IEC 60601 Testing - Section 13.2.7 - Impairment of Cooling

[zubangergo]

Hello all,

Do you have any test experience regarding to the section 13.2.7 Impairment of cooling?

We have a straight airflow through a device, and we don't want to use thermal cutoff for overheating. (We want to eliminate the possibility of overheating by redundant ventilation) So we think about a rack mountable design, which has a ventilator on both sides:
_______
| <--- |
|_____|

<-- airflow

The question is, what does "the flow of the cooling agent interrupted" actually means when testing? do they cover all the ventilation holes?
Pushing the device "next to a wall" is ok for us, because the rack mounting edge is lolled out.

We would like to test a device for the 2nd edition, but I have only the 3rd.
Are there any difference?

Please give me your opinion, whether if using a thermal cutoff is obligatory in this case or not..

I'm a 60601 newbie .. thank you in advance!

Gergő

[Pads38]

The test should simulate a 'single fault' so I would look to block one side at a time OR block the top. Then confirm that the hazardous situations (which includes parts exceeding maximum permissible temp) listed in 13.1.2 do not occur.

The test in Edition 2 (Clause 52.5.5) is very nearly identical. With the cutoff date for the use of Edition 2 being just a few months away (Canada and EU) to use it now would be rather short-sighted.

And welcome to the forum.

[zubangergo]

Thank you for your response, You gave the same interpretation, as I thought. Actually we are developing products, which will be connected to medical devices (producing medical systems) and we really want to satisfy the needs of this market, so we decided to take the more strict medical regulations. Our risk management still not prepared enough to meet the requirements of ed 3rd. so until we develop it, we take 2nd ed. as a very first step. Also there is this nrtl mark problem in the states, we can wait the recognition of 3rd.

The real question is that how to manage to keep the temperature low, while the airflow is blocked.
The standard says that the device have to be pushed next to a wall, so i hope that there is a cop-out for us this time - there will be space left for the airflow.

[Carrot.ZHU]

Hello all,
i have a problem to deal with subclause 201.13.2.7 of 80601-2-60 Impairment of cooling that could result in a HAZARD. this is so different from 60601-1's.
descrition: The DENTAL ELECTRICAL MOTOR is held by the OPERATOR'S hand. the loss of cooling results in a slow increase of temperatures so that sufficient time remains for the OPERATOR to react.
how to justify "P" or "N/A" ? Does the manunfacturer need to go with certain kind of test?
i am long for your experienced apply, thank you in advanced.

[Carrot.ZHU]

so discourage, nobody give me responce.

[Stijloor]

In Reply to Parent Post by Carrot.ZHU

so discourage, nobody give me responce.

Vacations and national holiday in the USA.

Please be patient; responses will come...

Stijloor, Forum Moderator.

[Carrot.ZHU]

In Reply to Parent Post by Stijloor

Vacations and national holiday in the USA.

Please be patient; responses will come...

Stijloor, Forum Moderator.

thank you. i forgot it's America Independence day. Appear at the wrong moment.