MU-MA Rotary Wafer Switch General Specifications: These versatile miniature switches have 25.4mm 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. Maximum Working Voltage: 300 Vdc / ac (rms) Insulation Resistance: Not less than 500 megohms Contact Rating - Current Carrying: 2 amp at 500 Vdc continuous (between any 2 parts requiring electrical insulation) Current Breaking with a Resistive / Non-reactive Contact Resistance (initial): 10 milliohms maximum load: 150mA at 250 Vac (rms) at 100 mV (rms). 100mA max Proof Voltage: 1000 Vrms at sea level Mechanical End Stop Strength: 0.8 0.1Nm (114oz Ins) Maximum Switching Per Wafer No of Poles 36 MU-MA 30 MU-MA 45 MU-MA 60 MU-MA 15 MU-MG 1 Pole 2 to 10 ways 2 to 12 ways 2 to 8 ways 2 to 6 ways 2 wafers (fixed stop at positions (providing 1 pole 24 3, 5 & 7 ways) way switching) 2 Pole 2 to 5 ways 2 to 7 ways 2 to 6 ways 3 Pole 2 to 4 ways 2 to 5 ways 2 or 3 ways 4 Pole 2 or 3 ways 2 to 4 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 - Index Mechanism: The type MU mechanism provides indexing angles of 30, 36, 45 and 60 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 18 x 10- Nm (10 to 26 oz Ins) Medium 14 to 32 x 10- Nm (20 to 46 oz Ins) High 28 to 56 x 10- 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. Contacts: Standard - Silver plated brass Alternatives - Hard gold plated or silver contacts are available at extra cost as are contacts with gold flash Terminations: Forward, standard: Straight, alternative Rotor Blades: Standard - Shorting (make before break MBB) Alternative - Non-shorting (break before make BBM) Insulation: Stator - Moulded glass fibre loaded Diallyl Phthalate (DAP) Rotor - Polycarbonate Finish: Index springs stainless steel, other metal parts passivated zinc plated. Finishes to order. Mounting Details: Imperial (standard) Metric (alternative) Bush 3/8 x 32 TPI (Whit) M10 x 0.75 Shaft 0.25 dia 6 mm dia Nut 0.525 A/F 14 mm A/F The alternative is optional in each case. Unless otherwise specified, each switch is supplied with a lock washer. Caution: Our range of rotary wafer switches use polycarbonate rotors, the rotor blade/moving contact is secured to the rotor using a staking process to deform moulded locating pips. Please be aware that the use of some solvents and excessive heat as may be present from a heat gun could cause the following issues and should be avoided. In the case of solvent abuse the retaining pips may become brittle and break off resulting in the blades becoming detached and similarly the application of heat >140C can cause the deformed moulding to reassert itself again causing failure of the blade retention. Please Note: In line with continued development we reserve the right to amend specification without prior notice (Rev1 08/14) NSF Controls Ltd l Ingrow Bridge Works l Keighley l West Yorkshire l BD21 5EF l UK l Registered in England No. 3378269 T: +44 (0) 1535 661 144 l F: +44 (0) 1535 661 474 l E: info nsfcontrols.co.uk l www.nsfcontrols.co.uk MU-MA Rotary Wafer Switch Dimensions Are In Millimetres Key To Details A Shaft Length: Optional 0.40 (0.016) / (25mm if not specified) B Bushing Thread Length: Preferred standard 9.5 (0.375), 6.35 (0.250) available as an alternative Special lengths if necessary C Flat Length: Length to specification tolerance 0.40 (0.016) Special shaft terminations may be provided to special requirements D Angle of Flat: To specification 2 specify position of flat, with switch shaft in fully anti-clockwise position when viewed from front or knob end E Flat Thickness: Standard 5.55 0.15 for grub screws 4.95 0.05 for push-on knobs F Distance of Locating Lug From Shaft: Measured centre line to centre line 9.5mm standard G Angle of Locating Lug: Type MU mechanism 45, 135, 225 and 315 from horizontal centre line The alternative A type mechanism also includes 0 and 180 as viewed H Bushing Shoulder: Standard 3.2 (0.125) J Front Spacer: Minimum dimension MU-MA 9.5 (0.375), A-MA 5 K Other Spacers: Minimum dimensions With clips facing same direction NIL With clips facing away or flat clips NIL With clips facing each other 3 L Spacer Length: If no spacer 2.4 any length spacer required may be inserted at this point M Thread Extension: Typically 3 x M2 x 0.4 any length required P Standard Locating Lug Lengths: Unsealed, projects 1.6 beyond mounting face sealed 0.05/0.15 below mounting face. Please Note: In line with continued development we reserve the right to amend specification without prior notice (Rev1 08/14) NSF Controls Ltd l Ingrow Bridge Works l Keighley l West Yorkshire l BD21 5EF l UK l Registered in England No. 3378269 T: +44 (0) 1535 661 144 l F: +44 (0) 1535 661 474 l E: info nsfcontrols.co.uk l www.nsfcontrols.co.uk