Ludlum Model 2241-2
● Digital Radiation Ratemeter with Built-In Scaler
● Auto-Ranging and Adjustable Alarms
● Wide Range High Voltage
● Panel Mounted Locking Switch for Selecting 2 Detector Setups
● Supports GM, Proportional and Scintillation Detectors
● Overrange and Overload Protection
The Ludlum Model 2241-2 is a general purpose, digital radiation ratemeter with a built-in scaler that provides timed counts over a user specified period. This system will store detector setup information for up to two radiation detectors so personnel can easily change detectors in the field. The LCD presents readings in a four-digit moving decimal format together with one of a wide range of available units of measure and is accompanied by several operational and alert icons. The LCD backlight can be activated and remains lit for a user-adjustable interval. This instrument features adjustable alert and alarm setpoints for both the Ratemeter and Scaler modes. Front-panel controls include a rotary switch for selecting between Off, Ratemeter Mode, and Scaler Mode, switches for audio on/off and fast/variable response time, and push buttons for activating the LCD backlight for either resetting the counts or acknowledging any alarms. A locking toggle switch facilitates swapping detectors while preventing accidental switching.
PART NUMBER: 48-2731
general purpose radiation survey, gross counting
Readings are within 10% of true value with a detector connected.
auto ranging from 0.0 μR/hr–9999 R/hr; 0 cpm–999 kcpm
POWER: 2 each "D"
typically 200 hours with alkaline batteries (low battery warning on LCD)
The following parameters are adjusted for each detector by a removable switchboard. Once initial setup and calibration have been completed, the switchboard can be removed without affecting normal operation of the instrument.
BACKLIGHT “ON” TIME: 5, 15, 30, 60, 90, 120, 180, or 240 s for backlight to stay “ON” when activated
SET MINIMUM DISPLAY: allows lower limit of auto-ranging display to be fixed, for example, display can be set to not show values less than 1 mR/hr
RS-232 DATA DUMP MODE: enables or disables binary dump mode to RS-232 port, when enabled binary data will be dumped every 2 seconds
RS-232 DETECTOR SETUP MODE: allows for detector parameters to be input by RS-232 port
BAUD RATE: 150, 300, 600, 1200, 2400, 4800, 9600, or 19200 bps
DEAD TIME: adjustable from 0–9999 microseconds
CALIBRATION CONSTANT: adjustable from 0.001–280 X 109 counts/display unit
AUDIO DIVIDE: 1, 10, 100, or 1000 events per click
VARIABLE: Dependent on number of counts present. Typical times are FAST 4 to 25 s, SLOW 4 to 60 s (All times stated from 10% to 90% of final reading).
FIXED: The parameter is adjustable from 10 to 25 resulting in a FAST response from approximately 2 to 50 s. The SLOW response is approximately 10 to 250 s. For MDA-type measurements, the fixed response mode is recommended.
RATEMETER ALERT/ALARM: set at any value within the effective range of each detector
SCALER ALARM: adjustable from 1–999999 counts
SCALER COUNT TIME: adjustable from 1–9999 seconds
TEMPERATURE RANGE: -4 to 122 °F (-20 to 50 °C)
DETECTOR SETUPS: 2
DETECTOR SWITCH: two-way locking toggle switch
DISCRIMINATOR ADJUSTMENTS: 2
CE CERTIFIED: yes