SCHMIDT Flow Sensor SS Instructions for Use

Transcription

1 SCHMIDT Flow Sensor SS Instructions for Use

2 SCHMIDT Flow Sensor SS Table of Contents 1 Important Information Safety instructions Use of oxygen (O 2 ) Information concerning the proper use of O Information concerning a safe installation Application range Determination of the place of installation Mounting instructions Electrical connections Startup LED display Table showing the signaling options Description of error signaling Service information Technical Specification Declaration of conformity Imprint: Copyright 2008 SCHMIDT Technology All rights reserved. Printed in the Federal Republic of Germany Version: B Instructions for Use SS Page 2/16

3 1 Important Information These instructions for use must be read completely and observed carefully, before putting the unit into operation. Any claims under the manufacturer's liability for damage resulting from non-observance or non-compliance with these instructions will become void. Tampering with the device in any way whatsoever - with the exception of the designated use and the operations described in these instructions for use - will forfeit any warranty and exclude any liability. The unit is designed exclusively for the use described below (see chapter 3 Application range). In particular, it is not designed for direct or indirect personal protection. SCHMIDT Technology cannot give any warranty as to its suitability for a certain purpose and cannot be held liable for errors contained in these instructions for use or for accidental or sequential damage in connection with the delivery, performance or use of this unit. 2 Safety instructions 2.1 Use of oxygen (O 2 ) RISK of FIRE and EXPLOSION! The improper use of gas mixtures having an oxygen percentage of at least 21% or pure oxygen can cause fire or explosion. Due to a careful cleaning during production and packaging of the sensor and its accessories according to the standard IEC/TR 60877:1999, the sensor can be used in gas mixtures with an oxygen percentage of at least 21 % or in pure oxygen. Instructions for Use SS Page 3/16

4 This standard may be restricted by: - The operating specification of the SS with regard to temperature and pressure. - Special conditions regarding the use of biatomic oxygen (O 2 ). Important information It is explicitly pointed out that the customer, when opening the packaging, assumes full responsibility for the cleanliness of the sensor and its accessories according to the standard IEC/TR 60877: Information concerning the proper use of O 2 The general rule applies that a soiling of sensor parts that come into contact with oxygen must be absolutely avoided. - The installation site must be carefully cleaned before mounting the sensor. - Make sure to use only clean tools and material for the installation. - Before opening the packaging film, remove dirt such as dust from the film, if necessary. - If possible, open the packaging film and take out the sensor directly at the installation site. - Otherwise open the packaging film at an appropriate and clean workplace and store the sensor in an appropriate, cleaned and dust and humidity tight container. - Do not touch the oxygen contacting sensor parts with bare hands. - Use clean and non-fluffy gloves or cloths or similar to handle the sensor. Instructions for Use SS Page 4/16

5 2.3 Information concerning a safe installation When mounting and dismounting the sensor, it is absolutely necessary to observe the instructions mentioned below: 1. The sensor may only be mounted and dismounted when no pressure is applied. 2. The spigot nut (AF24) of the screw pipe connection must be firmly tightened before applying compressed air. Permitted tightening torque: Nm 3. In case of mechanical strain (vibration), the nut must be secured additionally (e.g. using a commercially available screw lock glue). 4. Make sure to close the safety chain before pressure is applied. The chain lock must be hooked up in a way to avoid sagging of the chain. ATTENTION 3 Application range The maximum allowed operating pressure of 16 bar must not be exceeded! If the above safety instructions are not observed, the sensor in the screw pipe connection may be loosened and thrown out due to the overpressure. The SCHMIDT flow sensor SS is designed for stationary use in pipes conveying gases or gas mixtures which have an oxygen percentage of more than 21 % or pure oxygen. The sensor measures the flow velocity of the measuring medium as standard velocity (unit m/s) relative to the standard pressure of 1, hpa and the standard temperature of 20 C. The output signal is linear and independent of the pressure and temperature of the medium. When mounting the sensor in a tube, the output signal of the flow velocity can be used to calculate the standard volumetric Instructions for Use SS Page 5/16

6 flow or the mass flow of the medium (please refer to the separate table: SS20.60 Profile factors ) When using the sensor outdoors, it must be protected against direct ex-posure to the weather. 4 Determination of the place of installation To reach the accuracy specified in the data sheets, the sensor has to be positioned in a straight conduit and at a place with undisturbed (laminar) flow profile. An undisturbed flow profile can be achieved if a sufficiently long distance in front of the sensor (run-in distance) and behind the sensor (run-out distance) is held absolutely straight and without disturbance sources (such as edges, seams, bends, etc.). The design of the run-out distance is also important, since disturbances do not only act in the direction of the air flow but also lead to turbulences opposite the flow direction. run-in distance L1 L run-out distance L2 D Figure 1: Sensor position in the pipe L = total length of the measuring distance, L1 = length of the runin distance, L2 = length of the run-out distance, D = inner diameter of the measuring distance The sensor tip must be positioned in the center of the pipe, as shown in figure 1. Instructions for Use SS Page 6/16

7 The following table shows the necessary undisturbed conduit lengths depending on the existing flow obstacle. Table of run-in and run-out distances Flow obstacle upstream of the measuring conduit Minimum length of the run-in distance (L1) Minimum length of the run-out distance (L2) Light bend (< 90 ) 10 x D 5 x D Contraction (conduit contracts towards the measuring area) Expansion (conduit expands towards the measuring area) 15 x D 5 x D 15 x D 5 x D 90 bend or T-junction 15 x D 5 x D Two 90 bends in one plane Two 90 bends with 3- dimensional change in direction 20 x D 5 x D 35 x D 5 x D Shut-off valve 45 x D 5 x D Table 1: Run-in and run-out distances This table lists the minimum values required in each case. If the indicated distances cannot be kept, other measures to calm the air flow are required (e.g. flow rectifier). If this is not possible, the measurement accuracy may be impaired. Instructions for Use SS Page 7/16

8 Installation position The sensor should preferably be installed in horizontally positioned pipes. ATTENTION Avoid mounting the sensor in a pipe with downward flow (downdraft). This would considerably increase the lower measuring range limit. 5 Mounting instructions The safety instructions must be observed. 1. Screw the threaded part of the through bolt joint into the pipe union (hexagon AF 27). Unscrew the spigot nut (AF27) to such an extent that the sensor can be inserted without jamming. 2. Insert the sensor up to the desired immersion depth and turn it anti-clockwise by approx. 80 and tighten the spigot nut by hand. Hold the threaded part at the hexagon by means of a fork wrench (AF27). Instructions for Use SS Page 8/16

9 Figure 2: Fixing the sensor in the pipe 3. Tighten the spigot nut by means of a AF24 fork wrench (the sensor turns as well) until the arrow on the sensor housing corresponds to the direction of the pipe flow. The angular deviation should not be greater than 3 referenced to the ideal position. Otherwise the measurement accuracy may be affected. You can check the set angular position by placing a bubble level on the stop face of the housing. In case of a wrong adjustment, unscrew the spigot nut and repeat the mounting procedure as described in item Make sure to close the safety chain before pressure is applied. The chain lock must be hooked up in a way to avoid sagging of the chain. ATTENTION Do not impose any mechanical forces upon the sensors. Never use the stop face for securing and do not try to turn it when the through bolt joint has already been tightened. Otherwise, the housing may be detached from the sensor tube. Instructions for Use SS Page 9/16

10 6 Electrical connections ws bn sw bl Digital + 24 VDC Signal GND Figure 3: Pin assignment SS (View on the pins of the connector at the sensor) The cable supplied has the following color assingment: ws = white, bn = brown, sw = black, bl = blue The minus pole of the supply voltage (GND) is at the same time the reference potential for the analog and digital signal. 7 Startup ATTENTION Only operate the sensor in the defined operating voltage range (24 VDC ± 20 %). Undervoltage may result in malfunction, overvoltage may lead to irreversible damages. The valid measuring range and the configuration of the signal outputs are specified on the rating plate (see housing cover). Note: After applying the supply voltage, the output signal will at first adopt a higher value and then level off at the correct measurement value after about 10 seconds. Instructions for Use SS Page 10/16

11 8 LED display The 4 multi-color LEDs (see figure 7) on the sensor can indicate various information that can be divided in two different types: 1. Flow display: Operation free of errors is indicated by a quasi-quantitative barometrographic flow display in green or orange color. 2. Error signaling: Flashing LEDs in red color (approx. 2 Hz) with error specific patterns. 8.1 Table showing the signaling options No. State, flow 1 LED 1 LED 2 LED 3 LED 4 1 Ready for operation & flow < 5% 2 Ready for operation & flow > 5% 3 Ready for operation & flow > 20% 4 Ready for operation & flow > 50% 5 Ready for operation & flow > 80% 6 Ready for operation & flow > 100% 7 Sensor element defective 8 Operating voltage too low 9 Operating voltage too high 10 Electronic temperature too high 11 Electronic temperature too low Table 1: Signaling of flow and sensor state LED off LED: green LED: orange LED flashes red 1 Accuracy of the flow indication in percent: (2% of final value + 3% of measuring value) Instructions for Use SS Page 11/16

12 8.2 Description of error signaling 1. Malfunction of the sensor element: Synchronous flashing in red of the four LEDs. The measuring function of the sensor is deactivated, that means that both signal outputs are set to zero. Only sensor types with a current interface of 4 20 ma generates a current of 2 ma. The device must be sent to the manufacturer for repair. 2. Inadmissible operating parameters: Synchronous flashing of two LEDs in red showing an error specific pattern. ATTENTION Causes of any error signaling have to be eliminated immediately. A significant exceeding or falling below the permitted operating parameters can result in permanent damage to the sensor. If possible, the measuring function of the sensor is maintained. ATTENTION Inadmissible operating conditions may lead to considerable deviations of the measured values. The error signaling of the LEDs remain active until the cause of the error has been eliminated. Instructions for Use SS Page 12/16

13 9 Service information Recalibration If the customer has made no other provisions, we recommend repeating the calibration at a 12-month interval. To do so, the sensor must be sent in to the manufacturer. Spare parts or repair No spare parts are available since a repair must be carried out by the manufacturer. In case of defects, the sensor must be sent back for repair. When one or several sensors are used in systems important for operation, we recommend keeping a replacement sensor in stock. Test certificates Upon request, we provide, at a charge, a factory calibration certificate, traceable to national standards. Instructions for Use SS Page 13/16

14 10 Technical Specification Messspezifische Daten Measuring value w N Medium to be measured Measuring range of flow w N Lower detection limit w N Messgenauigkeit Standard w N Reproducibility w N Response time t 90 w N Temperature gradient w N Betriebstemperatur Standard velocity w N based on standard conditions of 20 C and 1, hpa Air, Oxygen, nitrogen 0...2,5 / 10 / 20 / 40 / 60 / 120 / 160 / 200 m/s 0,2 m/s ± (3 % of measured value. + 0,4 % of final value) ± 0,5 % of measured value 3 s (jump from 0 to 5 m/s of air) < 8 w N = 5 m/s Sensor C Electronics C Storage temperature C Material Housing Sensor tube, through-bolt joint Sensor head Allgemeine Daten Humidity range Operating pressure Display Anodized aluminum Stainless steel Platinum element (glass passivated), PPO / PA Up to 95 % rel. humidity, non-condensing Max. 16 or 40 bar Supply voltage 24 V DC ± 10 % Current consumption Analogausgang 4 x dual LEDs (green/red/orange) max. 200 ma* - Voltage - Current Maximum load capacitance Connection Maximum cable length Installation position Mounting tolerance Type of protection Protection class 0 10 V RL 10 kω 4 20 ma RL 300 Ω 10 nf Plug-in connector M 12, 8-pin, male, screwed Voltage signal: 15 m, current signal / pulse: 100 m As desired, (for vertical downdraft flow: lower range limit 2 m/s at 16 bar) ± 5 to flow direction IP 65 (housing), IP 67 (sensor) III (SELV) bzw. PELV Instructions for Use SS Page 14/16

15 11 Declaration of conformity Instructions for Use SS Page 15/16

16 SCHMIDT Technology GmbH Feldbergstrasse 1 D St. Georgen Phone +49 (0)7724/899-0 Fax +49 (0)7724/ info@schmidttechnology.de Instructions for Use SS Page 16/16