Low Operating Temperatures Coupled 

With A Premier Insulation System Heat is the largest factor leading to premature insulation failure - the larger the buffer between the actual motor temperature and the temperature rating of the insulation 

system is, the longer the insulation life will be. 

Hyundai’s approach for a reliable insulation system is to use Class N varnish, which is rated for 200°C and limits the temperature rise to ~74°C. This results in a larger buffer 

between the actual temperature and what the insulation system can handle without 

breaking down. With a 40°C ambient and a motor running at the nameplate load this 

buffer for an HHI motor is a whopping 86°C (200-74-40 = 86). Compare this to a typical 

motor with an 80°C rise and Class F insulation, the buffer is only 35°C (155-80-40=35). 

Remember the old adage, for every 10°C cooler electrical products run, the life expectancy 

of the insulation system doubles. An 86°C buffer is a big deal if you want a motor that will last a long time. 

Summary - Hyundai motors run cooler and provide a larger buffer of protection for the 

insulation system which results in long life. An additional benefit of this design allows 

you to apply a stock motor in higher ambient conditions and still provide a good buffer. Model Number

HHI25-18-575-284THP25 Specifications

RPM 1800

Voltage 575

Frame 284T

EnclosureTEFCFL

Amps (A)24.2

FL Eff (%) 93.6

Approx Wt. (lbs.) 380

Stock Item Delivery is 2 to 5 days from order

 Low Vibration 

Vibration leads to premature bearing failure and can damage the coupled equipment. Hyundai’s approach to a low vibration motor ... Shoot for less than half of the NEMA requirement, don’t cut cost with lighter weight end bells, machine all motors with a precise foot flatness and use only the best bearings. 

NEMA requires a finished motor to have a vibration level that does not exceed .15 inch/second peak. Hyundai’s conservative approach sets the target at ~.07 inch/second peak. All motors are precision balanced, feet are machined to a flatness of ~0.005”, end bells are heavily ribbed and only premium bearings such as NSK, SKF or FAG are used. 

Summary - heavy cast iron frames, precision balance rotors and precise foot flatness leads to lower vibration and thus longer bearing life and less damage to other equipment.