Temperature rise as K? & ANSI/UL 875 1

[Jakelian]

Dear users, I have two questions:

1. In several places of the heating sections of Euro (EN) standards, there are several tables showing temperature rise as K. For example: "During normal operation, the temperature rise of the applience's walls shall not exceed 140 K". What does 140 K mean??

2. Why it says ANSI/UL 875 - Electric Dry Bath Heaters for this standard? I mean, ANSI and UL at the same time? WHat does ANSI have to do with that?

Thanks!

 

[FrenchCAD]

K stands for Kelvin. Typically, 1°K = 1°C, just that 0°K is absolute zero in °C, i.e. -273 °C. Look for Kelvin in Wikipedia.

Cyril Guichard
Defense Program Manager
Belgium

 

[Jakelian]

Dear FRENCHCAD,

Thanks a lot for your time and answer, see, I am not an engineer, but involved in the design of the product. I need to simplify the item; I need to know the max allowed temp on that part. so,

In this case, if max temp rise allowed on the body part is 140 K, can I take it like:

Max allowed temp on that part is 140 C? or,

Max allowed increase (diffrence) on that part is 140 C?

or any other C value?

Thanks again!

 

[FrenchCAD]

as it sates "temperature rise", it means that your temperature increase is acceptable up to 140°C (delta temperature between min and max)

Cyril Guichard
Defense Program Manager
Belgium

 

[JLSeagull]

Degree K
Absolute temperatures apply when used for calculations. Zero degrees Kelvin is absolute zero. If you do percentage calculations from using degree C thus somewhere in the mid point as zero the results would be wrong as 0 degree C is 273 degree K.

UL/ANSI
Many US agencies were listed by ANSI if generally accepted as a consensus standard. This was significant for legal enforcement. With efforts to coordinate the international standards ANSI is becoming insignificant. Agencies such as UL are not government entities. UL is commercial and mostly applies to electrical appliances but continues to broaden in scope. ASME is like an engineering club that establishes good mechanical engineering criteria.