ENGINEERING BULLETIN June 1971 NSF ROTARY WAFER SWITCHES Models JKM and JKB Bulletin No. 6 ~. S TPs NNEC LEAN oY ( Key XB OAT SBrnurkNSF ENGINEERING BULLETIN Continued from overleaf INSULATION. Stators and Rotors: Highest grades of punching quality S.R.B.P. materials to B.S. 2076 Grade L. Tropical grade material to B.S. 2076 grade H is available at extra cost, if desired. i 4 FINISH. C; Standard: All ferrous parts plated ; non-ferrous parts clean. ; . Special : Special finishes to withstand tropical conditions are available when specified. MOUNTING DETAILS. Unless otherwise specified, each switch is supplied with one fixing nut @ thick, .525 across flats, threaded 3 x 32 T.P.L. Whitworth form and one 3 internal tooth steel lock-washer. Various methods of mounting may be provided to meet customers special requirements. Panel and spindle sealing is available if required. CONSTRUCTION. The switch sections are spaced by tubular metal spacers and held in place with a positive relationship to the index mechanism assembly by side strut screws. STANDARD CONTACT ARRANGEMENTS. Please refer to Engineering Bullezin No. 7 for details of standard contact arrangements and use these whenever possible. MAIN SWITCHES JKM only. Switches, rated at | amp., 250 volt, A.C. or D.C., are available in SPST, DPST, SPDT, or 3 - way (making 3 contacts when thrown). A.C. switches are attached to end of shaft and may be arranged to operate at any given position through the rotation of the switch. Qal) I (29-4) -2495" pia. (64) 3475" / if avel | iI . | | 308) | 3x32 TRIWHITTHREAD | 3 be | ff to-5) rey aL KIL DIA. e-Ba FIGURES WITHIN BRACKETS ARE APPROX. METRIC EQUIVALENTS KEY TO DIMENSIONAL DIAGRAM. A. Shaft length: Optional 42%. Diameter : .2475 J-K-L. Spacers : 7% min. with lugs facing each other; .2495 (after plating). 2 min. with lugs facing same direction as adjoining sections ; yy min. with lugs facing away from each other. No max. limit (within switch limita- tions.) B. Bushing Thread length : Standard or 3. Special lengths if necessary. Threads 3 Xx 32 T.P.. Whitworth form. C. Flat length : Standard not more than 3%, in no case If no spacer, 5 min. any lengeh spacer desired may closer than 74 to end of bushing. Tolerance be inserted at this point ; 5 Standard. = cay". Special shaf inati b vided : s&h pecial shaft terminations may be provide N. Thread extension : 1 ; to meet customers particular requirements. P Specif: : n: 3 6BA., any length desired. D. Angle of flat: as desired =2. Specify position of , pecify maximum overall length, if important. switch in which flat is shownfully counter clock- Q. Shaft extension at rear: nominal 4 to 2Dimen- setien ie meninwwnd tinne infene mineines dia STATOEVIVAOEY 6 wanmee flowWAS NN DENING Engineering Bulletin No.29 . oO ; : NS vere Rotary Wafer switch - model MU-MK. General Information These switches have 32mm (1.26) diameter moulded wafers with 22 contact positions providing up to 12 switching positions. The stators are moulded from glass fibre loaded diallylphthalate. Optional features include concentric shafts, panel and spindle seals and rigid terminations for printed circuit connections. Characteristics. Electrical, Maximum working voltage 300Vac/de. Contact rating, Current carrying Samp continuous. Current breaking with a resistive/non-reactive load. 60mA at 250Vdc. 150mA at 250Vac (rms). 500mA at 30Vac/de (rms). Proof Voltage. 1000Vrms at sea level. Insulation resistance. Not less than 2 Gohms. (between any 2 parts requiring electrical insulation) Contact resistance (initial). 10 milliohms maximum. 100mA. max. Maximum Switching. No. of Poles. 30 MU-MK 1 Pole. 2 to 12 ways 5 Pole. 2 to 3 ways 2 Pole. 2 to 9 ways 6 Pole. 2 ways 3 Pole. 2 to 5 ways 7 Pole. 2 ways 4 Pole. 2 to 4 ways Standard Contact Arrangements. Please refer to Engineering Bulletins RW25a for details of standard contact arrangements and use these whenever possible. Index Mechanism. The preferred mechanism used with the MK wafers is the Type MU providing indexing angles of 30, 45 and 60, (see Bulletin RW36 for full technical details). Torque ranges available are:- Tioht Tin ld 102Nm (10 to 20 a7 ins} Medinm 14 ta 2% x 10-2 Nm (20 to 40 07, ins.)Engineering Bulletin No.29 Rotary Wafer switch - model MU-MK. Model MU-MK. rote OrvANAW NAKA wee $d General Information Characteristics. Electrical, Maximum working voltage, Maximum Switching. Standard Contact Arrangements. Index Mechanism. Contacts & Terminations. Rotor Blades. Insulation. Finish. Mounting Details. Construction. NSF Controls Limited Keighley West Yorkshire BD21 SEF AR YEE Engineering Bulletin No.25 Rotary Wafer switch - model MU-MA. These versatile miniature switches have 25.4 mm diameter moulded wafers and are available in 2 versions, 36 indexing - having 18 clip positions and 30 indexing - having 22 such positions. 15, 45 and 60 indexing are variations of the latter. Optional features include concentric shafts, panel and spindle seals, printed circuit terminations and momentary contact models. 300Vde/ac (rms). Contact rating, Current carrying 2amp continuous. Current breaking with a resistive/non-reactive load. 50mA at 300Vdc/ac (rms). 00mA at 30Vde/ac (rms). Proof Voltage. 1000Vrms at sea level. Insulation resistance. Not less than 500 megohms at 500Vdc. (between any 2 parts requiring electrical insulation) Contact resistance (initial). 10 milliohms maximum at 100mV (mms). 100mA.max. Mechanical. End stop strength. 0,8 4 0,1 Nm (1140z.in.) Temperature range. 40C. to +100C. No. of Poles. 36 MU-MA (b) | 30MU-MA(a) | 45MU-MA (c) | 60 MU-MA (d) 15 MU-MG 10 Positions. 12 Positions. 2 waters 1 Pole. 2 to 10 ways 2 to 12 ways 2 to 8 ways 2 to 6 ways providing 1 pole 2 Pole. 2 to 5 ways 2 to 7 ways (fixed stop at 2 to 6 ways 24 way 3 Pole. 2 to 4 ways 2 to 5 ways positions 3, 5, 2 or 3 ways switching. 4 Pole. 2 or 3 ways 2 to 4 ways and 7 ways) 2 or 3 ways 5 Pole. - 2 to 3 ways 2 ways only 6 Pole. - 2 ways only on-off 7 Pole. - 2 ways only - Please refer to Engineering Bulletins RW25a (30 and 45) or RW25b (36) for details of standard contact arrangements and use these whenever possible. The Type MU mechanism provides indexing angles of 30, 36, 45 and 60, (see Bulletin RW36 for full technical details). The low friction moulded cam followers in the assembly ensures a smooth indexing action. Balance pressure springs provide consistent and readily reproducible total switch torque values within the following ranges. Light 7 to 18x 10-7 Nm (10 to 26 oz, ins,) Medium 14 to 32 x 10-? Nm (20 to 46 oz, ins,) High 28 to 56 x 10-7 Nm (40 to 80 oz, ins,) Type A indexing mechanism may also be used as an alternative where a simpler, space saving mechanism is required. The switch then becomes model A-MA. 30 indexing only. Standard. - Silver plated brass. Alternatives. - Hard gold plated or silver contacts are available at extra cost as are contacts with gold flash. Termination s. - Forward, standard: Straight, alternative. Standard . - Shorting. (make before break. MBB.) Alternative. - Non-shorting. (break before make. BBM.) Stator. - Moulded glass fibre loaded diallylphthalate (DAP) Rotor. - Polycarbonate. Index Springs, Stainless steel: other metal parts, passivated zinc plated. Finishes to order. Imperial (standard). Metric (alternative) Bush 3/8 x 32TPI (Whit.) M10 x 0.75. Shaft 0.25 dia. 6mm, dia. Nut 0.525 A/F. 14mm A/F. The alternative is optional in each case. Unless otherwise specified, each switch is supplied with an internal tooth steel lock washer. The switch wafers are spaced by tubular metal spacers and held in place, with a positive relationship to the index mechanism, by side strut screws. $+44(0) 1535 661144 Fax: +44(0) 1535 661474 Email: mail@nsfcontrols.co.ukEngineering Bulletin No.34 Rotary Wafer Switch Type MSD. General Information The MSD is essentially a Heavy Duty rotary switch which is rated at Gamps. at 250Vac. Designed to handle higher currents than is possible with normal types of leaf clip wafer switches. It is eminently suitable for use in a wide variety of electronic and domestic equipment. Developed by NSF technical service to incorporate modem materials and techniques which give the wena a a TD ne enti. . Rotary Wafer switch - model MU-MA. Variations. 1. Biased indexing is available giving momentary contact on positions 8 to 7, 5 to 4, 4 to 3,3 to2 and2tolaswell afat a Linn-ndT 4. nnntenO ON 935dS riwe EClLsY N ads ON LYVd , Aor 3A0- Sel ssWOLsSAD BP S3LVO +03x93H9 Jp, +03S1Va a SAONVHI 3ONVHO ON HO lanssi 119 SN k ut gat af x 20h te agg (Ny Litto Ni BAe SNT dds) worl ON LUVd AVIS} WIDUOI/EOSIO4 WO! SNILYOHS = Saas Me 4 & ee SNOrLIsod 40 os ! $NOI193S 30 SALON OV3NHL LIHA ['d'L CE X 48/8 ee I ACT a4 Zl sy a OE 35 " $itth isons | Tasha pas | HOLIMS XWe/Z! WSGOW *4"S"N z fr mane permanant DS2 os meee ees Engineering Bulletin No.34 , Rotary Wafer Switch Type MSD. e The switch wafers are spaced by tubular metal spacers and held in place, with a positive relationship to the index mechanism assembly, by side strut screws. Construction. Maximum roller bearing plote displacement when cperating 30 17.5mm 60 22.3mm. IL ; - ~ eed m |" 4 at . T N, pT : Ne KO q First wafer \ assembly. REAR VIEW OF SWITCH WITH EITHER TYPE OF INDEXING MECHANISM