IEC 60601-1 Testing required for low-voltage devices?

[mimic]

Hi Everyone,

Our medical device company is currently in the process of creating a device which can be classified as a INTERNALLY POWERED ELECTRICAL EQUIPMENT. The device is powered by three 3V coin cell batteries which form part of the the ME Equipment.

I have read through the IEC 60601-1 (tried to atleast) and there is a plethora of electrical testing.

My initial reaction is that for such a low-voltage battery, the risks are minimal and the filters of IEC 60601 are not designed for this device and therefore is not relevant.

Any IEC 60601 experts out there who can guide me through this standard.

Is the electrical testing relevant for such a device? I have tried to find clauses in the standard which would dictate the minimum voltage for an Internally Powered Equipment that can be tested by this standard but haven't found any information.

Using a worst case scenario, imagine a medical device that is only three 3v coin cell batteries stacked on top of each other with leads sticking out of them. You can consider the leads sticking out as the APPLIED PARTS. Essentially a 9v battery which is being considered here as a medical device. Would any of testing in IEC 60601 help?

Any help would be greatly appreciated!.

Thank you

edited: Leads defined as APPLIED parts

 

[Marcelo]

As weird as it seems, IEC 60601-1 is still applicable to this kind of equipment.

As you noted, there´s no exemption for minimum voltage (and if there was, it would be in the scope).

Surely a lot os tests would not be applicable in different cases, but it´s also not very clear which ones would not.

Finally, what exactly is the problem? Standards are generally voluntary, so if you do not want to apply it, generally you can (but you surely would need a good justification).

 

[Peter Selvey]

For a device like this there remains some simple and reasonable requirements you should check:

- labelling (6) - external/internal & instructions for use
- battery insertion: what happens if reversed (56.something)?
- battery short: any problems (52.5.9)

There are some agencies that may go to town on patient isolation, leakage currents, dieletric strength but none of this is justified based on the fundamentals.

3Vdc can be potentially dangerous in the following condition:
- applied directly to a patient with low impedance
(e.g. metal/gel electrodes)
- applied for a long period

In this case "dc burns" may occur which are not very nice.

But all electrical current through a patient requires 2 points (in and out), the probability of these conditions occuring at both sites is non-existent for most 3V types of devices that I know of.

You are probably stuck sequentially checking all of the ~500 requirements from IEC 60601-1 just to be sure, but around 98% will be not applicable.

Peter