An electrical protection device including: at least two input terminals for electrically connecting respectively to an active conductor and a neutral conductor of an electrical power source that is upstream of the protection device ; at least two output terminals for electrically connecting to a load having a conductive chassis that is downstream of the protection device , the load drawing a load current; a first sensor for providing a first signal derived from the load current, characterised in that the electrical protection device further includes: a second sensor for providing a second signal derived from a voltage differential between the chassis and a voltage reference; a processing unit that is responsive to a combination of both the first and second signals for selectively generating a fault signal, wherein the processing unit includes a processor that executes a predetermined algorithm which is responsive to the first and second signals for selectively generating the fault signal; and a switching unit that is responsive to the fault signal for progressing from a first state to a second state, wherein: in the first state the input terminals are electrically connected to the output terminals to allow the load current to be drawn from the source to the load ; and in the second state the input terminals are electrically isolated from the output terminals and prevent the load current being drawn from the source to the load . at least two input terminals for electrically connecting respectively to an active conductor and a neutral conductor of an electrical power source that is upstream of the protection device ; at least two output terminals for electrically connecting to a load having a conductive chassis that is downstream of the protection device , the load drawing a load current; a first sensor for providing a first signal derived from the load current, characterised in that the electrical protection device further includes: a second sensor for providing a second signal derived from a voltage differential between the chassis and a voltage reference; a processing unit that is responsive to a combination of both the first and second signals for selectively generating a fault signal, wherein the processing unit includes a processor that executes a predetermined algorithm which is responsive to the first and second signals for selectively generating the fault signal; and a switching unit that is responsive to the fault signal for progressing from a first state to a second state, wherein: in the first state the input terminals are electrically connected to the output terminals to allow the load current to be drawn from the source to the load ; and in the second state the input terminals are electrically isolated from the output terminals and prevent the load current being drawn from the source to the load . a second sensor for providing a second signal derived from a voltage differential between the chassis and a voltage reference; a processing unit that is responsive to a combination of both the first and second signals for selectively generating a fault signal, wherein the processing unit includes a processor that executes a predetermined algorithm which is responsive to the first and second signals for selectively generating the fault signal; and a switching unit that is responsive to the fault signal for progressing from a first state to a second state, wherein: in the first state the input terminals are electrically connected to the output terminals to allow the load current to be drawn from the source to the load ; and in the second state the input terminals are electrically isolated from the output terminals and prevent the load current being drawn from the source to the load . <EOS>