@che12345 Apologies for the late response. However, do we have any citation, to prove otherwise (+/- 5K violation is permissible). I really need it because upon checking on Stack Exchange, I got a different response...
-@che12345. FYI, I found the formula in Copper Development Association Publication No. 22, Ed. 14th - 1996 and it's been referred in IEC 61439-1. However, the CDA, does not mentions the condition of +/-5K. IEC 61439-1 does mentions the condition, as mentioned by you, to stop abuse of the formula.
Hello @che12345
Thank you for your response.
Please find below response to your answer.
1. The formular is applicable up to (the temperature deviation from the [permissible value] by not more than +- 5K).
The key word is [permissible value]. That is, it is applicable for any value lower than...
@NickParker.
You can disable the G function of the LSIG. But make sure that the earth leakage relay that you are intending to use should be wired to the shunt trip (or likewise) of your incomer. This will ensure that if 5A of the current flows through the earth circuit, the shunt trip will open...
I was referring IEC 61439-1 standard for the deriving the temperature rise of an assembly through comparison. We can derive the current rating of an assembly (low voltage switchboard) at any point (contacts such as busbar joints, SCPD joint, or any other contact) by using the formula of Copper...
@che12345 ,
Thanks for your response. The values are based on ambient of average 350C and peak 400C.
Also, I have mentioned the temperature values for ACB-copper joint. The ACB is covered by IEC 60947-2 and it states that the max. temperature rise should not exceed 80K.
As per your response...
@Gr8blu
Thanks for writing. However, if I go word by word, the IEC haven't mentioned about TWO consecutive measurement interval. The one measurement interval (i.e. per hour) is sufficient to establish that the temperature is constant on the reasonable assumption that the range will only be...
I am trying to understand a temperature rise test that is being conducted over a switchboard. The test conforms to IEC 61439-1. The clause 10.10.2.3.1 (Method of test - General) regarding the temperature rise states about the constant value. It says,
"The constant value is reached, in practical...
