LAUDA ECO REJ 1225 G Calibration Constant-Temperature Bath

Overview

The LAUDA ECO REJ 1225 G Calibration Constant-Temperature Bath is a precision-engineered thermal reference system designed explicitly for metrological traceability in temperature sensor calibration laboratories. Operating on the principle of forced-convection liquid bath thermoregulation, it delivers exceptional thermal homogeneity and temporal stability across its full operating range of −25 °C to +200 °C. Its dual-chamber architecture—comprising an outer reservoir and inner calibrated working zone—ensures constant fluid level during operation, while the vertically adjustable overflow weir maintains consistent immersion depth for thermometers under test. This design directly supports compliance with ISO/IEC 17025 requirements for calibration uncertainty control and aligns with ASTM E77, ISO 17034, and EURAMET cg-18 guidelines for liquid-bath thermometer calibration. The unit employs a fully electronic PID controller integrated with a high-efficiency microprocessor-based system, enabling sub-millikelvin-level stability (±0.02 °C) and rapid thermal equilibration—critical for primary and secondary calibration workflows involving glass-in-glass thermometers, RTDs, thermistors, and digital probes.

Key Features

• Thermal stability of ±0.02 °C at setpoint, verified per DIN EN ISO 9001-accredited procedures
• Vario centrifugal pump with six discrete flow-rate settings, allowing independent optimization of internal circulation (for bath uniformity) and external recirculation (for auxiliary equipment integration)
• Color TFT graphical display showing real-time temperature curve, setpoint, actual value, and status indicators—enabling visual verification of thermal settling behavior
• Full menu-driven interface with soft-key navigation and dedicated Tmax overtemperature protection key; configurable safety thresholds accessible via protected service mode
• Stainless steel bath vessel (Ø150 × H200 mm) with integrated drain valve and removable lid; compatible with water, silicone oil, and low-volatility heat-transfer fluids
• Class III electrical safety certification per IEC 61010-1, permitting safe operation with flammable media such as ethanol or isopropanol
• Compliance with EU F-Gas Regulation (EU) No 517/2014 through use of HFC refrigerants with verified GWP documentation
• Expandable communication architecture: USB port standard; optional field-installable modules for analog 0–10 V / 4–20 mA output, relay contacts, RS232/485, Profibus DP, or Ethernet-to-USB bridging
• Programmable sequence controller supporting up to 150 time–temperature segments across five independent programs—ideal for automated multi-point calibration protocols

Sample Compatibility & Compliance

The REJ 1225 G accommodates standard immersion lengths from 150 mm to 300 mm, with vertical adjustment of the overflow edge ensuring repeatable meniscus positioning relative to the calibration reference plane. It supports both direct-read and fixed-point thermometer configurations, including mercury-in-glass, alcohol-filled, Pt100 probe assemblies, and thermocouple sensors mounted on LAUDA-certified calibration stands (optional). All materials in contact with bath fluid meet USP Class VI biocompatibility standards where applicable. The system conforms to GLP documentation requirements through audit-trail-capable firmware (when paired with LAUDA’s LabSoft software suite), and its temperature performance data is traceable to national metrology institutes (e.g., PTB, NIST) via factory calibration certificates issued with each unit.

Software & Data Management

While standalone operation requires no software, full traceability and automation are enabled via LAUDA’s LabSoft v5.x platform—compatible with Windows 10/11 and validated for FDA 21 CFR Part 11 compliance (electronic signatures, audit trail, role-based access). LabSoft logs timestamped temperature readings at user-defined intervals (100 ms to 60 s), synchronizes with external DAQ systems via TCP/IP or Modbus TCP, and exports raw data in CSV, XML, or PDF report formats compliant with ISO/IEC 17025 clause 7.8. Optional Pt100/LiBus interface module enables closed-loop master–slave configuration with external controllers or centralized lab management systems.

Applications

• Primary and secondary calibration of contact temperature sensors in accredited metrology labs
• Verification of thermocouple wire homogeneity and cold-junction compensation accuracy
• Validation of sterilization autoclave temperature mapping systems
• Thermal characterization of pharmaceutical excipients during stability testing
• Reference bath for thermodynamic property measurement of heat-transfer fluids
• Temperature uniformity assessment of environmental chambers and ovens

FAQ

What is the minimum immersion depth required for accurate calibration?
A minimum immersion depth of 150 mm is recommended for most industrial-grade thermometers; the adjustable overflow ensures this depth remains constant regardless of thermal expansion.
Can the REJ 1225 G be used with silicone oil at 200 °C without degradation?
Yes—the stainless steel bath and sealed cooling circuit are rated for continuous operation with high-temperature silicone oils meeting DIN 51524 Part 2 specifications.
Is remote monitoring possible without purchasing additional hardware?
Basic USB-connected logging is supported out-of-the-box; full remote access (including real-time control and alarm notification) requires either the Ethernet-USB module or LabSoft network license.
Does the unit include a factory calibration certificate?
Each REJ 1225 G ships with a DAkkS-accredited calibration certificate (traceable to PTB) covering three points across the operating range, valid for 12 months from date of dispatch.
How is overtemperature protection configured?
Tmax limit is programmable in 0.1 °C increments via the main menu; activation triggers immediate heater cutoff and audible alarm, with automatic restart inhibited until manual reset.