Technical FAQs

Ask a Question

Can wire pulling compound be used for the conductors of an isolated power system?

Issue:
Installation/startup
Product Line:
Hospital Isolated Power Systems
Environment:
NFPA99,NEC517.160
Cause:
Wire pulling compound is commonly used to facilitate the installation of electrical circuit conductors.
Resolution:
NEC 517.160 (A) (6) Wire-Pulling Compounds.  
Wire-pulling compounds that increase the dielectric constant shall not be used on the secondary conductors of the isolated power supply.
Informational Note No. 1: It is desirable to limit the size of the isolation transformer to 10 kVA or less and to use conductor insulation with low leakage to meet impedance requirements.
Informational Note No. 2: Minimizing the length of branch-circuit conductors and using conductor insulations with a dielectric constant less than 3.5 and insulation resistance constant greater than 6100 megohm-meters (20,000M ohm-feet) at 16°C (60°F) reduces leakage from line to ground, reducing the hazard current.
 
Was this helpful?
What can we do to improve the information ?