Patent ID: 6225610
Filing Date: 2001-05-01
Classification: B60R,H02H

Abstract:
An electrical circuit which has a maximum steady state current under normal operating conditions I.sub.LOAD and which comprises(1) a source of electrical power;(2) a PTC protection device having a pass current I.sub.PASS and a trip current I.sub.TRIP and containing a PTC element which is composed of a conductive polymer exhibiting PTC behavior;(3) an operative electrical device which is spaced apart from the PTC protection device; and(4) an insulated electrical wire which has a damage current I.sub.DAMAGE and which connects the PTC device to the operative electrical deviceand in which(a) at each temperature within a range T.sub.1 to T.sub.2, where T.sub.1 is 0.degree. C. and T.sub.2 is 80.degree. C.,(i) I.sub.PASS is at least 1.1 times I.sub.LOAD and(ii) I.sub.DAMAGE is at least 1.1 times I.sub.TRIP ;(b) at at least one temperature within the range T.sub.1 to T.sub.2, I.sub.PASS is at most 1.5 times I.sub.LOAD ; and(c) at at least one temperature within the range T.sub.1 to T.sub.2, I.sub.DAMAGE is at most 1.5 times I.sub.TRIP.