Ismet three-phase sine filter UAF/1/85 is easy to install and maintain

Ismet three-phase sine filter UAF/1/85 is easy to install and maintain

UAF/1/85 is a universal sine filter designed by Czech Ismet specifically for 0.1-4 kW low-voltage frequency converters, with a rated line voltage of 400 VAC and a continuous current of 85 A. It is installed between the output terminal of the frequency converter and the motor, converting PWM pulse voltage into an approximately ideal sine wave, significantly reducing harmonics, du/dt, and electromagnetic interference.

Core Structure and Parameters

• Filter topology

- Three phase symmetrical LC low-pass, with independent inductance and X2 safety capacitor for each phase;

The cut-off frequency is 2.5 kHz, much lower than the typical PWM carrier of 8-16 kHz, and higher than the fundamental wave of 50/60 Hz, ensuring zero attenuation of the fundamental wave and high attenuation of harmonics.

• Key components

Iron core: low loss oriented silicon steel sheet, vacuum impregnated with H-grade paint;

- Inductance value: 1.2 mH ± 5% per phase;

- Capacitor: 3 × 10 µ F/440 VAC, self-healing metalized film;

Peak dv/dt suppression: ≤ 500 V/µ s (measured under a 380 V system).

• Electrical specifications

Rated current: 85 A (continuous at 40 ° C);

Overload capacity: 150% 60 s, 200% 3 s;

- Protection: IP00 modular or IP20 sheet metal shell optional;

- Certification: CE, UL, EN 61800-5-1.

working principle

The frequency converter outputs high-frequency PWM → the filter inductor blocks high-frequency current → the capacitor provides a low impedance path for high-frequency → the residual fundamental current drives the motor almost without distortion. Result:

The voltage THD has decreased from 35% to<5%;

Shaft current and bearing erosion decrease by 80%;

Reduce motor noise by 6-10 dB.

Typical returns

Extend the insulation life of the motor: After du/dt decreases, the starting voltage of partial discharge increases by 25%;

Worry free for long cables: No need to output reactors within 300 meters;

• Meet the EMC: CISPR 11A industrial conduction and radiation limits with a single pass.

Installation and maintenance

Directly connect U/V/W three-phase without additional cooling;

Equipped with an NTC 130 ° C temperature switch, it can be connected to the driver's "external fault" input;

• It is recommended to install vertically, leaving ≥ 100mm air ducts above and below.

Application scenarios

Energy saving renovation of fans, water pumps, and compressors;

High speed spindle, machine tool feed servo;

Hospitals or laboratories are sensitive to EMI in certain areas;

Port crane, long cable reel drive.

Technical Specifications:

910-941

UAF/1/85

690V 3~70Hz 1,5kHz

ta40°C EIS155 IP00

Three phase sine filter

Three phase sine filter

Voltage: 690V

Current: 1A

Inductance: 85mH

Frequency: 3~70Hz

Switching frequency. /Frequency: 1,5kHz

Environmental temperature: ta 40/F

Protection level: IP00

Cooling: AN

Origin: Czech Republic

Ismet three-phase sine filter UAF/1/85 is easy to install and maintain