A
antonoia
Hi All, I would like to hear your opinions and help me to clarify some doubts of some 60601-1 clauses.
We have a device, class 2 metallic enclosure with a PSU already having 2MOOP, secondary at 12Vdc that goes to some internal circuits.
According clause 8.9.1.12, where a secondary is not earthed and derived from Supply Mains, the circuit shall be subjected to the requirements for primary circuit in table 13 and 14. Clause 8.9.1.12 also states ?a secondary circuit derived from a supply mains will normally be overvoltage category I according to IEC 60664-1 if the mains part is overvoltage category II?. Table 13 starts with a voltage of 210V dc, would I consider this for my small 12 Vdc towards accessible parts? If my understanding is correct , should I select the value form the column ? Nominal mains Voltage <150V?? ( even I still have a mains of 240Vac) but just because this column contains ?(Mains transient Voltage 1500V)? ? In this case I should provide 2mm (2MOOP overvoltage cat.II). Am I correct?
And for the test voltage according table 6 seems will not be required between my secondary circuit of 12Vdc inside the device and the accessible parts. Table 6 says no test for voltage below 60Vdc, but table 7 provides test voltage also for 34Vdc, I did not understand here, one table says no test for voltage below 60Vdc while the other one expects test for 34Vdc. Could you please light up me from the darkness around this controversy? What is the minimum values for a dc so will not be required test for protection from secondary circuits?
I will like also to talk about clause 8.4.2 ?Accessible parts and applied parts? since seems to fall on same arguments of above. Here are given limit values of 60Vdc and 42.4Vp, same starting values of table 6. Are this two clause is some way related? For my understandings after all see clause 8.1, we can have a device that have high voltage on accessible parts, clearance and creepage not satisfying requirements, important are leakage currents are whiting the give limits? Is all about the requirement of 60601-1 ? leakage currents? Thank you and sorry for been so dispersive!
We have a device, class 2 metallic enclosure with a PSU already having 2MOOP, secondary at 12Vdc that goes to some internal circuits.
According clause 8.9.1.12, where a secondary is not earthed and derived from Supply Mains, the circuit shall be subjected to the requirements for primary circuit in table 13 and 14. Clause 8.9.1.12 also states ?a secondary circuit derived from a supply mains will normally be overvoltage category I according to IEC 60664-1 if the mains part is overvoltage category II?. Table 13 starts with a voltage of 210V dc, would I consider this for my small 12 Vdc towards accessible parts? If my understanding is correct , should I select the value form the column ? Nominal mains Voltage <150V?? ( even I still have a mains of 240Vac) but just because this column contains ?(Mains transient Voltage 1500V)? ? In this case I should provide 2mm (2MOOP overvoltage cat.II). Am I correct?
And for the test voltage according table 6 seems will not be required between my secondary circuit of 12Vdc inside the device and the accessible parts. Table 6 says no test for voltage below 60Vdc, but table 7 provides test voltage also for 34Vdc, I did not understand here, one table says no test for voltage below 60Vdc while the other one expects test for 34Vdc. Could you please light up me from the darkness around this controversy? What is the minimum values for a dc so will not be required test for protection from secondary circuits?
I will like also to talk about clause 8.4.2 ?Accessible parts and applied parts? since seems to fall on same arguments of above. Here are given limit values of 60Vdc and 42.4Vp, same starting values of table 6. Are this two clause is some way related? For my understandings after all see clause 8.1, we can have a device that have high voltage on accessible parts, clearance and creepage not satisfying requirements, important are leakage currents are whiting the give limits? Is all about the requirement of 60601-1 ? leakage currents? Thank you and sorry for been so dispersive!