User’s Manual Model AC4/AC8 Automatic Calibration Unit For Use With AV550G Oxygen Analyzer Averaging Converter IM 11M6D2-02E-A 3rd Edition
User’s Manual I. II. Model AC4/AC8 Automatic Calibration Unit For Use With AV550G Oxygen Analyzer Averaging Converter Introduction.................................................................................................3 Overview......................................................................................................3 2.1 Models AC4/AC8 Multi-Channel Automatic Calibration...............................................................3 III. Installation..............................
I. INTRODUCTION This manual details the operating instruction for the Yokogawa Model AC4/AC8 Automatic Calibration Unit, and the integration with the AV550G Zirconia Oxygen Averaging Converter. IMPORTANT The maximum input pressure for the span and zero gases is 35 psig. Exceeding 35 psig may result in damage to the AC4/AC8. II.
Figure 3.1: AC4/AC8 Dimensional Drawing 3.3 GAS SOURCES Zero Gas Typically, 1% oxygen balanced in nitrogen is used, however, an oxygen mixture between 0.5% and 8% is acceptable. NEVER USE PURE NITROGEN FOR ZERO CALIBRATION GAS. A compressed gas cylinder containing the zero gas is fitted with a dual stage regulator. Zero calibration gas cylinders with regulators may be purchased from a local compressed gas supplier. Follow the operation and safety instructions as supplied from your gas supplier.
3.4 PIPING /-2ĥ DCK?JC LNR PCD E?Q PROBE 1 A?J E?Q LCK? 2V /-2ĥ DCK?JC LNR PROBE 2 O2 CALIBRATION SYSTEM INSTRUMENT AIR PROBE 3 PROBE 4 PROBE 5 ZERO GAS 35 psig MAX PROBE 6 WMIME?U? PROBE 7 PROBE 8 Figure 3.2 Piping Gases to the Auto Cal Unit Piping (or tubing) is required from the instrument air line and zero gas cylinder to the calibration unit. Standard tubing is _” O.D. (Outside Diameter) copper or stainless steel. Stainless steel is preferred, as it is less likely to develop leaks.
IV. WIRING Calibration Using Pressure Switch AND Relay 4.1 Wiring the AC4/AC8 to the AV550G Averaging unit Pre ssure Switch Please refer to appendix A for the system configuration drawing. YES Cal Gas Pre ssure OK ? STAR T NOTE A 120 VAC relay (included with NEMA 4 enclosure), shown at terminal K1, is required at the AV550G if a pressure switch is used. This prevents noise caused by a low voltage pressure switch signal from being run in the same cable as the 120 VAC solenoid signal.
For setting on fall, apply pressure equal to normal system operating pressure. Reduce source pressure to set point value. Turn the adjustment clockwise until switch “clicks” [circuit across N.C. (black) and COM (white) closes]. For setting on rise, apply desired pressure and turn adjustment left until switch “clicks” [circuit across N.O. (red) and COM (white) terminal closes]. 5. After completing adjustments, slide the cover closed over the adjustment compartment. Recheck the set point value. 6.
5.3 BALANCING PRESSURE DROPS IN THE CAL LINES For accurate calibrations, the auto cal system must provide a fixed flow of zero gas and span gas (0.6 LPM pr 600cc/min). To do this, the pressure drop from the AC4/AC8 to each probe must be the same regardless of the length of tubing run or number of probes. To balance the pressure drops, perform the following steps: 6. Turn the manual override on the channel solenoid for the probe to the OFF (normal) position. 7.
11. Turn the block solenoid and the zero/span solenoid to the normal position. WARNING If reference air is used during calibration, the reference air must remain ON after calibration. FLOW ADJUSTMENT SCREW (PRESET) FOR NORMAL OPERATION THE MANUAL OVERRIDE SCREW MUST BE IN THE VERTICAL POSITION FOR OVERRIDE THE MANUAL OVERRIDE SCREW MUST BE IN THE HORIZONTAL POSITION Item Mode Points Zero gas conc. Span gas con. Hold time Cal.
7.1.3 Zero Gas Concentration This sets the oxygen concentration of the zero gas used for calibration. Enter the value from the label of the corresponding gas bottle. 7.1.4 Span Gas Concentration This sets the oxygen concentration of the span gas used for calibration. When the instrument air supply is used as the span gas, enter 21% O2. NOTE Figure 7.1 Calibration Mode Setting 7.1.2 Calibration Setup Procedure Either Span or Zero or both calibrations can be performed. Normally select both: Span-Zero.
Cal start in Chan 1 Span CAL CAL time Chan 1 Zero CAL CAL time Chan 1output hold Stabilization Chan 1 output hold Chan 2 Span CAL CAL time Chan2 Zero Cal CAL time Chan 2 output hold Stabilization Chan 2 output hold Chan 1 removed from average Average output SV-Chan 1 contact off on off SV- Chan 2 contact SV- Chan 2 contact Chan 2 removed from average span gas on zero gas on on span gas on zero gas on CAL start Figure 7.
3) If the calibration interval is shorter than the sum of the stabilization time plus calibration time, the second calibration start time will conflict with the first calibration. In such a case, the second calibration will not be conducted. (When both zero and span calibrations are to be performed, the calibration time is double that required for a single (zero or span) calibration). 4) If the (Calibration) Interval is et to DD: 00, HH: 00 then auto Calibration will not be performed.
X. SPARE PARTS AND ACCESSORIES 10.1 SPARE PARTS Refer to figure 10.1 for a list of replacement parts for the AC4/ AC8 Auto Calibration Unit. CH AN NE L MA N IF OLD WIT H M ANU AL O VE R RIDE AN D FLOW A DJU STE R M1133BY (4 Chan nel) M1133BZ (8 C ha nne l) Figure 10.1 1. Zero/Span Solenoid 2. Channel Manifold M1132GM M1133BY (4 CHANNEL) M1133BZ (8 CHANNEL) 3. Needle Valve M1132GK (BRASS) M1132BX (STAINLESS STEEL) 4.
10.2 ACCESSORIES 10.2.1 Zero Gas Regulator, M1132ZX This regulator controls the gas pressure of the zero gas cylinders before it reaches the calibration unit. The dual stage regulator is highly recommended for services which require a near constant delivery pressure as the calibration source decays (See M1133AR). Air diffusion and absorption, desorption and off gassing are minimized because of its stainless steel construction.
10.2.2 Pressure Regulator, M1132KD This general purpose regulator is used to adjust the pressure of instrument air entering the AC4/AC8. Figure 10.4 Figure 10.4 Pressure Regulator, M1132KD Flow Capacity: 20 SCFM (33.6m_/hr) at 100 psig supply – 20 psig outlet Exhaust Capacity: 0.1 SCFM (0.17m_/hr) – downstream pressure 5 psig above set point Sensitivity: 1” of water Effect of Supply Pressure Variation: Less than 0.
10.2.4 Zero Pressure Switch, M1133AR, Figure 10.2.6 The pressure switch is used to alert the Operator via a contact input that the zero gas cylinder needs to be replaced before the cylinder is empty. The recommended connection is to the high pressure side of the zero gas regulator. Refer to Figure 4.1. Figure 10.2.
APPENDIX A IM 11M6D2-02E-A
IM 11M6D2-02E-A
APPENDIX B IM 11M6D2-02E-A
IM 11M6D2-02E-A
