Ludlum Measurements 25024424, Manual

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A
P
P
E
N
D
I
X
A
M
ODEL
30 V
ARIATIONS
A.1 Model 30-4
A Model 30-4 is a Model 30 Digital Display Unit paired with a neutron detector. The range is
0-100 mSv/h (0-10,000 mrem/hr). The display unit detaches for greater versatility.
A.1.1 Detector
The
3
He proportional detector is 1.6 x 2.5 cm (0.6 x 1.0 in.) (Dia
x L) and is surrounded by a 22.9 cm (9.0 in.) diameter cadmium-
loaded polyethylene sphere. It typically has a sensitivity of 10 cpm
per
µ
Sv/h (100 cpm per mrem/h) with a linearity reading within
10% of actual value.
The energy response provides appropriate inverse RPG curve for
neutrons from thermal through 7 MeV and provides a response up
to 12 MeV.
A.1.2 Specfications
Gamma Rejection: < 10 cpm through 0.1 Sv/hr (10 R/hr) (
137
Cs
gamma)
Operating Voltage: approximately 1200 Vdc
Threshold: -2 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)
Environmental Range:
NEMA (National Electrical Manufacturers
Association) rating of 3x or IP (Ingress Protection) rating of 52, with
audio hole seal option
Size: Display unit 8.5 x 8.0 x 4.8 cm (3.4 x 3.1 x 1.9 in.) (H x W x L); Detector 22.9 cm (9in.)
REM ball with
3
He detector (1.6 x 2.5 cm)
69