The Ludlum Model 329-32 Laundry Contamination Monitor is intended for automatic monitoring of both alpha and beta-gamma contamination on clothing or other light articles presumed to be free of radioactivity, or within release or reuse limits. A motor-driven steel-mesh conveyor belt carries articles between two gas proportional detector arrays.
An audible alarm will sound when contamination exceeds the given alarm setpoint. A LED array spanning the belt shows the approximate position of the alarm on the conveyor, and provides the operator with the status of the machine. A dual LCD shows the counts and the current operating conditions, such as conveyor speed and gas flow.
A security-code protected 20-key keypad also allows the changing of alarm set points, operating parameters, and other system information. The entire system is mobile, with lockable casters to prevent unwanted movement of the monitor.
Each lower and upper detector array has 16 individual gas proportional detectors, providing 32 alpha channels and 32 beta-gamma channels for a total of 64 counting channels. A spare detector array (supplied with each system) allows for easy replacement, reducing down time. The detector arrays are staggered providing an even response across the conveyor. The usable detection width is 86.4 cm (34 in.) with an overall belt width of 91.4 cm (36 in.).
- Highly Automated System
- Simultaneous Monitoring of Upper and Lower Surfaces
- Lockable Caster Wheels
- 32 Alpha and 32 Beta-Gamma Channels
- Audible Alarm is Accompanied by Visual Indicator LEDs for Indicating Approximate Location of Contamination
- Real-Time Performance Status LEDs
- Pass-Through Tunnel Adjusts Up to 17.8 cm (7 in.) Height
| Application | Clothing and light article scanning | |
|---|---|---|
| System Control Panel | Two 40-character wide by 8-line LCD displays with back lights and 20-key control pad (provides count readings for each channel as well as system parameter information and control) | |
| Detector Arrays | Two arrays (one on top, one on bottom), each of sixteen 100 cm2 (15.5 in2) gas proportional detectors in two staggered rows of eight, providing a 86.4 cm (34 in.) wide continuous detection area | |
| Spare Array | A spare array is stored under unit and connected to gas for quick replacement if necessary. | |
| Recommended Counting Gas | P-10 (10% methane, 90% argon) | |
| Detector Window | 0.4 mg/cm2 aluminized polyester | |
| Array Area (each) | Active | ~ 2000 cm2 (310 in2) |
| Open | ~ 1600 cm2 (248 in2) | |
| Efficiency (4π) | 90Sr/90Y | ~ 22% |
| 230Th | 15% | |
| High Voltage | Adjustable from 200 to 2500 V | |
| Threshold | Alpha | 125 mV |
| Beta-Gamma | 2.5 mV | |
| Beta-Gamma Window | 50 mV | |
| Background Update | Can be done manually or automatically when no articles are on conveyor belt | |
| Count Time | Adjustable from 1 to 12 seconds | |
| Article Size | Maximum 17.8 x 86.4 cm (7 x 34 in.) (W x H). Upper conveyor adjustable from 0 to 17.8 cm (0 to 7 in.) above lower conveyor. | |
| Automatic Re-Scan | Feature allowing for automatic reverse and re-scan of articles when alarm is indicated | |
| Count Rate Alert | Adjustable from 0 to 9999 cps (indicated by yellow lamp and LEDs on operator panels) | |
| Count Rate Alarm | Adjustable from 0 to 9999 cps (indicated by red lamp and LEDs on operator panels) | |
| Audio | 2 unimorph-type speakers that are used to indicate the alarm conditions (greater than 68 dB at 0.61 m [2 ft]) | |
| Acknowledge | Pushbutton to silence audio | |
| Serial Port | Allows for output to printer | |
| Conveyor Belts | Two (one upper, one lower) 91.4 cm (36 in.) wide stainless steel woven mesh belts (80% open) | |
| Conveyor Speed | Adjustable from 0.25 to 14 cm/s (0.1 to 5.5 in/s) | |
| Run | Green pushbuttons on operator control panels and side of unit to start conveyor | |
| Stop | Red pushbuttons on operator control panels and side of unit to stop conveyor | |
| Reverse | Yellow pushbutton on side of unit to reverse conveyor | |
| Emergency Stop | Conveyor is encircled by pressure-sensitive bump bar to automatically stop conveyor when touched | |
| Power | 95 to 135 VAC (220 VAC available) | |
| Construction | Steel frame and aluminum electronics housing | |
| Temperature Range | -15 to 50 °C (5 to 122 °F) | |
| Size (H x W x L) | 150 x 116 x 282 cm (59 x 45.8 x 111 in.) | |
| Weight | 250 kg (550 lb) | |
| Shipping Size (H x W x L) | 152 x 122 x 301 cm (60 x 48 x 119 in.) | |
| Shipping Weight | 568 kg (1250 lb) | |
