Requirement when specifying electrical distribution in
Hospital.
Facility Sizes Flexibility needs emergency power needed safety
requirement
Ground Fault Circuit Interrupter
A device intended for the protection of personnel that functions
to deenergize a circuit or portion thereof within an established
period of time when a current to ground exceeds some predetermined
value that is less than that required to operate the overcurrent
protective device of the supply circuit. Fast acting circuit
breaker Amount of leakage current flowing ~ 5 mA, cause - trip
Isolated Power SystemsTo reduce risk of explosions in OT -
reduces the ignition hazard from arcs or sparks between live and
ground conductor mitigate the hazard of shock or burn from
electrical current flowing through body to ground consists of
isolating transformer, line isolation monitor and ungrounded
circuit conductors
Isolated Power SystemsAdvantages
Reduced shock hazard continuity of supply something for nothing
- noise reduction advance warning of equipment failure
Isolated Power SystemsHow does IPS help to reduce shock
hazard?
Lets consider the normal grounding system, as in figure
above.
Isolated Power SystemsRemember IPS comprised of isolating
transformer, line isolation monitoring, and un-grounded
conductors.
