VTMS. Valve Train Measurement Solution. Data sheet

Transcription

1 The measurement solution includes a GMR, an amplifier and a processing unit, which can be controlled by a PC (via USB interface). The head GLM711AVx is intended for the use with passive scales with a pitch of 1 mm. A bias magnet for the necessary magnetic field and the element is combined in a very small housing. The integration supports an optimal adjustment between and magnet which helps to generate a very high quality of signals. Together with a ferromagnetic tooth structure, the delivers two 90 degree phase shifted analog signals (sine and cosine). To allow a larger distance between measuring point and processing unit an amplifier EPV7702AAA is available. A metal housing protects the electronics. The amplification is optimized for the solution. The processing unit EPP7703AAA adapts the signals and generates an analog ratiometric output signal which is proportional to the position of the valve. The max refresh rate is 80 khz. The measuring mode is indicated by a LED. Product Overview Article Description GLM711AVA-UA Sensor head (cable length 0.5 m) GLM711AVB-UA Sensor head (cable length 1.5 m) Features Direct path or angular information of the valve position Analog output signal Level-shift for zero position Automatic determination and adjustment of parameters Controllable via PC (USB) EPV7702AAA-IA EPP7703AAA-UA Amplifier module Signal processing unit / single channel Advantages Contactless Quick Reference Guide Symbol Parameter Min. Typ. Max. Unit V CC Supply voltage V Very high temperature stability Suitable for motor-fired operation Simple signal processing I C Current consumption ma V out Output voltage range 1) V f out Output refresh rate khz Ambient temperature C 1) See figure 6 for more information. Applications Solution for valve train applications, for example: Valve lift Valve rotation Measurement setup Depiction Configuration Application Ferromagnetic toothed rack with fixed pitch; with bias magnet mounted perpendicularly to the rack Continuous position detection with analog output RoHS-Compliant Page 1 of 12

2 Electrical Data - GLM711AVx ( head) = 25 C; V CC = 3.3 V; unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Unit V CC3 Supply voltage V I C Current consumption ma R S Sensor Resistance kω V out Output voltage 1) Air gap = 0.2 mm mv f out Output frequency 1 2) - - MHz p Sensor pitch mm Ambient temperature C V Sensoff Offset voltage per V CC mv / V cc TC Voff Temperature coefficient of V off = ( ) C µv/k 1) Depends on the air gap between head and scale 2) No significant amplitude loss in this frequency range. Electrical data - EPV7702AAA (amplifier) = 25 C; V CC = 3.3 V; unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Unit V CC3 Supply voltage V I C Current consumption ma G Amplification factor f out Output frequency khz Ambient temperature C Electrical data - EPP7703AAA (processing unit) = 25 C; V CC = 3.3 V; unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Unit V CC Supply voltage V IC Current consumption ma V out Output voltage range 1) V V off Offset output voltage V Res P Resolution per pitch 2) 5-8 bit Res A Resolution over entire range bit ΔV out Output voltage change per step 1) mv / Step Res Resolution 2) with GLM711AVx µm f out Output refresh rate khz Ambient temperature C 1) See figure 6 and page 9 for more information 2) Programable feature, depends on the numbers of teeth (see table on page 9). Page 2 of 12

3 Accuracy = +25 C; unless otherwise specified. Symbol Parameter Conditions Min. Typ. Max. Unit α Absolute accuracy 1) - ± 20 - µm 1) In use with a typical tooth structure with 1 mm pitch (see figure 19 for detailed information) Mechanical Data Symbol Parameter Conditions Min. Typ. Max. Unit v Movement speed with GLM711AVx 0-40 m/s radial Working distance (scale surface ) 1) with GLM711AVx µm l ha Cable length ( head GLM711AVA) mm l hb Cable length ( head GLM711AVB) mm l a Cable length (amplifier) mm 1) See figure 17 for more information System schematics V CC3 V CC3 V CC3 PSIN PSIN APSIN NSIN NSIN ANSIN PCOS NCOS PCOS NCOS APCOS ANCOS GND GND GND Fig. 1: Functional block diagram of the head. Fig. 2: Functional block diagram of the amplifier unit. V CC3 V CC APSIN ANSIN APCOS ANCOS Position OUTPUT ANCOS Valve tooth structure Option *) *) Amplifier optional for large distance between and processing unit GND Fig. 3: Functional block diagram of the processing unit. GND Fig. 4: Total block diagram of the solution Page 3 of 12

4 Typical Performance Graphs ΔV out V out Displayed signals normalized to 1. V off pitch Fig. 5: Typical output signals of head/amplifier. Fig. 6: Output parameters of the processing unit. Valve lift [mm] Valve lift [mm] For example: Valve lift signal. Valve lift signal. Fig. 7: Typical output of processing unit. Fig. 8: Detail view of the output signal Error [µm] 0 Error [µm] Position [mm] Fig. 9: Typical absolute error. In use with 1 mm pitch Position [mm] Fig. 10: Typical error per pitch. In use with 1 mm pitch. Page 4 of 12

5 Pinning of the head GLM711 Pin Symbol Parameter 1 pcos Positive cosine output Mechanical Mechanical coding 2 ncos Negative cosine output 3 PSin Positive sine output 4 NSin Negative sine output 5 GND GND 6 V CC3 Supply voltage (3.3 V) Front view Fig. 11: Lemo connector GLM711 Side side view Dimension of the head GLM711 Active area Active area 3,60 See figure 17 for detailed adjustment and mounting information. Fig. 12: Dimension of the head. All dimensions in mm. Page 5 of 12

6 Pinning and dimensions of the amplifier module EPV7702AAA-IA Lemo Connector (output) Pad Symbol Parameter 1 V CC3 Supply voltage (3.3 V) Mechanical coding 2 GND GND 3 ansin Negative sine output apsin Positive sine output 5 ancos Negative cosine output 6 apcos Positive cosine output 3 4 Front Fig. 13: Lemo connector EPV7702AAA-IA (output) Dimension of the amplifier module Fig. 14: Dimension of the amplifier module. All dimensions in mm. Page 6 of 12

7 Description of plugs, switches and indicators of the processing unit EPP7703AAA-UA Description of the elements / BNC connector Element Description 1 LED Power on 2 On/Off Switch 3 LED Measuring mode 1 4 LED Setup active 5 Analog signal output connector (BNC) 6 Sensor/Amplifier input connector (Lemo) 2 Description of the elements / BNC connector Pad Symbol Parameter 1 V out Analog signal output 2 GND GND (shield) Fig. 15: BNC connector EPP7703AAA-UA Dimension and description of the processing unit Fig. 16: Dimension of the amplifier module. All dimensions in mm. Page 7 of 12

8 Adjustment and mounting of the -head Sensor module Sensor module Valve shaft Valve shaft Valve guide Valve guide Sensor head head Active Active area area housing Housing magnet Magnet Air gap (see fig. 19) Active sen sor ar ea Active sen sor ar ea Sensor head adjustment ok Sensor head adjustment ok * Sensor head adjustment ok, under specific conditions * Sensor head adjustment ok, under specific conditions: Depending on the valve diameter, a adjustment out of the center axis might improve the sensitivity of the. Depending on the valve diameter a adjustment out of the center axis Rule of thumb: might The improve smaller the diameter sensivity of the. Rule of thumb: The smaller the diameter the higher the deviation from the center axis. the higher the deviation from the center axis. Fig. 17: Adjustment of the head for optimal usage of the active area. Page 8 of 12

9 Functions of the processing unit EPP7703AAA-UA Communication Interface The processing unit is connected to a virtual RS-232 COM-Port of your PC. Communication with the processing unit is possible via this concept. Gain A programmable amplifier is available. It is possible to adjust the gain to suit the installation situation of the or to adapt the signal to the signal chain. Programmable Resolution The total resolution of the processing unit is 12 bit (4096). The table shows the relationship between the number of measurable tooth pitches and tooth measurement resolution per division. An increase in length measurement is therefore possible by increasing the number of the sampled teeth. The measurement resolution is reduced by this. Number of teeth Resolution (bit) Resolution 1) µm 2) µm µm µm 1) Resulting resolution with a tooth pitch of 1 mm. 2) Default setup. Level adjust The level adjust is used to remove the offset voltage (V off ) from the output signal (see Fig. 6). With the level adjust functions the zero point can be set. The zero point can be adjusted manually or automatically (default). Level shifted Over flow Fig. 18: Using the automatic mode the level is changed until no overflow occurs. Determination of the exact value of V out and ΔV out To calculate the position with the highest precision you have to determine the value of Vout manually by apply the following steps: 1. Set the output voltage to maximum output and measure the voltage V out(max) 2. Set the output voltage to minimum output and measure the voltage V out(min) 3. V out = V out(max) - V out(min), ΔV out = V out / Page 9 of 12

10 Tooth structures The modules can be used at most different toothed shapes. To get an optimal signal from the module the toothed profiles should correspond to certain relations. In the following table you will find an overview of often used toothed profiles and their relations. Recommended tooth pitches h tooth height w tooth top and width g tooth gap d air gap Pitch = p p 4 ~ p 3 ~ 2p 3 ~ p 5 Pitch = p p 4 ~ p 3 ~ 2p 3 ~ p 5 Pitch = p p 4 ~ p 3 ~ 2p 3 ~ p 5 Pitch = p p 3 ~ p 5 Fig. 19: Table with typical parameters for the design of the tooth structure. Page 10 of 12

11 General Information Product Status Article GLM711AVx-UA head Status The product is in series production. EPV7702AAA-IA amplifier module The product is in series production. EPP7703AAA-UA processing unit Note The product is in series production. The status of the product may have changed since this data sheet was published. The latest information is available on the internet at Disclaimer Sensitec GmbH reserves the right to make changes, without notice, in the products, including software, described or contained herein in order to improve design and/or performance. Information in this document is believed to be accurate and reliable. However, Sensitec GmbH does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. Sensitec GmbH takes no responsibility for the content in this document if provided by an information source outside of Sensitec products. In no event shall Sensitec GmbH be liable for any indirect, incidental, punitive, special or consequential damages (including but not limited to lost profits, lost savings, business interruption, costs related to the removal or replacement of any products or rework charges) irrespective the legal base the claims are based on, including but not limited to tort (including negligence), warranty, breach of contract, equity or any other legal theory. Notwithstanding any damages that customer might incur for any reason whatsoever, Sensitec product aggregate and cumulative liability towards customer for the products described herein shall be limited in accordance with the General Terms and Conditions of Sale of Sensitec GmbH. Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. Unless otherwise agreed upon in an individual agreement Sensitec products sold are subject to the General Terms and Conditions of Sales as published at Page 11 of 12

12 General Information Application Information Applications that are described herein for any of these products are for illustrative purposes only. Sensitec GmbH makes no representation or warranty whether expressed or implied that such applications will be suitable for the specified use without further testing or modification. Customers are responsible for the design and operation of their applications and products using Sensitec products, and Sensitec GmbH accepts no liability for any assistance with applications or customer product design. It is customer s sole responsibility to determine whether the Sensitec product is suitable and fit for the customer s applications and products planned, as well as for the planned application and use of customer s third party customer(s). Customers should provide appropriate design and operating safeguards to minimize the risks associated with their applications and products. Sensitec GmbH does not accept any liability related to any default, damage, costs or problem which is based on any weakness or default in the customer s applications or products, or the application or use by customer s third party customer(s). Customer is responsible for doing all necessary testing for the customer s applications and products using Sensitec products in order to avoid a default of the applications and the products or of the application or use by customer s third party customer(s). Sensitec does not accept any liability in this respect. Life Critical Applications These products are not qualified for use in life support appliances, aeronautical applications or devices or systems where malfunction of these products can reasonably be expected to result in personal injury. Copyright 2016 by Sensitec GmbH, Germany All rights reserved. No part of this document may be copied or reproduced in any form or by any means without the prior written agreement of the copyright owner. The information in this document is subject to change without notice. Please observe that typical values cannot be guaranteed. Sensitec GmbH does not assume any liability for any consequence of its use. Sensitec GmbH Georg-Ohm-Str Lahnau Germany Tel Fax sensitec@sensitec.com Page 12 of 12