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Models 375-31H Area Monitor with Neutron Detector
Section 3
Ludlum Measurements, Inc.
Page 3-3
January 2021
Relays:
A 9-pin connector with male pins provides connection to three
fail-safe form C relays, activated by the LOW ALARM (alert) High
ALARM, and instrument FAIL. These contacts are potential-free (non-
powered), but can handle 125 Vac at 0.3 A or 30 Vdc at 1 A.
RS-232 Output
: a 2-second dump for computer data logging
Remote (optional)
: Ludlum Model 271 or 272 remote units
Audio:
Intensity can vary from approximately 68 dB to 100 dB through
operation of the external rotary baffle and the internal voltage
connection. Frequency is approximately 3 kHz.
Power
: 9 Vdc wall-mount adapter, handles any mains voltage in the
world, supplied with four sets of prongs for almost any style wall
receptacle
Battery Life
: typically 48 hours in non-alarm condition; 12 hours in alarm
condition
Battery Charger
: battery is continuously trickle charged when the
instrument is connected to line power and turned on
Warning!:
Only certified technician or calibration personnel should
replace battery.
Environmental Rating:
NEMA (National Electrical Manufacturers
Association) rating of 1; IP (Ingress Protection) rating of 40. (Protective
enclosures are available for harsher environments.)
Construction
: aluminum housing with ivory powder-coat finish
Size
: 18.7 x 24.6 x 6.4 cm (7.4 x 9.7 x 2.5 in.) (H x W x D)
Weight
: 2.1 kg (4.7 lb)