Term
Process Measurement/Control Terminology
Process Disturbance |
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Definition
| Conditions that cause a process variable to vary from its desired value |
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Term
Process Measurement/Control Terminology
Process |
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Definition
| Operation or operations of used in the treatment of materials |
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Term
Process Measurement/Control Terminology
Process Variable |
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Definition
| A quantity whose variation indicates a change in the operation of the process |
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Term
Process Measurement/Control Terminology
Steady State |
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Definition
| Input Varibale equals output variable |
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Term
Process Measurement/Control Terminology
Setpoint |
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Definition
| The desired value of the process variable |
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Term
Process Measurement/Control Terminology
Manipulated varibale |
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Definition
| The process variable regulated by the control loop |
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Term
Process Measurement/Control Terminology
Controlled variable |
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Definition
| The process variable selected to be maintained between certain limits |
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Term
What is the Range of this pressure gauge?
What is the span of this pressure gauge?
Lower Range Value?
Upper range value?[image] |
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Definition
The range of this pressure gauge is -100 kPa to 500 kPa
The span of this pressure gauge is 600 kPa
LRV is -100 kPa
URV is 500 kPa |
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Term
Instrument Specific Terminology
Accuracy |
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Definition
| the degree to which the output of the instrument approaches an accepted or true standard |
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Term
Instrument Specific Terminology
Resolution |
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Definition
| The smallest interval between two adjacent descrete details that can be distinguished form one another |
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Term
Instrument Specific Terminology
Sensitivity |
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Definition
| The ratio of a change in output magnitude to a change of the input that causes it |
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Term
Instrument Specific Terminology
Dead Band |
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Definition
| The range through which the input of a device can be varied without causing and observable repsonce |
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Term
Instrument Specific Terminology
Hystereisis |
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Definition
| The phenomena of when an instrument is pumped up and the values on the upscale are different than the values on the downscale |
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Term
Instrument Specific Terminology
Linearity |
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Definition
| The closeness to which a curve approximates to a straight line |
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Term
Instrument Specific Terminology
Confromity |
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Definition
| The closeness to which the output curve approximates to a specified curve |
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Term
| What is the definition of pressure as expressed in classical physics |
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Definition
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Term
| State the condtitions that can cause damage to pressure instruments |
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Definition
Improperly returning gauges to service
Temperature extremes
Excessive vibration
Overpressurization |
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Term
| What are the basic units of fluid flow |
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Definition
LBM/Hr- pound mass/hour
LBM/Min- pound mass/min
GPH- gallons per hour
GPM- Gallsons per minute |
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Term
| What is the definintion of temperature |
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Definition
| The average kinetic molecular motion of the atoms within a substance |
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Term
| What is the definition of heat |
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Definition
| thermal energy of a substance |
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Term
| What are the three methods of heat transfer |
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Definition
Conduction
Convection
Radiation |
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Term
| What are the two flow meter classifications |
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Definition
Restricting element
Displacement element |
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Term
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Definition
this is the magnitude by which the controlled variable 'swings'
past the setpoint. 5/10% overshoot is normally acceptable for most loops. |
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Term
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Definition
the time it takes for the process output to achieve the new
desired value. One-third the dominant process time constant would be
typical. |
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Term
Tuning Verbage:
Decay Ratio |
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Definition
this is the ratio of the maximum amplitude of successive
oscillations. |
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Term
Tuning Verbage:
Settling Time |
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Definition
the time it takes for the process output to die to between,
say +/- 5% of setpoint |
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