Suppressors API newlayouts single:APIcatalog newlayouts 8/27/10 10:01 AM Page 118 BF SERIES Split Ferrite Suppressors for Round Cables Actual Size (BF2125) Electronic cables and wires, by virtue of their length-to-width POSITION OF SUPPRESSOR The suppressor should normally ratios, are perfect natural antennas. In the presence of high be located close to the cable termination where it exits the speed microprocessor signals, cables will conduct, radiate enclosure. Where a cable connects two enclosures containing RF and/or receive unwanted high frequency interfering signals. sources, a suppressor on each end may be required. For circuits Radio interference sources usually radiate their RFI power at within an enclosure, a position close to the RF is best. However, frequencies above 30 MHz by way of the main cabling, which other locations along the circuit may work as well. acts as an antenna. Control of radio interference can be Material and U.L. Data API-1 Material, see characteristics and assured by proper placement of an insertion loss device, such information in the Technical Notes Section of our website, as a ferrite suppressor. Any device used to block an RFI signal between its source and a receiver is an electromagnetic www.delevan.com. interference (EMI) shield. The measure of this ability to Continued on next page attenuate RFI is shielding effectiveness,S, which is expressed in decibels,d, the ratio of eld strength on one Actual Size side of the shield to the other side. (BF2125) One of the most versatile and cost effective shielding methods that can be used today is the API Delevan bisected ferrite cable snap assembly. The bisected styling, or familiar clamshell enclosure design offers the ultimate in adaptability. The RF absorbing material interacts directly with unwanted high frequency energy and dissipates it effectively while allowing data signals to pass unimpeded. Bisected ferrites have a concentrated, homogeneous magnetic structure with high permeability. These are consistently stable at +20C to +60C and provide RF suppression without eddy current losses. AIR GAP EFFECT The air gap in bisected ferrites actually extends current carrying capabilities with only an extremely small reduction in impedance versus solid ferrites of the same size. The gap is magnetically insignicant while it is electrically signicant as a discontinuation, thereby accommodating more current 270 Quaker Rd., East Aurora NY 14052 Phone 716-652-3600 Fax 716-652-4814 E-mail: apisales delevan com www.delevan.com 1/2009Suppressors 100 MHz 25 MHz BODY TYPE UNITS PART NUMBER API newlayouts single:APIcatalog newlayouts 8/27/10 10:02 AM Page 119 DIMENSIONS Inches 0.04 mm 1.0 IMPED- ANCE (OHMS)* BF SERIES Suppressors for Round Cables A B C D L SERIES BF - FOR ROUND CABLES in. 1.16 1.20 0.51 1.30 155 257 BF2930 A mm 29.6 30.5 13.0 33.0 in. 0.87 0.91 0.39 1.28 136 250 BF2223 A mm 22.3 23.3 10.0 32.6 in. 0.70 0.76 0.25 1.28 171 325 BF1719 A mm 17.8 19.5 6.5 32.5 in. 0.70 0.77 0.35 1.37 112 172 BF1835 B mm 18.0 19.7 9.0 35.0 in. 0.46 0.51 0.19 0.98 96 154 BF1125-5 B mm 11.7 13.0 5.0 25.0 in. 0.46 0.51 0.13 0.98 139 191 BF1125-3 B mm 11.7 13.0 3.5 25.0 in. 0.57 0.61 0.22 1.14 85 157 BF1429 C mm 14.5 15.7 5.6 29.0 in. 0.50 0.57 0.15 0.98 82 146 BF1225 C mm 12.8 14.7 4.0 25.0 in. 1.20 0.45 0.69 0.94 51 103 BF3024 D mm 30.5 11.4 17.7 24.0 in. 0.84 0.32 0.77 1.01 50 107 BF2125 D mm 21.5 8.15 19.7 25.8 in. 0.84 0.32 0.66 0.90 42 94 BF2123 D mm 21.5 8.15 16.8 23.0 in. 0.73 0.35 1.22 1.38 126 174 BF1835-9 E mm 18.6 9.0 31.0 35.2 in. 1.24 0.59 0.6 0 0.84 41 95 BF3121 D mm 31.5 15.0 15.2 21.5 Physical Parameters Material and U.L. Data API-1 Material, see characteristics and information in the Technical Notes Section. Note Impedance is typical, based on 12 turn (4.0 ) 18 AWG wire. Impedance * measurement using HP4191A. Color Black Special colors Available for bases on a non-cancellable, non returnable basis C = Cream W= White Gr = Grey U.L. Recognized All plastic and adhesive components use U.L. Recognized materials with Flammability Ratings of UL94V-0, UL-510 or UL-746C SEE Z vs. f GRAPHS ON NEXT PAGE . 270 Quaker Rd., East Aurora NY 14052 Phone 716-652-3600 Fax 716-652-4814 E-mail: apisales delevan com www.delevan.com 1/2009