Linearity	Reading within 10% of true value with detector connected
Meter Dial	0 - 2 mR/hr, or 0 - 500 cpm, BAT TEST (Meter Faces tab lists other available meter faces)
Meter	6.4 cm (2.5 in.) arc, 1 mA analog type
Controls	Rotary Selector Switch: Switches between: Instrument off; Battery check; Ranges: ×0.1, ×1, ×10, ×100 Response Switch: Toggles between FAST (4 s) or SLOW (22 s) from 10% to 90% of final reading Reset Pushbutton: Zeroes meter Audio Switch: Audio on/off, built-in unimorph speaker, greater than 60 dB at 0.6 m (2 ft) Calibration Controls: Accessible from front of instrument (protective cover provided)
Alarm	Indicated by red lamp on front panel and constant audio tone. The alarm circuit is triggered by meter deflection.
High Voltage	Adjustable from 400 to 1500 Vdc
Threshold	Fixed at -30 mV ± 10 mV
Temperature Range	-20 to 50 °C (-4 to 122 °F) May be certified for operation from -40 to 65 °C (-40 to 150 °F)
Power	Two each "D" cell batteries (housed in externally accessible sealed compartment)
Battery Life	Typically greater than 2000 hours with alkaline batteries (battery condition can be checked on meter)
Construction	Cast and drawn aluminum with beige powder coat
Connector	Series "C" (others available)
Size (H x W x L)	16.5 × 8.9 × 21.6 cm (6.5 × 3.5 × 8.5 in.), including handle
Weight	1.6 kg (3.5 lb), including batteries

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Meter Faces

This table lists the most commonly used meter faces. Others are available upon request.

 

Meter Face	Image (click to view larger}	Description	Detectors
202-043		0 - 50 cps BAT TEST	Model 44-2
202-1092		0 - 9 kcpm 0 - 0.1 µSv/h BAT TEST	Model 44-10

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Options

Option	Description	Part Number
Portable Scaler Option	Adds scaler counting capability. Includes digital readout, count time selector switch, and count control button.	4464-114
Overload Indicator Option	Adds Overload indicator with a light.	4464-130
Detector Clips	Stainless steel clip attaches to instrument handle or case facilitating one-handed carrying of instrument and detector.	Depends on detector.
Lighted Handle	Handle with LED to illuminate the instrument display.	4464-154
Shoulder Strap	Adjustable nylon shoulder strap.	4363-413
Headphone Jack	Adds headphone jack to instrument.	4464-464
Stereo/Mono Headphones	Adjustable stereo/mono headphones.	22-9313
Transport & Storage Case - Small	Rugged, dust- and waterproof transport and storage case.	2311062

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Documents

• Data Sheet
• Product Manual
• CE Certificate

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