YVF2 AC Gear Motor – Variable Frequency Three Phase | Speed Control

Product Overview

The YVF2 series variable frequency three phase asynchronous motor is engineered for applications that demand precise, stepless speed adjustment. Derived from the proven Y2 platform (IP54), this AC gear motor pairs a frequency converter drive with a dedicated forced-ventilation cooling system, allowing the unit to sustain rated torque even during extended low-speed operation. With frame sizes spanning 80 mm to 355 mm and output ratings from 0.55 kW up to 315 kW, the YVF2 line covers virtually every mid-range industrial drive requirement.

Originally developed as a direct replacement of Y2-based frequency-controlled drives, the YVF2 motor has found widespread adoption across light manufacturing, metallurgy, textile processing, and chemical handling facilities. The motor accepts input frequencies between 5 Hz and 100 Hz, yielding a speed adjustment window that satisfies most conveyor, pump, and fan applications. For operations in Korea and neighboring markets, the YVF2 offers a cost-effective path to variable-speed automation without sacrificing build quality or thermal reliability. Class F insulation and a standard IP54 enclosure ensure safe, long-term performance in dusty or moderately damp environments.

 

Facilities currently running older frequency-regulated electric motor units — including legacy imports — can drop in the YVF2 with minimal wiring changes. The shaft dimensions, flange patterns, and terminal layouts follow IEC standards, so mechanical interfacing is straightforward. Whether you need a single replacement unit or a bulk order for an entire production line, this motor series delivers repeatable, measurable energy savings through precise converter-based speed control.

 

Technical Specifications

Below is a summary of the operating parameters for the YVF2 series. All ratings are measured at 380 V, 50 Hz base frequency with Class F insulation and IP54 protection.

The detailed performance table lists each model variant with its rated current, torque ratio, efficiency, power factor, and matching inverter capacity. Scroll horizontally on smaller screens to view all columns.

Note: Full technical data covering 2-pole, 4-pole, and 6-pole variants is available upon request. All values measured at 380 V / 50 Hz base frequency.

YVF2 Series Frequency Controlled Three Phase Asynchronous Motor B5 Installation Dimension

YVF2 Series Frequency Controlled Three Phase Asynchronous Motor B3 Installation Dimension

YVF2 Series Frequency Controlled Three Phase Asynchronous Motor B35 Installation Dimension

Model No.	Installation size  mm
	H	A	B	C	D		E		FXGD		G		K	T	M	N	P	R	S
					2Poles		2 Poles	4.6.8 Poles	2 Poles	4.6.8 10 Poles	2 Poles	4.6.8 10 Poles
80	80	125	100	50	19		40		6×6		15.5		10	3.5	165	130	200		4-φ12
90S	90	140		56	24		50		8×7		20							0
90L			125
100L	100	160	140	63	28						24		12	4	215	180	250		4-φ15
112M	112	190		70			60
132S	132	216		89	38		80		10×8		33				265	320	300
132M			178
160M	160	254	210	108	42		110		12×8		37		15	5	300	250	350		4-φ19
160L			254
180M	180	279	241	121	48				14×9		42.5
180L			279
200L	200	318	305	133	55				16×10		49		19		350	300	400
225S	225	356	286	149			110	140	16×10	18×11	49	53			400	350	450		8-φ19
225M			311		55	60					53
250M	250	406	349	168	60	65	140		18×11		58	58	24		500	450	550
280S	280	457	368	190	65	75			18×11	20×14		67.5
280M			419
315S	315	508	406	216		80	140	170		20×14		71	28	6	600	550	660		8-φ24
315M			457
315L			508
355M	355	610	560	254	75	95			20×12	25×14	67.5	86			740	680	800
355L			630

How the YVF2 Variable Frequency Motor Works

A variable frequency AC gear motor relies on a frequency converter (also called a VFD — variable frequency drive) to adjust the power supply frequency fed to the stator windings. Because the synchronous speed of any three phase motor is directly proportional to supply frequency, changing the frequency changes the rotational speed. The YVF2 series accepts input frequencies between 5 Hz and 100 Hz, which translates to an operating speed window that can range from roughly 5 % of nominal speed all the way up to double nominal speed.

Internally, the motor shares a conventional squirrel-cage rotor architecture with the Y2 platform: copper or aluminum bars are cast into slots in the laminated rotor core and short-circuited at both ends by end rings. The stator carries a three-phase distributed winding wound with Class F insulation wire. When an alternating current at a given frequency energizes the stator, a rotating magnetic field is produced in the air gap. The rotor conductors cut through this field, inducing currents that generate torque and spin the shaft.

What distinguishes the YVF2 from a standard fixed-speed induction motor is the independent cooling fan. On most general-purpose motors, the cooling fan sits on the shaft itself — so at low speeds the fan turns slowly and airflow drops. The YVF2 solves this with a separately powered axial fan (IC416 cooling arrangement) that provides constant airflow regardless of rotor speed. This design feature is what allows the motor to carry full load continuously at speeds well below its rated point without overheating the windings or bearings.

Core Advantages of the YVF2 AC Gear Motor

The YVF2 platform brings together several design strengths that matter to maintenance teams and procurement managers alike. Below are the key benefits explained in practical terms.

◆ Wide, Smooth Speed Range — Operating between 5 Hz and 100 Hz gives a continuous adjustment band from near standstill to twice the base speed. There are no mechanical steps or clutch transitions. Conveyor systems, mixers, and blowers all benefit from this kind of throttle control because process parameters can be tuned in real time rather than fixed at installation.

◆ Constant-Torque Low-Speed Operation — The IC416 independent fan keeps winding temperatures within spec even at 10 % of rated speed. Plants that run batch processes — where a motor might idle at low speed for hours between bursts — will see measurably lower bearing wear and insulation degradation compared to standard self-cooled designs.

◆ Energy Savings Through Converter Control — Matching motor speed to actual load demand (rather than running full speed and throttling output mechanically) can cut electricity consumption by 20 % to 40 % on fan and pump duty cycles. Over a 5-year service life, this translates to a payback period of well under two years for most installations.

◆ Low Noise and Vibration — Precision-balanced rotors and tight machining tolerances keep vibration below the IEC 60034-14 Grade A limit across the entire speed range. Workers on the factory floor notice the difference, and sensitive downstream equipment such as optical inspection stations or weighing cells benefits from reduced mechanical disturbance.

◆ IEC-Standard Dimensions — Frame sizes, shaft diameters, and mounting foot patterns comply with IEC 60072. Existing mounting plates, couplings, and alignment shims designed for Y2 or equivalent motors will work without modification.

Selection Guide for Variable Frequency AC Motors

Choosing the right model from the YVF2 catalog means matching several parameters to your application at the same time. Getting the power rating right is only the starting point; operating conditions, duty cycle, and inverter compatibility all play a role. Here is a practical walkthrough of the key factors to confirm before placing an order.

Required Output Power and Speed

Start with the torque and speed your driven equipment actually needs — not the nameplate of the motor it currently uses, which may have been oversized years ago. Calculate the required shaft torque at the target speed and pick a motor whose rated torque at that same speed (as listed in the specification table) exceeds your requirement by at least 15 %. This margin covers power factor variation, altitude derating, and normal measurement uncertainty. For constant-torque loads such as conveyors and extruders, choose based on the full-load torque at minimum operating speed. For variable-torque loads like centrifugal fans, the required torque at maximum speed is typically the governing factor.

Inverter Matching

Every model in the YVF2 table lists a recommended inverter capacity in kilowatts. Always match or slightly exceed this value when sourcing the VFD. Under-sizing the inverter causes nuisance trips under transient loads; over-sizing wastes capital and cabinet space. If you plan to run extended periods above 50 Hz (field weakening region), confirm that both the inverter and the motor bearing arrangement can handle the elevated speed. The full range of compatible AC gear motor with speed control configurations is listed in our product catalog.

Installation Environment

Standard YVF2 motors are rated for ambient temperatures up to 40 °C and altitudes up to 1 000 m. If your plant sits at a higher elevation or in a hotter climate, request a derating table from our engineering team. For environments with aggressive dust, chemical vapors, or high-pressure washdown requirements, ask about the IP55 upgrade. The independent cooling fan draws air from outside the motor casing, so ensure the air intake side faces away from concentrated heat sources or steam vents.

YVF2 vs. Comparable Imported Models

Disclaimer: We mention third-party brand names solely to help customers with cross-referencing and product selection. Korea Ever-Power PTO Shaft Co., Ltd does not sell, distribute, or represent these brands. Our products are independently manufactured and are not affiliated with, endorsed by, or connected to any of the brands referenced below.

The YVF2 delivers comparable electrical performance to most mainstream imported VFD motors while offering a clear price advantage and shorter delivery windows to the Korean peninsula. For facilities managing tight maintenance budgets, stocking replacement YVF2 units is significantly more economical than holding inventory of premium-brand equivalents.

Related and Complementary Products

A variable frequency motor rarely operates in isolation. It sits at the heart of a drive train that may include speed reducers, couplings, chains, and other transmission components. Korea Ever-Power carries a broad catalog of complementary mechanical products designed to work alongside our ac motors lineup.

When a direct-drive setup does not provide enough torque at the shaft, pairing the YVF2 with a worm gear reducer can multiply output torque while reducing speed mechanically — complementing the electronic speed regulation of the VFD. For higher efficiency at moderate reduction ratios, a planetary gearbox is the preferred option: its compact, coaxial design keeps the drive train short and avoids the axial offset inherent in worm sets.

Power transmission between shafts that are not directly coupled often relies on sprocket and chain assemblies. These are commonly used on conveyor lines, packaging machines, and agricultural equipment where the motor and the driven shaft are not aligned end to end. Flexible jaw couplings, rigid flanged couplings, and disc couplings are all available for connecting the YVF2 output shaft to gearboxes, pumps, or directly to the load.

Frequently Asked Questions

Can the YVF2 motor run on 440 V or 480 V three-phase power common in Korean industrial facilities?
Yes. While the standard catalog voltage is 380 V, we manufacture custom-wound versions for 400 V, 440 V, and 480 V supplies. Specify the target voltage when placing your order and allow approximately 3 extra working days for winding adjustment.

What type of frequency inverter should I pair with this variable speed ac gear motor?
Any general-purpose V/f or sensorless vector VFD rated at or above the inverter capacity listed in our specification table will work. For applications that require high torque at very low speeds (below 5 Hz), consider a closed-loop vector drive with encoder feedback for the best performance.

How often should the independent cooling fan motor be serviced?
Under normal conditions (ambient temperature below 35 °C, moderate dust), inspect the fan motor bearings and clean the air filter screen every 4 000 operating hours. Replace the bearing grease every 8 000 hours or once per year, whichever comes first.

Is the YVF2 motor suitable for outdoor installation?
The IP54 rating protects against dust ingress and water splashes from any direction, so a sheltered outdoor location is acceptable. For fully exposed installations without a rain canopy, we recommend upgrading to IP55 and fitting a shaft seal kit to prevent moisture from entering along the output shaft.

What is the expected bearing life on the YVF2 at full load and rated speed?
The standard bearing configuration (6205–6316 series depending on frame size) provides a calculated L10 life of 20 000 hours at rated load and speed. Proper lubrication intervals and correct belt tension (if belt-driven) will extend actual service life well beyond this figure.

Can I use this motor for applications that need frequent start-stop cycles?
Frequent starting via the VFD is gentler on windings than direct-on-line starting because the inverter ramps current gradually. The YVF2 handles thousands of start-stop cycles per day without issue. However, if you need mechanical braking between cycles, consider the YEJA series with a built-in electromagnetic brake.

Do you offer technical drawings and 3D models for the YVF2 frame?
Yes. DXF outlines and STEP files for all frame sizes are available on request. Send your model number to our engineering team and we will provide the files within one business day.

Customer Reviews

Kim Tae-won, Plant Manager, Incheon (early 2025)
"We replaced eight imported motors on our coating line with YVF2-160M2-2 units last January. Installation took one afternoon because the bolt pattern is identical. The electricity bill for that line dropped noticeably by the second month. Ordering process was simple and the crate packaging arrived in perfect condition."

---

Park Joon-ho, Maintenance Engineer, Busan (mid 2024)
"We had an emergency breakdown on a 7.5 kW pump drive. I called Ever-Power on a Monday, the YVF2-132S2-2 motor shipped Tuesday, and it was running by Thursday. The vibration readings on the new motor are actually lower than the old one it replaced. Good motor, fast service."

---

Lee Soo-jin, Procurement Director, Gyeonggi-do (late 2024)
"Price-to-performance ratio is hard to beat. We have been buying these for our conveyor upgrades. Six units installed over the past year, zero failures so far. The sales team answers technical questions quickly, which our engineers appreciate."

---

Choi Min-seok, Technical Director, Ulsan (early 2025)
"Tested the YVF2-200L1-2 on a 30 kW blower for three months before committing to a larger order. Efficiency at 40 Hz was about 1 percentage point below the catalog figure, which is within measurement tolerance. Cooling fan is noticeably quieter than expected. We have since ordered twelve more for a new plant expansion."

---

Jung Ha-na, Equipment Manager, Daegu (mid 2025)
"The motor runs a kneading machine in our food processing workshop. Needed something that could handle frequent speed changes without overheating. The YVF2 holds temperature well even during long slow-mix cycles. The stainless steel nameplate is a nice touch for our food-safety audits."

---

Shin Hyun-woo, Project Engineer, Changwon (late 2024)
"Honestly, I was skeptical about switching from our usual European supplier. The YVF2 spec sheet looked comparable so we tried two units on a test bench. After 2 000 hours of run time the winding resistance and insulation readings are right where they should be. Cannot justify paying double for the European brand anymore."

Packing and Shipping