TetraTec Instruments GmbH Gewerbestrasse 8 71144 Steinenbronn Deutschland E-Mail: info@tetratec.de Tel.: 07157/5387-0 Fax: 07157/5387-10 MANUAL Pressure Control Valve *** VERSION 1.0 *** Update: 17.11.2006
GENERAL DESCRIPTION... 3 EXTENT OF SUPPLY... 3 TECHNICAL DESCRIPTION... 3 SPECIFICATIONS... 3 INSTALLATION... 4 PNEUMATIC INSTALLATION... 5 FUNCTION OF TRIMMERS AND JUMPERS... 6 OPERATION... 7 DIMENSIONS... 8 page 2 _man_e.doc
GENERAL DESCRIPTION Pressure control valve in nominal widths of 4 and 6 mm Control range from 0,9 bar to 10 bar gauge pressure Flow rate up to 780 Sl/min (NW6) Response time of 5 ms Option for internal or external pressure sensor EXTENT OF SUPPLY 1x Servo-valve 3/x with mounting plate with G1/4 connections 1x plug 7-pin for Supply Manual Option: 1x plug 4-pin for pressure transducer TECHNICAL DESCRIPTION The pressure control valve controls ranges from 0,9 bar vacuum pressure to 10 bar gauge pressure. The 3-way principle allows it to mix inlet pressures according to the position of the control valve. Available is it in the nominal widths of 4 and 6 mm ( 3/4 and 3/6). Those both versions are precision pressure controller pneumatically and electronically ready to connect. The servo valves combine highest controlling accuracy with fast response time. The pressure servo valves unite in one enclosure a servo valve cartridge, a pieco resistive pressure chamber, an electronical PID-pressure controller such as the electronical attitude control and power setting for the servo valve. Optionally it is possible to abjure on the internal pressure sensor for connecting an external pressure sensor. The actual value is put out analogue. Furthermore there are two process connection available. SPECIFICATIONS Pressure Control Range Pressure control range: 0,9 bar vacuum pressure to 10 bar gauge pressure Input pressure: > 150 % F.S. (max. 10 bar) Accuracy Linearity and Hysteresis: respectively <1 % Measuring Accuracy: 1 % F.S. Control Accuracy: 0,1 % F.S. corresponding to the sensor output signal Repeatability: < 0,03 %F.S. Limit frequency: appr. 70Hz @100% activation appr. 110Hz @50% activation Operating Conditions Operating Pressure: 0,9 bar vacuum pressure to 10 bar gauge pressure Temperature: 0... +50 C Humidity: 0...90 % R.H.non-condensing Media Compatibility Clean, dry, oil-free air with 5 µm filtered; humidity non-condensing Flow Behaviour Flow at Nominal width 4 mm Nominal width 6 mm 6 vs. 5 bar: 300 Sl/min 450 Sl/min 6 vs. 0 bar: 550 Sl/min 780 Sl/min Kv-Value: 0,48 0,70 Air Consumption.: < 6,5 Sl/min < 10 Sl/min Approximated flows when completely opened at nominal conditions (1013 mbar abs., 0 C, 0 % R.H.) _man_e.doc page 3
Enclosure Dimensions: Absolute: HxWxD: 85x60x100mm Housing: HxWxD: 60x60x100mm Mounting plate: HxWxD: 25x80x60mm Material: Housing: Aluminium, anodised Valve Cartridge: stainless steel Weight: Total: 1 kg Ingress Protection: IP 20 Process Connection (mounting plate) G 1/4 female thread Electrical Connection Coupling socket 7pole Connection 4pole for external pressure transmitter (optionally) Electrical Data Power: 24 VDC +/-10%, smoothed, max. 0,8 A ripple max. 0,5 Vss. Controlling: By voltage standard signals Set-point value input: 0 to 10 VDC at appr. 50 kω 0 to 20 ma at 500 Ω (optionally) Actual value output: 0 to 10VDC LIMIT/ERROR-Output: Open-collector to GND, max. 20mA, not short-circuit proof External Pressure Transducer Output Supply: Actual Value Input: INSTALLATION Approx. 24 VDC, max. 100 ma 0 to 10 VDC at 100 kω 0 to 20 ma at 500 Ω (optionally) 4 to 20 ma at 625 Ω (optionally Electrical Installation (pin assignment): Supply connector (7-pin male, No.1 in figure 1) Pin Function Remarks 1 Power supply +24 VDC 2 Power supply GND 3 Input specified value + (0 10 VDC resp. 0 20 ma) 4 Input set-point value (GND) 5 Output Error See technical data 6 Output Limit See technical data 7 Output actual value + (0 10 VDC at Pin2) The total range of this signal corresponds to the total range of the sensor for the real value. The output pressure follows always this signal. Therefore the signal has to have a high signal quality: if, for example, the sensor has a range of 10 bar, a ripple of 10mV on the specified value will generate a ripple of 10 mbar on the output pressure. Pin 4 and Pin 2 should be connected. If that is not possible, the voltage between both GND s may not increase +/-30 V The accuracy fault of that signal is about 2% and there is an offset of approx. 150 mv. Don t use it for precise documentations. The accuracy of controlling itself is much better. page 4 _man_e.doc
Connector for external pressure transmitter Only for valves 3/x-00 (4-pin female, No.2 in figure 1) Pin Function remarks 1 Output approx. 24 VDC at Pin 2 Transmitter supply 2 GND Same as power supply GND 3 Input actual value 0 10 V or 0 20 ma at Pin 2 or 4 20 ma 4 Not connected PNEUMATIC INSTALLATION Normally the valves are installed as drawn in figure 2 and figure 3. For with internal sensor the tubes to the load should be as short as possible (not more than 2m). They must have an inner diameter acc. to the size of the valves (4mm resp. 6mm) to prevent pressure drops. The valves are optimally adjusted by the factory for closed load volumes (no permanent air consumption) of approx. 0.25l to 2 l. figure2: precision pressure control by and internal pressure sensor figure 3: precision pressure control with and external pressure transducer _man_e.doc page 5
FUNCTION OF TRIMMERS AND JUMPERS Feedback parameter adjustments (PCB DR2) Function Remarks TR1 P adjustment: proportional feedback Kp For all feedback adjustments: Turning clockwise: Feedback is increased TR2 I adjustment: integral feedback Ki Turning counter-clockwise: Feedback is decreased TR3 D adjustment: differential feedback Kd Binary signal adjustments (PCB DR2) Function Remarks TR4 LIMIT Output signal LIMIT If the real value exceeds a value defined by TR4 between 0 and 100% of the total range of the actual value, the signal LIMIT appears (output npn-transistor to Not adjustable Output signal ERROR GND is switched on). If the system is not able to reach the specified value within approx. 5s the signal ERROR appears (output npn-transistor to GND is switched on) page 6 _man_e.doc
General adjustments (PBC VE2) Function Remarks Jumper Feedback loop open/closed Normally don t open! UA standard: closed (necessary for normal operation) J1-3 Setting of valve position after power down: Position - closed: valve output is pressurized Position + closed: valve output is exhausted Position N closed: valve in neutral position (closed) T1,T2 Basic adjustments of the valve Don t disadjust! OPERATION The valves are optimally adjusted by the factory for closed load volumes (no permanent air consumption) of approx. 0,25l to 2l. Modify the adjustments only for other kinds of load systems. 1. Adjusting of systems with closed load volumes (no permanent air consumption) 1.1 Normally bring all parameter feedbacks (TR1 TR3) to zero (turning counter-clockwise at least 15 turns). 1.2 Feed specified value with a rectangle signal, frequency approx. 0,3 Hz, low voltage 2 V (that means 20 % of maximum pressure), high voltage 8V (that means 80% of maximum pressure) 1.3 Increase feedback parameter Kp (proportional feedback, TR1 Feedback parameter adjustments ) until the output pressure overshoots. 1.4 Increase feedback parameter Kd (differential feedback, TR3 Feedback parameter adjustments ) until the overshoot is damped 1.5 In systems with closed load volumes normally the I-feedback Ki ( integral feedback, TR2 Feedback parameter adjustments ) is not necessary. With I-feedback low frequent oscillations at the output may appear. 1.6 Repeat steps 1.3 to 1.4 until the optimal control behaviour is reached. 1.7 Check the adjustments with other specified values, if necessary, repeat step 1.6 1.8 Check LIMIT -output if used in your application. Use TR4 for adjusting desired limit for switching. ( Binary signals adjustments ) _man_e.doc page 7
2. Adjusting of systems with open load volumes (permanent air consumption) 2.1 Normally bring all parameter feedbacks (TR TR3) to zero (turning counter-clockwise at least 15 turns) 2.2 Feed specified value with a rectangle signal, frequency approx. 0,3 Hz, low voltage 2 V (that means 20% of maximum pressure), high voltage 8V (that means 80% of maximum pressure). 2.3 Increase feedback parameter Kp (proportional feedback, TR1 Feedback parameter adjustments ) until the output pressure reacts. 2.4 Increase feedback parameter Ki (differential feedback, TR2 Feedback parameter adjustments ) until the output pressure overshoots. 2.5 Increase feedback parameter Kp (proportional feedback, TR1 Feedback parameter adjustments ) until the overshoot is damped. 2.6 If necessary, increase feedback parameter Kd (differential feedback, TR3 Feedback parameter adjustments ) to optimize control behaviour. Normally in this mode of operation there is no need for the differential feedback. 2.7 Optimize the adjustments acc. to steps 1.7 to 1.8. ATTENTION: AVOID PERMANENT OSCILLATIONS OF THE CONTROLLER (IDENDTIFIABLE BY CLEARLY AUDIBLE, HAMMERING NOISE). IN THIS CASE DECREASE THE FEEDBACK-PARAMETERS UNTIL THE OSCILLATIONS DISAPPEAR. DIMENSIONS Dimension data in mm-units. page 8 _man_e.doc