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The process measurement, set point, and output signal are indicated on the controller. Traceability to individual heat numbers is not available and the non-specific material certificates are not supplied. This certificate does not include resale options such as seals and bypass manifolds. CERT-C is signed and dated by the appropriate Quality Engineer or other qualified personnel. NIST was formerly called the National Bureau of Standards (NBS). The test pressure depends on the Maximum Working Pressure (MWP) of the instrument. Test pressure equals 1.5 times MWP for MWP of 100 to 5000 psi (0.7 to 35 MPa), 1.4 times MWP for MWP over 5000 and up to 10000 psi (35 to 70 MPa), 1.3 times MWP for MWP over 10000 and up to 20000 psi (70 to 140 MPa), 1.2 times MWP for MWP over 20000 and up to 25000 (140 to 175 MPa), and 1.1 times MWP for MWP over 25000 psi (175 MPa). Note: The cleaning option (OS-W, OS-FC, CLS, etc.) must be added to the base instrument. Refer to appropriate instrument sections of Price Book. Includes the signature of the Manager of Product Qualification. Provide PMI testing and certificate stating that the pressure wetted material(s) on this order are in conformance with the applicable ASTM standards.Provide PMI testing and certificate stating that the pressure containment material(s) on this order are in conformance with the applicable ASTM standards.Markings Can Be Up To 10 Lines, 40 Characters Or Spaces Per Line. Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).One Signal Relay Energized On Decreasing Measurement.
One Signal Relay Energized On Increasing Measurement. One Control Relay Energized On Decreasing Measurement. One Control Relay Energized On Increasing Measurement. Two Signal Relays Both Energized On Decreasing Measurement. Two Signal Relays Both Energized On Increasing Measurement. Two Signal Relays One Energized On Increasing And One On Decreasing Measurement. One Control And One Signal Relay, Both Energized On Decreasing Measurement. One Control And One Signal Relay, Both Energized On Increasing Measurement. One Control Relay Energized On Decreasing And One Signal Relay Energized On Increasing Measurement. One Control Relay Energized On Increasing And One Signal Relay Energized On Decreasing Measurement. Two Control Relays Both Energized On Decreasing Measurement. Two Control Relays Both Energized On Increasing Measurement. Two Control Relays, One Energized On Increasing And One Energized On Decreasing Measurement. Three Signal Relays Energized On Decreasing Measurement. Three Signal Relays Energized On Increasing Measurement. Three Signal Relays, Two Energized On Decreasing And One Energized On Increasing Measurement. Three Signal Relays, Two Energized On Increasing And One Energized On Decreasing Measurement. One Control And Two Signal Relays All Energized On Decreasing Measurement. One Control And Two Signal Relays All Energized On Increasing Measurement. One Control And One Signal Relay Energized On Decreasing Measurement, And One Signal Relay Energized On Increasing Measurement. One Control And One Signal Relay Energized On Increasing Measurement, And One Signal Relay Energized On Decreasing Measurement. Refer to CES 260 Refer to CES 260 Refer to CES 260 Traceability to individual heat numbers is not available and the non-specific material certificates are not supplied. Test pressure equals 1.5 times MWP for MWP of 100 to 5000 psi (0.7 to 35 MPa), 1.4 times MWP for MWP over 5000 and up to 10000 psi (35 to 70 MPa), 1.
3 times MWP for MWP over 10000 and up to 20000 psi (70 to 140 MPa), 1.2 times MWP for MWP over 20000 and up to 25000 (140 to 175 MPa), and 1.1 times MWP for MWP over 25000 psi (175 MPa). Note: The cleaning option (OS-W, OS-FC, CLS, etc.) must be added to the base instrument. Refer to appropriate instrument sections of Price Book. Includes the signature of the Manager of Product Qualification. Provide PMI testing and certificate stating that the pressure wetted material(s) on this order are in conformance with the applicable ASTM standards.Provide PMI testing and certificate stating that the pressure containment material(s) on this order are in conformance with the applicable ASTM standards.Markings Can Be Up To 10 Lines, 40 Characters Or Spaces Per Line. Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 50 Feet (15 m).Tubing, Flexible Stainless Over Stainless Capillary, Length 100 Feet (30 m).One Signal Relay Energized On Decreasing Measurement. One Signal Relay Energized On Increasing Measurement. One Control Relay Energized On Decreasing Measurement. One Control Relay Energized On Increasing Measurement. Two Signal Relays Both Energized On Decreasing Measurement. Two Signal Relays Both Energized On Increasing Measurement. Two Signal Relays One Energized On Increasing And One On Decreasing Measurement. One Control And One Signal Relay, Both Energized On Decreasing Measurement. One Control And One Signal Relay, Both Energized On Increasing Measurement. One Control Relay Energized On Decreasing And One Signal Relay Energized On Increasing Measurement. One Control Relay Energized On Increasing And One Signal Relay Energized On Decreasing Measurement.
Two Control Relays Both Energized On Decreasing Measurement. Two Control Relays Both Energized On Increasing Measurement. Two Control Relays, One Energized On Increasing And One Energized On Decreasing Measurement. Three Signal Relays Energized On Decreasing Measurement. Three Signal Relays Energized On Increasing Measurement. Three Signal Relays, Two Energized On Decreasing And One Energized On Increasing Measurement. Three Signal Relays, Two Energized On Increasing And One Energized On Decreasing Measurement. One Control And Two Signal Relays All Energized On Decreasing Measurement. One Control And Two Signal Relays All Energized On Increasing Measurement. One Control And One Signal Relay Energized On Decreasing Measurement, And One Signal Relay Energized On Increasing Measurement. One Control And One Signal Relay Energized On Increasing Measurement, And One Signal Relay Energized On Decreasing Measurement. Refer to CES 260 Refer to CES 260 Refer to CES 260. This versatility enables the 43AP Series Pneumatic Indicating Controllers to be applied to virtually any process. Wide choice of control modes On-off, proportional, proportional plus derivative, proportional plus integral (reset), proportional plus integral plus derivative, differential gap, and automatic shutdown actions are available. Broad range of integral (reset) and derivative adjustments The integral unit has the complete range from 0.01 to 50 minutes, and the derivative unit from 0.05 to 50 minutes. Variety of options These controllers are available with an extensive list of optional features. Among these are internal bumpless automatic-manual transfer stations (two types), “batch” function, remote pneumatic set point, Type 70 electric contacts, and control valve mounting. Accuracy unaffected by mounting stresses Both the control unit and the measurement element are mounted on a rigid steel plate.
Thus, these components are isolated from case stresses due to mounting, and dependable accuracy is ensured. Call an expert now to check availability or answer your technical questions. Call 01246 551 839 Alternatively you can complete the form on the right and an expert will be in touch. Full 2-year service warranty from date of installation. - 43AP-FA42C-PB-BA-20 Valves Depot is not an FM Approved Repair Facility and cannot supply remanufactured or repaired FM Approved equipment for Hazardous Locations. And by having access to our ebooks online or by storing it on your computer, you have convenient answers with Foxboro 43ap Maintenance Manual. To get started finding Foxboro 43ap Maintenance Manual, you are right to find our website which has a comprehensive collection of manuals listed. Our library is the biggest of these that have literally hundreds of thousands of different products represented. I get my most wanted eBook Many thanks If there is a survey it only takes 5 minutes, try any survey which works for you. Let us give you a quote for exactly what you need. Call us at the number above, or fill out this form and we’ll get back to you shortly. Please be sure to include the model number if you have it. Please leave this field empty. Their flexibility of use makes these instruments applicable to essentially any process.To shield the control unit and measurement element from the effects of case stresses caused by mounting, and thus, maintain precision during use, both components are mounted on a firm steel plate. To get to the transfer station, the door must be opened, thus preventing unintentional transfer. This mechanism does not directly correspond to any particular manufacturer or model of pneumatic controller, but shares characteristics common to many. This design is shown here for the purpose of illustrating the development of P, I, and D control actions in as simple a context as possible.
Increasing process variable (PV) pressure attempts to push the right-hand end of the beam up, causing the baffle to approach the nozzle. This blockage of the nozzle causes the nozzle’s pneumatic backpressure to increase, thus increasing the amount of force applied by the output feedback bellows on the left-hand end of the beam and returning the flapper (very nearly) to its original position. If we wished to reverse the controller’s action, all we would need to do is swap the pneumatic signal connections between the input bellows, so that the PV pressure was applied to the upper bellows and the SP pressure to the lower bellows. Changing bellows area (either both the PV and SP bellows equally, or the output bellows by itself) would influence this ratio, as would a change in output bellows position (such that it pressed against the beam at some difference distance from the fulcrum point). Moving the fulcrum left or right is also an option for gain control, and in fact is usually the most convenient to engineer. This means any given change in input (PV or SP) force is more difficult for the output bellows to counterbalance. The output pressure, therefore, must change to a greater degree in order for this force-balance mechanism to achieve balance. A greater change in output pressure for a given change in input pressure is the definition of a gain increase. This additional leverage makes it easier for the output bellows to counter-act changes in input force, resulting in less output pressure change required to balance any given input pressure change. A lesser change in output pressure for a given change in input pressure is characteristic of a gain decrease. In contrast to a force-balance system where opposing forces cancel each other to restrain motion of the mechanism, a motion-balance system freely moves as the signal pressures traverse their working ranges.
A simple motion-balance proportional controller design appears here: This motion draws the lever away from the nozzle, resulting in decreased nozzle backpressure. This behavior identifies this controller as reverse-acting. If direct action were desired, all we would need to do is swap the process variable and setpoint input pressure connections. However, it must be understood that this position change will have the opposite effect on gain compared with the fulcrum position change described for the force-balance mechanism. Here in the motion-balance system, it is the relative travel of each bellows that matters for gain, not the relative leverage (torque): The output pressure in this case will change only slightly for large changes in PV or SP pressures: characteristic of a low gain. The output bellows must expand and contract quite a bit more than the input bellows in order to maintain a constant nozzle gap for any motion at the input side. This requires a greater change in output pressure for a given change in input pressure: the definition of increased gain. Without provision for bumpless transfer, the output signal of the controller may suddenly change whenever the mode is switched between automatic and manual. This sudden signal change will cause the final control element to suddenly “step” to some new level of effect on the process. When in automatic mode, a switch to manual mode involves adjusting the output regulator until the balance indicator registers zero pressure difference, then switching the transfer valve to the “manual” position. The controller output is then at the direct command of the output adjust pressure regulator, and will not respond to changes in either PV or SP. “Bumplessly” switching back to automatic mode requires that the setpoint pressure regulator be adjusted until the balance indicator once again registers zero pressure difference, then switching the transfer valve to the “auto” position.
The controller output will once again respond to changes in PV and SP. To center the ball while in automatic mode, the manual output pressure must be adjusted to achieve balance with the automatic-mode output pressure.All we need to do is place a restrictor valve between the nozzle tube and the output feedback bellows, causing the bellows to delay filling or emptying its air pressure over time: Thus, the output pressure “spikes” with any sudden “step change” in input: exactly what we would expect with derivative control action. Thus, derivative action causes the output pressure to shift either up or down (depending on the direction of input change) more than it would with just proportional action alone in response to a ramping input: exactly what we would expect from a controller with both proportional and derivative control actions. At first, this may seem counter-productive, for it nullifies the ability of this mechanism to continuously balance the force generated by the PV and SP bellows. Indeed, it would render the force-balance system completely ineffectual if this new “reset” bellows were allowed to inflate and deflate with no time lag. However, with a time lag provided by the restriction of the integral adjustment valve and the volume of the bellows (a sort of pneumatic “RC time constant”), the nullifying force of this bellows becomes delayed over time. As this bellows slowly fills (or empties) with pressurized air from the nozzle, the change in force on the beam causes the regular output bellows to have to “stay ahead” of the reset bellows action by constantly filling (or emptying) at some rate over time. The following mechanism has been stripped of all unnecessary complexity so that we may focus on just the proportional and integral actions.
Here, we envision the PV and SP air pressure signals differing by 3 PSI, causing the force-balance mechanism to instantly respond with a 3 PSI output pressure to the feedback bellows (assuming a central fulcrum location, giving a controller gain of 1). The reset (integral) valve has been completely shut off at the start of this thought experiment: The mechanism is a simple proportional-only pneumatic controller. As the reset bellows fills with pressurized air, it begins to push down on the left-hand end of the force beam. This forces the baffle closer to the nozzle, causing the output pressure to rise. The regular output bellows has no restrictor valve to impede its filling, and so it immediately applies more upward force on the beam with the rising output pressure. With this greater output pressure, the reset bellows has an even greater “final” pressure to achieve, and so its rate of filling continues. This creates a constant 3 PSI differential pressure across the reset restriction valve, resulting in a constant flow of air into the reset bellows at a rate determined by that pressure drop and the opening of the restrictor valve. Eventually this will cause the output pressure to saturate at maximum, but until then the practical importance of this rising pressure action is that the mechanism now exhibits integral control response to the constant error between PV and SP: Thus, we see in this mechanism the defining nature of integral control action: that the magnitude of the error determines the velocity of the output signal (its rate of change over time, or \(dm \over dt\)). The rate of integration may be finely adjusted by changing the opening of the restrictor valve, or adjusted in large steps by connecting capacity tanks to the reset bellows to greatly increase its effective volume.
Proportional and integral control modes are implemented through the actions of four brass bellows pushing as opposing pairs at either end of a beam: Setpoint control is achieved by moving the position of the nozzle up and down with respect to the beam. A setpoint dial (labeled “Increase Output Pressure”) turns a cam which moves the nozzle closer to or farther away from the beam. This being a motion-balance system, an offset in nozzle position equates to a biasing of the output signal, causing the controller to seek a new process variable value. Integral rate control is implemented exactly the same way as in the hypothetical controller mechanism illustrated in the discussion: by adjusting a valve restricting air flow to and from the reset bellows. Both valves are actuated by rotary knobs with calibrated scales. The reset knob is actually calibrated in units of minutes per repeat, while the proportional band knob is labeled with a scale of arbitrary numbers: The following photograph shows one of the manifold plates removed and turned upside-down for inspection of the air passages: Rotating the plate 90 degrees connects the four air ports together as two different pairs. A more sophisticated field-mounted pneumatic controller is the Foxboro model 43AP, sporting actual PV and SP indicating pointers, plus more precise tuning controls.