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Sigma Frequency Converter

Kaeser’s Sigma Frequency Control (SFC) compressors combine our Sigma Profile airends and revolutionary Sigma Control system with the latest in variable speed drive technology. Kaeser uses large, optimized airends turning at slower speeds for more efficient performance across the entire speed range.

Soft starts

SFC units go from zero to full load without current spikes or excess heat rise. This allows unlimited motor starts, and since the SFC drive yields a “near unity power factor,” power factor penalties are also eliminated.

Specifications

  • Horsepower: 25-450 hp
  • Capacities: 72-2015 cfm
  • Standard pressures 80-217 psig

Precise pressure control

SFC compressors precisely control system pressure to ±2 psig using highly accurate sensors and the Sigma Control System to control motor speed. This eliminates “overpressurizing” and increases energy savings – after all every 2 psig saved in overpressurizing reduces power consumption by 1%!

Superior frequency drive system technology

SFC drive systems feature electromagnetic interface (EMI) filters, contactors for galvanic separation and line reactors for superior protection. Drive cabinet cooling fans maintain proper operating temperatures even under extreme ambient conditions.

EMI filter

SFC drive systems are designed with an electromagnetic interference filter that eliminates or isolates all feedback, and prevents harmonic distortion from entering the plant’s electrical grid.

No Model Rated Motor Power Min. Capacity at 460V, 110 psig Max. Capacity at 460V, 110 psig
1 SFC 8 / 8T 10 hp 13 cfm 48 cfm
2 SFC 11 /11T 15 hp 22 cfm 76 cfm
3 SFC 15 / 15T 20 hp 29 cfm 102 cfm
4 SFC 18S /18ST 25 hp 33 cfm 127 cfm
5 SFC 22S / 22ST 30 hp 33 cfm 149 cfm
6 SFC 22 / 22T 30 hp 36 cfm 166 cfm
7 SFC 30S / 30ST 40 hp 37 cfm 182 cfm
8 SFC 30 / 30T 40 hp 46 cfm 213 cfm
9 SFC 37 / 37T 50 hp 54 cfm 254 cfm
10 SFC 45S / 45ST 60 hp 69 cfm 288 cfm
11 SFC 45 / 45T 60 hp 69 cfm 310 cfm
12 SFC 55 / 55T 75 hp 77 cfm 374 cfm
13 SFC 75S / 75ST 100 hp 100 cfm 463 cfm
14 SFC 90S / 90ST 100 hp 120 cfm 509 cfm
15 SFC 110S / 110ST 125 hp 136 cfm 618 cfm
16 SFC 75 / 75T 100 hp 127 cfm 559 cfm
17 SFC 90 / 90T 125 hp 127 cfm 627 cfm
18 SFC 110 / 110T 150 hp 150 cfm 735 cfm
19 SFC 132S / 132ST 175 hp 209 cfm 830 cfm
20 SFC 132 200 hp 209 cfm 919 cfm
21 SFC 160 250 hp 230 cfm 1074 cfm
22 SFC 200 270 hp 303 cfm 1305 cfm
23 SFC 250 340 hp 358 cfm 1466 cfm
24 SFC 315 450 hp 470 cfm 2091 cfm
25 SFC 515 590 hp 413 cfm 2624 cfm
26 SFC 515 700 hp 417 cfm 3037 cfm