EIS System Based on Nomex

UL® Recongnized 600 Volt Class Electrical Insulation Systems

Based On NOMEX ® Brand Paper (UL File No.E57692)

NOMEX ® - The Key To Safe, Reliable And Economical Electrical Equipment DuPont was the first material supplier to develop, test and obtain Underwriters Laboratories, Inc. (UL® )* recognition for electrical insulation systems. Now, DuPont offers new UL(& Recognized 600 volt class electrical insulation systems under UL® file number E57692. These systems are shown in Table 1 and are based on NOMEX® brand paper - the key to safe, reliable and economical electrical equipment

Table 1 UL® Recognized 600 Volt Class Electrical Insulation Systems Based On Nomex® (UL® File # E57692)
THERMAL CLASS	CLASS R	CLASS N	CLASS H	CLASS F		CLASS B
THERMAL CLASS	220 oC	200 oC	180 oC	155 oC		130oC
SYSTEM #	10	12	16	14	20	18
GROUND INSULATION	<--------------------------------- Nomex® Brand Paper ------------------------------------------> 5 mil Type 418 5 mil Type 410 7 mil Type 414 7 mil Type E56 7 mil Type 419 10 mil Type 411
MAGNET WIRE	MW 16	MW 35	MW 35	MW 35	MW 24	MW 24
	MW 60	MW 60	MW 60	MW 60	MW 30	MW 30
	MW 61	MW 61	MW 61	MW 61	MW 35	MW 35
		MW 73	MW 73		MW 60	MW 60
		MW 74	MW 74		MW 61	MW 61
						MW 73
					MW 74	MW 74
					MW 76	MW 76
VARNISH	Schenectady Isonel 51	Ripley 468-2	<--------------------OPTIONAL------------------------>**
VARNISH	Schenectady Isonel 51	P.D. George Pedigree 60/60 Polyester DC997

UL® is a certification mark of Underwriters Laboratories, Inc.

DuPont does not recommend using systems without varnish.

The Advantages Of Using A DuPont Insulation System Based On NOMEX® Brand Paper There are several advantages to using an insulation based on NOMEX® brand paper. They include:
Safe And Reliable Operation - NOMEX® is a superior electrical insulation that does not shrink, embrittle, soften or melt during short-term exposure to temperatures as high as 300 o C (570oF), and it maintains good insulating properties even if operated continuously at 220o C (430oF) for 1 0 years. Consequently, NOMEX® extends the life of electrical equipment, reduces failures and repairs, and provides an added safety margin against unforeseen electrical stress situations.

Saves Time And Money - OEM's can save the time and money asso Ciated with obtaining UL® recognition for an insulation system by adopting the DuPont system. OEM's can also cut the cost of ground insulation by taking advantage of the thinner insulation discussed below or by using the more economical NOMEX® Type E56. NOMEX® meets so many insulation needs that it lets OEM's reduce inventory costs by carrying a single insulation material.

Thinner Ground Insulation - The ground insulation thickness in our systems has been reduced to 3 mils of Type 418, 5 mils of Type 41 0 or 7 mils of E56. Due to the potential for the development of partial discharge, particularly at elevated temperatures, DuPont recommends that continuous working stresses at 50/60 Hz do not exceed 40 volts / mil (1.6 kV / mm) rms. In cases where there is high potential for frequent line voltage surges or other abnormal conditions exist, continuous working stresses should be kept below 30 volts / mil (1.2 kV / mm) for maximum equipment life expectancy.

Easy Substitution As Major Insulation - Since NOMEX@ is UL® recognized as a 220 oC material, it is the only sheet insulation that can be easily substituted as major insulation into systems with thermal classes of 22O oC and below. This is true as long as NOMEX® was used as the major insulation during the thermal aging of the system. UL® may require the new types of NOMEX® being substituted in to be thicker than the incumbent material (i.e., if the 60 Hz dielectric strength is lower). For example, UL® usually requires a thicker E56 be used to replace 410. Please consult UL® for the exact substitution requirements. Laminates made with NOMEX® Types 411, E56, 410, 414, 419, and 418 can be easily substituted into systems as major insulation (via sealed tube tests) as long as the total thickness of the NOMEX® meets or exceeds the insulation thicknesses shown in Table 1. For example, a laminate comprised of 5 mils of Type 411, 1 mil of polyester film and 5 mils of Type 411 can be easily substituted as major insulation via a sealed tube test.

Varnish Optional Systems - NOMEX® is such a superior insulation material, that our 220 oC, 180 oC, 155 oC and 130 oC systems have been UL® recognized without varnish. This makes ft easier and more cost effective for OEM's to add the varnish of their choice. Even though varnish is optional, DuPont has added some varnishes to its 220 oC and 18O oC systems. DuPont does not recommend using systems without varnish.

A Complete List Of Minor Insulation Materials - The most widely used tapes, sleevings, tubings, tie cords, spacers, core tubes, and laminates made with NOMEX® have been added to our 220 oC, 200 oC, and 180 oC to ensure our systems meet the needs of our customers.

Adopting Our Systems

It's easy to adopt these systems. As long as the thermal aging of your system can be traced to a DuPont system (UL® file #E57692), the OEM only needs to send a letter to UL® requesting their UL® file be updated to reflect the changes. Otherwise, consult your UL® representative for the best way to take advantage of our systems.


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