Model LD 215: Liquid Nitrogen Level Monitor with Alarm for Ultra Low Temperature Freezers/Dewars.
Model LD 215 Product Information.
- Application specific probe lengths for different container sizes and required liquid/vapor levels.
- Audible & visual alarms.
- SPDT alarm contact output.
- 100-ohm cryogenic RTD probe.
- 0.250-inch/6.35 mm optimum level change resolution.
- Low-level or overflow mode operation.
- User adjustable initial alarm delay and mute periods.
- Battery backup with (2) rechargeable AA batteries included.
- Shaft collar and wrench included for probe positioning.
The Model LD 215 enables monitoring of liquid nitrogen levels in ultra low temperature freezer and dewar storage systems where maintaining continuously accurate cold storage temperatures is critical. Such applications include medical laboratories, biological research labs, vaccine development labs and for in vitro fertilization (IVF) clinics.
The Model LD 215 tracks liquid nitrogen levels in cryogenic vessels using a special 100-ohm cryogenic RTD probe located within the ULT freezer unit. The system is able to sense rising temperature due to a liquid level drop caused by evaporation. When an alarm threshold is reached, an audible/visual alarm is triggered and corrective action can then be taken. The unit can also be used to detect overflow liquid nitrogen (LN2) levels.
Level indication resolution is approximately 1/4-inch (due to potential frost accumulation on the sensor probe and the ambient temperature within the container). However, once an ideal position is established, the probe will repeatably detect low or high LN2 levels.
An out-of-tolerance alarm condition is signaled by a flashing red LED and a pulsing beeper. If the probe is disconnected (open) the red LED and beeper will remain on steadily. Alarm conditions can also be muted for a user-selectable period of up to 60 minutes.
The unit is shipped with a plug-in power supply and a battery backup. Single pole alarm relay double throw (SPDT) contacts are brought out to tool-less spring-loaded connectors.
- Auto Dialers (Models AD 2000 and AD 2001): System dials a phone/pager to immediately provide alarm notification whenever a set alarm level is triggered.
- Remote Alarm Delay Module (Model ADM 215 with Audible & Visual Alarm Indication.