IP Review 2012 Flashcards
(40 cards)
Which actuator is installed on a 4 inch globe valve?
Diaphragm Reciprocating
An electronic weight measuring system uses a linear variable differential transformer (LVDT), output to indicate the weight of the fluid in a filled cam. The supplier has changed the weight of the can, what has to be done to recalibrate the instrument?
Recenter the core in the LVDT
A spring diaphragm actuator has stopped working. On inspection it is found that the yoke and dome is badly corroded with nitric acid. What should be done to correct the problem?
Replace the actuator
On a pneumatic controller the output reading is 5% high through the range. How is this error corrected?
Adjust zero 5% down
A valve is verified to be stroking properly when air is applied directly to the actuator. During calibration an increase in signal to the positioner causes the valve to travel in the opposite direction from what is expected. What is the cause?
Positioner action is incorrect
What maintenance should be done first when a bare capacitance probe transmitter indicates 60% when the actual level is 50%?
Clean the probe
A push down to close plug style valve requires a new actuator to make the system fail closed. Which actuator should be installed?
Diaphragm reverse acting
A large DSC system is experiencing problems as a result of many analog Input/output faults. The analog faults are all linked sequentially to 1 card. Where is the fault source?
The multiplexed AD card
A cellular link has been configured for SCADA communication, there is no communication, What does NOT affect the link?
HMI failure
Which procedure is followed to install a 1/4 compression fitting on a steam line after isolating the process?
Apply approved thread sealant to pipe threads, tighten into pipe connection, fully insert tubing into fitting and tighten 1 1/4 turns past finger tight.
A setpoint is sent out from central control to 3 remote sites. The setpoint is NOT received at any of the remote stations. What is the cause?
The antenna at the central control has failed
A positioner has been calibrated with these as found results 0% input= 10% travel, 50%input = 50% travel, 100% input=90% travel. What is the likely cause of this data?
Span of the positioner is too small
What is the first step to replace a component on a nuclear solids flow meter?
Close shutter and lock-out
A displacer type density measuring system is progressively showing lower and lower densities. What is the most probable cause?
The displacer is becoming heavier
Which method is used to calibrate a toroidal conductivity analyzer?
With a probe connected, loop a wire through the toroid and attach the decade resistance box and dial in desired resistance
In a PLC system it is determined that the processor and associated rack have lost power. To what state would the outputs have defaulted?
low
Where should instruments and equipment be installed in panels to respect ergonomic practices?
Switches at belt level, indicators and recorders at eye level, controllers between belt and eye level, alarm panels at the top
A HMI graphic has been configured to operate two motors. Motor 1 tag is improperly addressed, motor tag is correctly addressed. The status of motor 1 is changed, which error results on the HMI?
Motor 1 graphic does not change animation and motor 1 status does not change
During routine maintenance on a magnetic flow meter, readings are found to be low and slow to respond what is done to prevent this problem?
Remove the flow meter and clean the sensing electrodes
A direct acting control valve with a bench setting of 9-15 psi is installed with a 3-15psi positioner, it is in operating condition. At what positioner input pressure would the valve begin to operate?
3psi
How is a pressure transmitter, rated for -40 degrees C, installed on a water pipeline where ambient temperature can drop below -50 degrees C?
Remotely in insulated and heated enclosure with insulated and heated sensing lines
A MODBUS RTU device is unable to communicate with a MODBUS ASCII device. How is the problem corrected?
Use RS 485
How can the accuracy of a newly replaced pH probe be confirmed?
Check in a buffer solution , install the probe and verify with a grab sample
Which component must be cleaned before calibrating the turbidity analyzer?
The window
