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Operating and Maintenance Instructions
Part Number- 3-9008-556 Revision D
December 2012
TM
Daniel Model 788 DVC digital control
valves
2", 3", 4", 6" and 8" sizes
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Important safety instructions Daniel Measurement and Control, Inc. (Daniel) designs, manufactures and tests products to function within specific conditions. Because these products are sophisticated technical instruments, it is important that the owner and operation personnel strictly adhere both to the information printed on the product nameplate and to all instructions provided in this manual prior to installation, operation, and maintenance. Daniel also urges you to integrate this manual into
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Product operation personnel: • To prevent personal injury, personnel must follow all instructions of this manual prior to and during operation of the product. • Follow all warnings, cautions, and notices marked on, and supplied with, this product. • Verify that this is the correct instruction manual for your Daniel product. If this is not the correct documentation, contact Daniel at 1-713-827-6314. You may also download the correct manual from: http://www.daniel.com • Read and understand all in
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Safety signal words and symbols Pay special attention to the following signal words, safety alert symbols and statements: Indicates a hazardous situation which, if not avoided, will result in death or serious injury. Warning indicates a hazardous situation which, if not avoided, could result in death or serious injury. Caution indicates a hazardous situation which, if not avoided, could result in minor or moderate injury. Notice is used to address safety messages or practices not related to pers
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Notice THE CONTENTS OF THIS PUBLICATION ARE PRESENTED FOR INFORM ATIONAL PURPOSES ONLY, AND WHILE EVERY EFFORT HAS BEEN MADE TO ENSURE THEIR ACCURACY, THEY ARE NOT TO BE CONSTRUED AS WARRANTIES OR GUARANTEES, EXPRESSED OR IMPLIED, REGARDING THE PRODUCTS OR SERVICES DESCRIBED HEREIN OR THEIR USE OR APPLICABILITY. ALL SALES ARE GOVERNED BY DANIEL’S TERMS AND CONDITIONS, WHICH ARE AVAILABLE UPON REQUEST. WE RESERVE THE RIGHT TO M ODIFY OR IM PROVE THE DESIGNS OR SPECIFICATIONS OF SUCH PRODUCTS AT A
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Warranty and limitation of liability 1. LIMITED WARRANTY: Subject to the limitations contained in Section 2 herein, Daniel Measurement & Control, Inc. (“Daniel”) warrants that the licensed firmware embodied in the Goods will execute the programming instructions provided by Daniel, and that the Goods manufactured by Daniel will be free from defects in materials or workmanship under normal use and care and Services will be performed by trained personnel using proper equipment and instrumentation
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 TABLE OF CONTENTS 1.0 INTRODUCTION ..................................................... 1-1 1.1 Aggressive Products .............................................. 1-1 1.2 Principle of Operation ............................................ 1-2 2.0 THEORY OF OPERATION ............................................. 2-1 2.1 Operational Sequence ............................................ 2-1 3.0 SPECI FI CATI ONS ...............................
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES Figures 2-1 Closed Position ....................................................... 2-2 2-2 Open - Control Position ................................................. 2-3 2-3 Open Position (no control)............................................... 2-4 3-1 Flow vs Pressure Drop .................................................. 3-3 3-2 Dimensions .......................................................... 3-6 4-1 Typical Application - Bottom L
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 1.0 INTRODUCTION TM The Daniel Model 788DVC Digital Control Valve is a solenoid operated device designed to provide precise flow rate control and batch delivery of liquid products. It is used in conjunction with an electronic batch control device such as the Daniel DL8000. The Model 788DVC valve is automatically controlled by the DanLoad for low flow start-up, high flow rate control, low flow shut-down, and final shut-off. It also provides f
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES 1.2 Principle of Operation Operation of the Model 788DVC Digital Control Valve is based on a balanced piston principle. When pressure on both sides of the main valve piston are equal, a spring (located on the top of the piston) acts as a differential force and closed the main valve piston. As pressure against the bottom of the piston increases and exceeds the pressure exerted against the top of the piston, plus the force of the spring, sprin
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 2.0 THEORY OF OPERATION The Model 700B Series Control Valve operates on a balanced-piston principle. When pressures on both sides of the piston are equalized, a spring located on top of the piston acts as a differential force and closes the piston. When the pressure against the bottom of the piston exceeds the pressure plus the force of the spring exerted against the top of the piston, spring tension is overcome, and the valve opens. See Fig
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES CLOSED POSITION - The normally closed solenoid is closed. The normally open solenoid is open. Y-port (P3) to Z-port (P2) is closed. X-port (P1) and Y-port (P3) pressures are balanced. The main valve spring being the differential force, closes the piston and keeps it seated. Figure 2-1. Closed Position 2-2 THEORY OF OPERATION
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 OPEN - CONTROL POSITION - The normally closed solenoid is closed. The normally open solenoid is closed. Y-Port (P3) to Z-port (P2) is closed. X-port (P1) to Y-port (P3) is closed. The product cannot flow to or from the top of the piston. The piston is hydraulically locked in position until the electronic preset commands the valve to open or close as required to maintain the desired high flow rate, or low flow rate. Figure 2-2. Open - Contr
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES OPEN POSITION - (no control) - The normally closed solenoid is open. The normally open solenoid is closed. Y-port (P3) is open to Z-port (P2). X-port (P1) is closed off by the normally open solenoid. The pressure on the bottom of the piston (P1) is greater than the pressure at (P3) plus the spring force; (P1 minus P2) is equal to or greater than the spring force. Therefore, (P1) pressure pushes the piston open. No flow control is required.
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 3.0 SPECIFICATIONS PERSONAL INJURY AND/OR EQUIPMENT DAMAGE Do not exceed specifications listed below. Failure to heed this warning could result in serious injury and/or damage to the equipment. Pressure Class 150 lb., 300 lb., or 600 lb. ANSI steel DIN PN 16, 40, 64, and 100 Safe Working Temperature Ranges Standard: -20/F, -29/C to 150/F, 66/C Optional: -20/F, -29/C to 250/F, 121/C Maximum Safe Working Pressure 150 lb. ANSI steel body - 285
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES INMETRO Certification: - Certificate Number: NCC 12.1244 X - INMETRO Marking: Ex d nC IIB T3 Gc Ex d IIC T* Gb *See Tables 1 and 2 in the certificate for temperature range details. Special condition for safe use: When the digital control valve is assembled with solenoid models 80174, 80173, 80143, 80144, HP80143, 8014G2 and F8003G1, the temperature of the process fluid must not be greater than 40°C. Connections 2" through 6" ANSI flanged Val
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TM DANIEL MODEL 788DVC DIGITAL CONTROL VALVES DEC 2012 The main valve is full open when curves B, C, and D intersect Curve A. After they intersect, continue reading pressure drop curve from curve A. In applications requiring a constant pressure drop over 40 psid a heavy main valve spring must be used. Curves A, B, C and D are based on water (specific gravity: 1.0). For liquids having a specific gravity of 0.8 or greater, multiply the pressure drop shown times the actual specific gravity. This re
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TM DEC 2012 DANIEL MODEL 788DVC DIGITAL CONTROL VALVES Materials of Construction Main Valve Body steel, ASTM-352 LCC Cylinder Head steel, ASTM-352 LCC Main Valve Cylinder steel nickel coated steel Main Valve Piston Standard: stainless steel Seat Ring steel nickel coated steel Seals steel O-rings ® Standard: Viton dynamic, Buna-N ®® ® Optional: EPR, Kalrez , Low-Swell Nitrile, Neoprene™, Viton -A, Viton -GFLT Optional Visual position indicator Microswitch-type indicator AP (aggressive products
