DS Absolute position, rotary Electric Encoder

Transcription

1 DS , NOV DS-7-16 bsolute position, rotary Electric Encoder The DS-7 is a member of the DS series of Electric Encoders, based on Netzer Precision proprietary technology. The Electric Encoder offers many advantages - some unparalleled Low profile (8 mm). Hollow, floating shaft. No bearings or other contacting elements. High resolution and precision. High tolerance to temperature extremes, shock, moisture, EMI, RFI and Magnetic fields. Very low weight. Holistic signal generation nalog or Digital interfaces. Mechanical llowable mounting eccentricity ±0.1 mm llowable rotor axial motion ±0.1 mm Rotor inertia gr mm 2 Total weight 10 gr Outer Ø /Inner Ø/ Height 7 / 10 / 8 mm Material (stator, rotor) Ultem polymer The Electric Encoder is unique in being holistic, i.e., its output reading is the averaged outcome of the whole area of the rotor, This feature makes the Electric Encoder forgiving to mounting tolerances, mechanical wander etc. The absence of components such as ball bearings, flexible couplers, glass disc, light sources and detectors, along with very low power consumption makes the Electric Encoder virtually failure free. The internally shielded, DC operated Electric Encoder includes an electric field generator, a field receiver, a sinusoidal shaped dielectric rotor, and processing electronics. The output signals of Electric Encoder are analog Sine / Cosine representing the rotation angle. The digital outputs are obtained by further processing - which may be either internal or external to the encoder. The combination of precision, low profile, low weight and high reliability have made Netzer Precision encoders particularly suitable to a wide variety of critical applications including, but not limited to medical equipment and aerospace. Electrical Supply voltage 5V ± 5% Interconnection Shielded cable or Cable Length 1,500 mm MX Environmental EMC IEC , IEC Operating temperature range Digital: -40 C to 85 C Relative humidity 98% Non condensing Shock endurance 100 g for 11 ms Vibration endurance 20 g Hz Protection IP 40 Characteristics ngular resolution Static error Maximum operational speed Measurement range Power On - Max. operational speed uild In Test IT 17 bits ; 11,072 CPR < 25 mdeg 1,500 rpm Unlimited rotation. RPM, <=20 /sec Optional 1

2 DS-7-16 bsolute position, rotary Electric Encoder DS , NOV Digital SSi Interface Synchronous Serial Interface (SSI) is a point to point serial interface standard between a master (e.g. controller) and a slave (e.g. sensor) for digital data transmission. SSi / iss Output signal parameters Signal latency ~250 μsec Output code inary Serial output Differential RS-422 Clock Differential RS-422 Clock Frequency MHz Position update rate (Max) 0 KHz Current consumption 180 m Digital iss-c Interface iss C Interface is unidirectional serial synchronous protocol for digital data transmission where the Encoder acts as slave transmits data according to Master clock. The iss protocol is designed in mode and C mode (continuous mode).the iss-c interface as the SSi is based on RS-422 standards. Monoflop time SSi 25 μsec Description Recommendations n Total number of data bits T Clock period f= 1/T Clock frequency MHz Tu it update time 200 nsec Tp Pause time 26 - μsec Tm Monoflop time >25 μsec Tr Time between 2 adjacent requests Tr > n*t26 μsec fr=1/tr Data request frequency Electric Encoder CLK / NCP RX [] CLK / NCP RX [] (gray) (blue) DT / NCP TX [] (yellow) DT / NCP TX [] (green) Gnd (black) 120 Ω Host System 5V 5V SSi / iss interface wires color code Clock Grey Clock - lue Clock Data - Yellow Data Green Data GND lack Ground 5V Red Power supply Software tools: (SSi / iss - C) dvanced calibration and monitoring options are available by using the factory supplied Electric Encoder Explorer software, This facilitates proper mechanical mounting, offsets calibration and advanced signal monitoring. bit # Description Default Length 27 ck 26 Start Period during which the encoder calculates the absolute position, one clock cycle Encoder signal for start data transmit 0 1/clock 1 1 bit 25 0 start bit follower 0 1 bit P bsolute Position encoder data 7 Error Error (amplitude levels) 1 1 bit 6 Warn. Warning (non active) 1 1 bit CRC Timeout The CRC polynomial for position, error and warning data is: x 6 x 1 x 0. It is transmitted MS first and inverted. The start bit and 0 bit are omitted from the CRC calculation. Elapse between the sequential start request cycle s. 6 bits 25 μs 5V (red) 2

3 DS , NOV DS-7-16 bsolute position, rotary Electric Encoder nalog Interface Coarse and Fine channels The DS-7 has two operational modes: a Coarse-mode and a Fine-mode - equivalent to two separate encoders in a common housing. The modes are selectable by a logic C/F command; logic 0 (0V to 0.5V) selects the Coarsemode, which has Electrical Cycle/Revolution (EC/R) while logic 1 (V to 5V) selects the Fine-mode which has 16 EC/R. The switching time is less than 1 ms. The Coarse-mode outputs need to be read only upon system initiation after which the encoder is permanently switched to the Fine mode. Coarse and Fine sine / cosine pairs are used to calculate the initial absolute position, from that point tracking the Fine-channel outputs provides the absolute mechanical rotation angle with the specified accuracy and resolution. ll output signals are referenced to an internally generated voltage Vr (~2.25V) R Electric Encoder 4.5V SINE (FINE) SINE (CORSE) COSINE (FINE) R COSINE (CORSE) LP filter 5V C/F Gnd Sin Vr (~2.2V) LP filter Cos (Red) (Grey) (lack) (lue) (Green) (Yellow) Vref/2 Vref/2 Host System nalog interface 1 GND lack Ground 2 C/F Grey Coarse / Fine Sine lue Sine signal 4 Vr Green V referencecosine signal 5 Cosine Yellow Cosine signal 6 5V Red P.S. 4.7K 10nF 4.7K 10nF Vref Sample Sine /D Vref Cosine /D Output signal parameters Electric Cycles (Fine / Coarse channels) 16 / Signal latency 250 μsec Fine-mode output noise (DC to 1kHz) 100 µv (p-p) Fine-mode output amplitude ±400mV ± 20% Coarse-mode output amplitude ±00mV ± 20% Phase relationship (CW shaft rotation - seen from top) Sine leads Cosine Signal bandwidth DC to 1 khz Current consumption 10m bsolute Position calculation: The analog Sine / Cosine outputs convey the Electrical angle of the Coarse or Fine signals. The bsolute mechanical angle is computed by digitizing the analog signals.

4 DS , NOV DS-7-16 bsolute position, rotary Electric Encoder DS D F - S 0 - n n n DS Product line Outer Diameter Fine ECR Outputs: D - Digital : SSi E - Digital : iss-c 0 - nalog 1 Vp-p nnn - Custom C - Connector (optional) 0 - Flying leads (default) Interconnection: S - shielded cable 250 mm (default) C - Encapsulated external module Resolution Code it CPR F 17 11,072 IT (uild In Test): optional [ ] - none - IT Netzer Cat No.: C Provider: Ray-Q US. wire CT No: RQ21210 Cable: 0 WG twisted pair () :2 (0 WG 25/44 finned copper, 0.15 PFE to Ø0.6 ± 0.05 OD). Temperature rating: -60 to 150 Deg C. raided shield: Thinned copper braided 95% min. coverage. Jacket: 0.45 silicon rubber jacket Ø.45 ±0.2 OD WG single insulated wire.45 ± 0.20mm Pair # 1 2 Color Red / lack Gray / lue Green / Yellow 0 WG twisted pairs () raided shield Jacket 0.45mm Related documents: DS-7 User Manual : Mechanical, Electrical and calibration setup. Demonstration Kit: DS-7DKIT-01: Includes,mounted encoder on rotary jig, and RS-422 to US converter. Ø 0.61 ± 0.051mm 4

5 DS , NOV DS-7-16 bsolute position, rotary Electric Encoder C C 1 1 D D ENCODER TOP VIEW SLOTS FOR ENCODER CLMP EQ.SP ENCODER OTTOM VIEW E SECTION - SCLE 2 : 1 The information contaned in this drawing is the sole property ot Netzer Precision Motion Sensores Ltd. ny reproduction in part or whole without the written permission of Netzer Precision Motion Sensors Ltd.is prohibited. The drawing is confidential,and is the property of Netzer Precision Ltd. it must not be disclosed to a third party without written consent of Netzer Precision Ltd. NME SIGNTURE DTE F DRWN VDIM.D CHK'D PPV'D JCO N UNLESS OTHERWISE SPECIFIED: TITLE: DS-7 ICD SURFCE FINISH: N6 DIMENSIONS RE IN mm MTERIL: Coating: LINER TOLERNCES: 0.1 mm DWG NO. : Revision : NGULR TOLERNCES: 0.5 deg LL CHMFER: 0.1 mm X 45 CT NO. : 01 DS-7 ICD-01 SCLE: 1:1 SHEET 1 OF 1 5

6 DS-7-16 bsolute position, rotary Electric Encoder DS , NOV C C 4 M4 10mm 12 max 2 9 SECTION E-E 2 SECTION - 1 HOLES M2 EQ.SP min REF Shaft - End installation (step) No Part Description QTY. 1 DS-7-16 Included DS-7 encoder 1 2 EPK005 Included Kit Kit, x M2 Encoder clamps ST. ST. 1 Shaft End installation Washer DIN M-DS7-004 Optional kit Critical dimensions marked with * 4 Screw DIN 7984 M4x6. 1 6

7 DS-7-16 bsolute position, rotary Electric Encoder DS , NOV SC2SSi, DS-7 external digital module (SSi/iSS) Part Description QTY. SC2SSi-0 Included with DS-7 CT No. 1 7