Touch Current for Exposed Charging Contacts on Bodyworn Medical Device

[cjaldous]

We have a body worn device in development that will use a 4V rechargeable battery, and will recharge in a cradle through surface charging contacts.

In normal use the charging contacts (on the device, connected to the internal battery) will likely make contact with the user's skin. I know that clause 8.4.2(c) is typically used in cases with removable batteries or other exposed contacts that can be avoided and cautioned against, but in this case it would be hard to argue that.

Either we recess the contacts such that they are no longer accessible, or we design some method of protection that would not allow the 100/500uA in NC/SFC. This that correct?

Is there some other way we can approach this?

 

[hcrook]

Is the body-worn device intended to be charged while the patient/operator is wearing it?

You're correct about make the contacts inaccessible or adding a MOP.

 

[cjaldous]

Thanks HC.

The device will be removed from the body and then charged in a cradle.

The cradle will store energy in a lithium ion battery of its own (allowing recharging away from a line voltage source) and will need to be recharged via line voltage (using a wall adapter and usb cable).