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PECIFICATIONS

InputDifferential buffered sinusoidsUse with encoder modelVL18 linear; Vx20, Vx35 rotaryMax code length on disc or scale15 bits (32,768 cycles). See encoder data sheet.Interpolated resolution5 bits (32 steps per optical cycle)Max final resolution20 bits (1,048,576 steps)Absolute outputNatural binary byte-wide multiplexedMax input frequency200 kHz disc/scale data rateMax update rate (see note 1)At least 1 MHz, user dependent. See timing diagram.Auxiliary output (see note 2)Quadrature square waves plus index at disc/scale resolutionMax input cable length (see note 3)50 ft (15 m) Operating temperature range Standard (commercial) Optional (automotive)0°C to 70°C -40°C to +85°CWeight, oz (g) PKG = 0 (board only) PKG = 1 (board + mounting plate) PKG = 2 (fully enclosed0.9 (26)2.1 (60)3.1 (88) Notes: 1. At maximum speed, the Encoder + VB Virtual Absolute system may have an LSB rate up to 6.4 MHz. Due to dynamic effects, the lowest 2 or 3 bits may not be accurate. However, accuracy returns as the encoder slows down again, and no "counts" are lost because a encoder is not an incremental encoder. See the Model VB Interpolating Decoder User's Manual for a more thorough explanation of effective resolution versus speed - Gurley's "automatic transmission" for high resolution encoders.2. This output is not for determining position and is not guaranteed to change synchronously with the absolute output. It is provided to simplify closing the velocity loop as required by some servo systems. Quarter-cycle gated index is active only after encoder initialization.3. Recommended maximum includes +5V power and assumes proper grounding, industrial shielding, and cable routing. Longer runs are possible, depending on the EMI environment. Encoder-to-decoder cable runs over 99 inches require signal extension cables, ordered separately.
As part of our continuing product improvement program, these specifications are subject to change without notce.

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Gurley Precision Instruments514 Fulton StreetTroy, NY 12180 U.S.A.(800) 759-1844, (518) 272-6300, fax (518) 274-0336, Online at www.gurley.com, e-mail: info@encoders.com V3.1

GPIGPI

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