Radiometer Copenhagen CDM 2e Analog Conductivity Meter Micro Milli MHO For Parts

Radiometer Copenhagen CDM 2e Analog Conductivity Meter Micro Milli MHO For Parts

The Radiometer Copenhagen CDM 2e is a benchtop analog conductivity meter designed to measure the electrical conductivity of liquid solutions in both Micro MHO and Milli MHO units. The front panel features a large arc-style moving-needle meter display with dual scales (0–5 and 0–15), a multi-position Measure/Calibrate rotary range selector, a Gx electrode input connector, a Ground terminal, and a 0.2 mA recorder output jack. A U.S.A. Factory Representative nameplate from The London Company (Welwyn International Inc.) of Cleveland, Ohio is affixed to the enclosure, placing this instrument in the mid-20th century era of Scandinavian laboratory instrument manufacturing.

Specifications & What's Included

• Manufacturer: Radiometer Copenhagen (Denmark)
• Model: CDM 2e
• Serial Number: 155098
• Type: Analog conductivity meter
• Display: Moving-needle analog meter, dual-scale arc face (0–5 and 0–15)
• Measurement units: Micro MHO and Milli MHO
• Range selector positions: 1.5 / 5 / 15 / 50 / 150 / 500 (Micro MHO and Milli MHO)
• Recorder output: 0.2 mA
• Front-panel controls: OFF/ON toggle switch, Measure/Calibrate rotary selector, Calibrate knob
• Input connector: Gx electrode input (front panel)
• Ground terminal: Front panel
• Form factor: Benchtop, gray metal enclosure
• Power: Attached round-plug power cable (voltage not confirmed — verify before use)
• U.S. representative: The London Company (Welwyn International Inc.), Cleveland, OH
• Included: Unit with attached power cable
• Not included: Conductivity probe/electrode (not visible in photos)

Applications

Analog conductivity meters like the Radiometer Copenhagen CDM 2e are used in chemistry and biology laboratories to measure the ionic content of aqueous solutions — a proxy for dissolved salt, acid, or base concentration. Common applications include monitoring buffer and reagent preparation, quality control of purified or deionized water, electrochemistry experiments, and environmental water-quality studies. Radiometer Copenhagen, founded in Denmark in 1935, became internationally recognized for precision electrochemical instruments including pH meters, conductivity meters, and titrators; their instruments were a standard fixture in university and industrial research labs from the 1950s through the 1980s. The CDM series meters were distributed in the United States through The London Company (Welwyn International Inc.) of Cleveland, Ohio. This type of analog benchtop meter appeals today to laboratories maintaining legacy instrument setups, collectors of vintage scientific equipment, and technicians sourcing parts for instrument repair.