Technical FAQs

Ask a Question

When testing the voltage of a (typically 120V) hospital isolated power system, why am I not getting 120V to ground?

Issue:
When testing the voltage of a (typically 120V) hospital isolated power system, why am I not getting 120V to ground?
Product Line:
Hospital Isolated Power Systems
Environment:
NFPA99, NEC517.160
Cause:
Product Design

Resolution:
A hospital isolated power system is an ungrounded system, and for this reason, one should not anticipate the measured voltage between ground and either line to be 120V.  In practice, one should expect to read about 50% of the system voltage from either line to ground.
Was this helpful?
What can we do to improve the information ?