Gurley Model 7700 Virtual AbsoluteEncoder
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Gurley Model 7700 Ò Virtual Absolute Encoder Motion Type: Rotary & *Linear Usage Grade: Military, Industrial Output: Virtual Absolute w/external decoding electronics Absolute output Many disc sizes Friction-free operation Low-cost solution The model 7700 Incremental and Virtual Absolute encoder is a compact, non-contact modular encoder with superior performance. Available in many resolutions and configurations, it is easy to install and its optional commutation tracks eliminate hall effect sensors for brushless motors. Features common to both models include: · -40C to +100C operating temperature · Low power consumption · Single phased-array optoelectronic ASIC · LED illumination for long service life (>100,000 hours) Incremental systems (7700 encoder + disc/hub) include: · Resolutions up to 5000 cycles/rev (20,000 counts/rev, or 0.018degrees/count) · TTL/CMOS-compatible square wave output, 10mA sink · Standard once-per-rev zero index signal · Optional three-phase 2, 4, 6, or 8 pole pair motor commutation Virtual Absolute systems (7700 encoder + disc/hub + VG, VH or VJ decoder) include: · Resolutions from 12 bits (4,096 steps) to 24 bits (16,777,216 steps) per turn · True absolute position after a small initialization, depending on disc diameter - see disc library table for initialization angles · Compact decoder circuits provide byte-wide parallel (VG), USB (VH), or SSI serial (VJ) outputs. Please refer to individual decoder datasheets for more information · Built-in patented pseudorandom and quadrature error detection for high reliability * Consult factory for information on linear encoder option Gurley Precision Instruments 514 Fulton Street Troy, NY 12180 U.S.A. (800) 759-1844, (518) 272-6300, fax (518) 274-0336, Online at www.gurley.com, e-mail: info@gurley.com

SPECIFICATIONS ELECTRICAL Input power Light source Infra-red LED; rated for long service life >100,000 hours Output Signals TTL-compatible square waves or micro-current sine waves MECHANICAL Materials Encoder body Disc Hub Molded Ryton PPS Vacuum-deposited chrome pattern on glass Aluminum (stainless steel optional) Weight Read head PERFORMANCE Frequency response Incremental: 125 kHz, all channels; VA: 2 kHz disc rate ENVIRONMENTAL Operating temperature Storage temperature Commutation Tracks (Incremental Encoder options only) If your motor has P poles, you need a disc with N cycles/rev...

SPECIFICATIONS Built-in Error Detection (Virtual Absolute options only) With the addition of a patented Gurley Virtual Absolute pseudorandom tag decoder, the encoding system continuously monitors signal integrity in two important ways to improve system reliability. The first way is actually a well-known test that can be applied to any incremental encoder, where the timing track signals from the encoder are inspected for disallowed quadrature sequence. If a quadrature sequence fault is detected, the tag decoder will immediately be reset into Wait mode, the status bit will be set to a logic...

7700 Disc Library VA Initialization Angle (degrees) Disc Line Count 7700 Virtual Absolute binary discs are in red bold italics Need a disc diameter not called out in our library? GPI can manufacture disc diameters ranging from 1.30” through 8.00”. In many cases, a binary (2n) resolution is achievable at or near the diameter you need. If a particular diameter is more important than having a binary number of counts/rev, the count can be adjusted to realize the desired diameter. Or other resolutions like 36,000 counts/rev are possible at different diameters. Gurley Precision Instruments 514...

7700 READHEAD DIMENSIONS Module Outline Dimensions Module Interface Module 0130 M - Mounting dimension . . .0.986 in H - Hub maximum O.D. . . . . 1.07 in DISC MOUNTING same for rotary disc or linear scale Disc Material Glass 0.04” [1 mm] thick (standard) Gurley Precision Instruments 514 Fulton Street Troy, NY 12180 U.S.A. (800) 759-1844, (518) 272-6300, fax (518) 274-0336, Online at www.gurley.com, e-mail: info@gurley.com

7700 READHEAD & DISC DIMENSIONS Side Pin Layout Output Format The Optical Encoder Module with side exit pins comes standard with A, B and Z (Index) channels. OUTPUT STAGE Channel A Channel B Index Z A leads B, cw Top Pin Layouts The Optical Encoder Module with top exit pins comes standard with A, B, and Index channels. Commutation channels are optional. Module 175 Disc and Hub D - Disc O.D. . . . . . . 1.75 in. H - Hub O.D. . . . . . . 1.00 in. Shaft Size Set Screw 2-56* *#035 wrench to tighten. Module 130 Disc and Hub D - Disc O.D. . . . . . .1.30 in. H - Hub O.D. . . . . . . 0.61 in....

7700 VIRTUAL ABSOLUTE CONFIGURATIONS 7700 with VG Multiplexed decoding electronics ribbon cable, standard 0.050 pitch 7700 with VH USB decoding electronics ribbon cable, standard 0.025 pitch 7700 with VJ SSI decoding electronics 7700 with VK SSI dual input decoding electronics Reading two separate readheads & disc/hub assemblies into one VK decoder. Good for Az & El gimbal applications Reading two readheads on one common disc/hub assembly into one VK decoder. Good for applications where high accuracy is required. Gurley Precision Instruments 514 Fulton Street Troy, NY 12180 U.S.A. (800)...

ORDERING INFORMATION Module OUTPUT A analog micro-currents for VH & VJ decoders B analog buffered differential for VK decoder C TTL with commutation D TTL with internal doubler circuit T TTL-compatible square waves CONNECTOR T Top pins S Side pins V Mates with VG decoder U Mates with VH or VJ decoders M Mates with VK decoder DIAMETER 0130 1.30” disc 0175 1.75” disc RESOLUTION 5-digit resolution code; see page 4 TYPE R Rotary; consult factory for Linear SPECIAL FEATURES N No Special Features CABLE 00 for Top or Side pins 12 for V, U, M decoders (standard in inches) MATL COMM LINES 5-digit...