NEMA LI 1-1998
National Electrical Manufactures Association
NEMA LI 1-1998 is the most widely used standard for thermoset composites in sheet, tube, and rod forms in the United States.
NEMA LI 1-1998 “Industrial Laminated Thermosetting Products” was revised in 1998 to mirror MIL-I-24768 with the intention of replacing this Military Specification.
The NEMA Standard provides generic category recognition of grades based on their construction, reinforcement, and resin. Typical properties for each category are defined and published along with standard dimensional tolerances for standard forms of the product. NEMA provides one of the most basic standards for thermoset materials and is often enhanced with customer specific specifications or additional criteria from another standard.
Sheet Grades
| Grade Type | Description | Norplex-Micarta Grades |
|---|---|---|
| Fr-4 (see note) | epoxy glass flame retardant | GSFR4 GSFR4A NP130 NP130HF NP506A NP510A NP510WR |
| Fr-5 | epoxy glass flame retardant high temperature | MC511FR NP513FR |
| G-3 | phenolic glass | NP504 NP515LS |
| G-5 | melamine glass | NP509 |
| G-7 (see note) | silicone glass | MC507U |
| G-9 | melamine glass | NP509 |
| G-10 | epoxy glass | NP500A |
| G-11 | epoxy glass high temprature | MC511A MC511AF NP511 NP511EM NP572 |
| C | phenolic canvas | GSC NP310 NP310HT NP342 |
| CE | phenolic canvas electrical grade | GSCE NP310E |
| L | phenolic linen | NP320 |
| LE | phenolic linen electrical grade | MC320LE NP320E |
| X | phenolic paper | NP610 |
| XP | phenolic paper punching grade | NP611 NP660 |
| XPC | phenolic paper cold punching grade | NP612 NP625 |
| XX | phenolic paper | NP629 |
| XXX (see note) | phenolic paper | NP630 |
| N-1 | phenolic nylon | NP101 |
MC507U, MC511FR, NP510WR, and NP630 does not meet all of the properties of their corresponding NEMA grades. Please refer to the technical data bulletins and contact Norplex-Micarta for further details.
Convolute Wound Tube Grades
| Grade Type | Description | Norplex-Micarta Grades |
|---|---|---|
| Fr-4 | epoxy glass flame retardant | RT130 RT130M RT130X |
| G-3 (see note) | phenolic glass | RT504 RT504M RT504F |
| G-5 | melamine glass | RT505 RT505F |
| G-7 | silicone glass | RT507 RT507F |
| G-9 | melamine glass | RT509 RT509F |
| G-10 | epoxy glass | RT500 RT500F RT500M RT500X RT571 |
| G-10 High Temperature “G-11” (see note) | epoxy glass high temperature | RT511 RT511F RT511H RT511M |
| C | phenolic canvas | RT310 RT310H RT310S RT342 |
| LE | phenolic linen | RTB320 RTB320H RTB320X RTB320Z |
| X | phenolic paper | RT610 |
| XX | phenolic paper | RT628 RT628H RT629 |
| XXX | phenolic paper | RT630 RT630H |
Although G-3 tubing grades are recognized by NEMA, ASTM and MIL-I-24768 standards as a material form, property requirements are undefined at this time.
NEMA Standard LI 1-1998 and MIL-I-24768 do not recognize a high temperature epoxy glass convolute rolled tube form, but, these materials are manufactured with a high temperature epoxy resin system, commonly used for NEMA G-11 and MIL-I-24768/27, type GEB sheet products, and do have improved thermal properties at elevated temperatures.
Rolled and Molded Rods
| Grade Type | Description | Norplex-Micarta Grades |
|---|---|---|
| Fr-4 | epoxy glass flame retardant | RM130 |
| G-3 | phenolic glass | RM504 |
| G-5 | melamine glass | RM505 |
| G-10 | epoxy glass | RM500A |
| G-10 High Temperature “G-11” (see note) | epoxy glass high temperature | RM511A |
| C | phenolic canvas | RM310 |
| CE | phenolic canvas | RM310E |
| L | phenolic linen | RM320 |
| LE | phenolic linen electrical grade | RM320LE |
| XX | phenolic paper | RM629 |
| XXX | phenolic paper | RM630 |
NEMA Standard LI 1-1998 and MIL-I-24768 do not recognize a high temperature epoxy glass convolute rolled rod form, but, these materials are manufactured with a high temperature epoxy resin system, commonly used for NEMA G-11 and MIL-I-24768/27, type GEB sheet products, and do have improved thermal properties at elevated temperatures.