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Freezer Temperature Monitor/Alarm
with Backup LN2 or C02 Coolant Injection.

Model CA5000 (for C02) & CA5000 N (for LN2): Product Information


CA5000 Series Freezer Monitor with Carbon Dioxide or LN2 Backup Injection.

MODEL CA-5000 C02


  • 48-hour battery back-up in case of main power failure.
  • Digital display of interior freezer temperature, alarm set-point and freezer operating temperature.
  • Relay for connecting to any auto dialing or remote alarm.
  • Door switch input for safe injection of cryogenic LN2 or C02 within freezers/coolers for emergency interior temperature maintenance.
  • Large capacity, maintenance-free battery.
  • Exceptional value for functionality.
Model CA 5000 N, Freezer Alarm Monitor with Liquid Nitrogen Backup Injection.
Rear View of Freezer Alarm with Backup LN2 Backup Injection - Model CA 5000 by Hampshire Controls.
Made in USA Emblem

Product Overview:

CA5000 Series Systems are the ultimate in freezer backup protection for cold storage applications. This system goes beyond the basics of environmental monitoring, alarm indication and battery backup by providing a fourth level of operational maintenance - backup cooling injection for extended cold storage operation.

As a result of a serious mechanical failure or a long-term power failure, both CA5000 versions will activate their backup cooling capability after a designated programmed period. Once initiated, they will then directly inject either C02 or LN2 coolant into the freezer or cooler cabinet.

This additional backup capability is critical for the storage of blood/plasma, vaccines, virus samples, biopharmaceuticals and many other temperature-sensitive materials that MUST be maintained continuously within a tight cold storage temperature range.

Both models are simple to program and include the ability to set alarm temperature conditions, alarm delay periods and backup injection initiation conditions. The systems can operate for up to 48-hours using a built-in backup battery, and they store ALL programmed operating parameters within a non-volatile memory.

System Setup and Operation:

The temperature sensor and an output tube are first placed inside the freezer/cooler. Second, a tank of either cryogenic nitrogen or CO2 is connected to the system. Now your CA-5000 is ready to protect your cold storage lab freezer.

In operation, should a compressor fail, a refrigerant leak happen, or a main power failure occur, the system will notify you that an alarm condition exists and will then begin injecting backup cryogen to maintain critical storage temperatures. This approach provides a maximum "margin-of-safety" for continued cold storage until emergency repairs and/or product removal and transfer can occur (such as after local storms, regional power outages and hurricanes).

Key Operational Features:

  • Internal battery with integrated charger keeps the unit operating for at least 48-hours after a main power failure.
  • "BAT" indicator warns of a disconnected or low back-up battery condition.
  • Liquid Carbon Dioxide (CA 5000) version: Minimum backup time is a minimum of 8-hours - assuming the use of a single full "K sized" C02 cylinder at a backup temperature setting of -60 °C, and no door openings.
  • Liquid Nitrogen (CA5000 N) version: Backup time is ~ 48-hours, assuming the use of single 180 liter N2 cylinder at a backup temperature of -70 °C.
  • User-programmable setup of freezer temperature alarm and backup injection temperature.
  •  Visible and audible indicators of system status.
  •  Multiple level programmable alarm - to minimize nuisance or false alarms.
  •  Door safety interlock switch prevents coolant injection if freezer door is opened. Also, the system alarms if door remains open.
  • Relay outputs for automatic dialers.

CA 5000 Series Documentation:

CA5000 (C02) - Pricing

CA5000 N (LN2) - Pricing

CA5000 (C02) - Specs

CA5000 N (LN2) - Specs

CA5000 (C02) - Manual

CA5000 N (LN2) - Manual

Warrany, Shipping and Return Info


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