This steam-powered assembly keeps the temperature in the enclosure within 2 F of the desired control point. However, enclosures may not always provide sufficient protection against the temperature extremes that can affect instrument performance. Temperatures that are too high, for example, can cause some fluids to vaporize. In many cases, the correct temperature of the instrument and sample will affect measurement accuracy. The best way to solve this problem is to equip enclosures with systems designed to maintain interior temperature within the range specified for optimal instrument performance.
Electrical heating can take several forms.
Typically, a radiant heater or heating cable is installed inside the enclosure. A thermostat is used to control temperature or the cable can be self-limiting. However, electrical heating has its limitations. In large installations, the electricity required can be a substantial expense. If combustible substances are present, there is also the risk posed by electrical sparks.