Renal failure therapy system having an electrically floating fluid pathway

A renal failure therapy system comprising:

• a dialyzer;
• a blood circuit in fluid communication with the dialyzer;
• a dialysis fluid circuit in fluid communication with the dialyzer;
• an electrically floating fluid pathway comprising at least a portion of the dialysis fluid circuit, wherein the only electrical path to ground is via used dialysis fluid traveling through the renal failure therapy system to the ground, and wherein at least one electrical component in the at a least portion of the dialysis fluid circuit of the electrically floating fluid pathway is electrically insulated;
• and
• a testing structure configured to test whether the electrically floating fluid pathway has been compromised via an undesired electrical connection to the ground, wherein the testing structure includes a generator selected from the group consisting of a current generator and a voltage generator, and a meter selected from the group consisting of a voltage meter and a current meter,
• wherein the system is programmed to use (i) the generator to set a limit and (ii) the meter to determine if the limit has been reached, and
• wherein the meter is placed in electrical communication with first and second bypasses that shunt current away from the at least one electrical component located in fresh or used dialysis fluid lines of the dialysis fluid circuit.