LUDLUM 12-4 User Manual

Model 12-4 Technical Manual Section 3
Ludlum Measurements, Inc. Page 3-1 May 2016
Specifications
Operating Voltage: approximately 1200 Vdc
Detector: 2 Atm
3
He tube – LND 25185 or equivalent – proportional
detector, surrounded by a 22.9 cm (9 in.) diameter polyethylene sphere
Detector Input Sensitivity: -2 mV
Sensitivity: typically 10,000 cpm per µSv/h (100 cpm/mrem/hr)
(
241
AmBe fast neutrons)
Detection Range: thermal to approximately 12 MeV, provides an
approximate inverse RPG curve (see below)
Meter: 6.4 cm (2.5 in.) arc, pivot-and-jewel suspension.
Meter Face: 0-10 mrem/hr, 0-2.5 kV, BAT TEST (others available)
Instrument Range
: typically 0-100 mSv/h (0-10,000 mrem/hr),
depending on the meter face utilized
Gamma Rejection: typically 10 cpm or less through 0.1 Sv/h (10 R/hr)
(
137
Cs)
Input Impedance: 0.1 megohm
Sectio
n
3

LUDLUM 12-4 Specifications

General

Brand	LUDLUM
Model	12-4
Category	Measuring Instruments
Language	English