How to calibrate electronic type level switch low?
Answer / carl_ellis
Calibrating a point level switch
Contact level switches detect the presence or absence of
the medium, whether solid or liquid, by direct contact with
the medium. The switch output for most devices is an
on/off binary signal that reflects the presence or absence
of the medium. Some level switches use a 4-20mA output
that does not modulate, the current signal is either 4mA or
20mA, depending its detection state.
Most level switches offer some form of sensitivity
adjustment (depends on the technology) and some have an on-
delay or off-delay adjustment of the output relay trip,
used to avoid nuisance trips.
Calibration consists of
- testing whether the switch output changes state when the
presence or absence of the medium is changed and adjusting
the sensitivity setting for the specific medium used with
the switch.
- whether the on-delay and off-delay settings comply with
the requirements of the installed application
Depending on the technology, there might be sensitivity
adjustments or on-delay or off-delay adjustments, which are
specific to the installed application, and a calibration
would cover.
A non-contact level switch, like Siemen ultrasonic ULS200,
can be tested in place by comparing the reading with a
physical distance measurement (tape measurement) or out-of-
process by shooting against a solid target and measuring
the distance to check the trip and reset setpoints.
Carl Ellis
Measure First
Is This Answer Correct ? | 2 Yes | 0 No |
what is the reason for flow fluctuations happen on differential flow transmitter during in service
there is one orifice plate already installed on 3" line, but my previous engineer(who is not working here) removed that tx, but now i want to take it in to the process, so now what i have to do now? flow fluid is hytherm oil of temp. 260deg & pressure is 3bar.
what is intrinscily safe system and where we use?
1)How many tpes of vibration probe and how many tpyes of vibration. 2)how we can calibrate a vibration probe with tk3 3)what is RMS value in vibration measuring application and how we calculate it.
How can SmartPlant Instrumentation users take advantage of these global services?
In closed loop control there are several “blocks” used to show the interactions between the process and the control system. These blocks are referred to as the “process” and the “controller.” Describe the relationship between these two blocks when creating a well tuned control loop.
Calculate the maximum pressure drop that can be allowed to occur across a control valve, so that we can prevent cavitation / flashing from occurring. Use the following formula: Δ P allow = Km (P1 – PvapourA) where, Δ P allow - the maximum allowable differential pressure for sizing purposes, or terminal pressure drop; Km- the valve recovery coefficient from the manufacturer’s catalogue; P1 - absolute inlet fluid pressure; PvapourA - absolute fluid vapour pressure at the inlet temperature; Use Atmospheric pressure = 101.3 kPa, P1 = 1200 kPa(g), PvapourA = 4 kPa, KM = 0.72
can anyone tell free downloads website for fundamentals and principle of basic pressur,temperature,level and flow
We Have Two Field bus Pressure Transmitters of Different Sensor Range (I.E One is of Lower range and Another is of Higher Range).Is same Process Line. My Question is Can i provide Saturation Limit to my field Bus Transmitter as We can provide Saturation current limit to HART Instruments. As During Low Pressure Both Working OK ,But During High Pressure, transmitter with Lower sensor range Goes to Fault mode as Beyond its Sensor Limit it can Measure, So may I provide Saturation point Some where to Suppress This Fault during High Pressure.
Instrumentation symbols interpration, P& ID, Logic diagram analysis, Electrical drawing analysis.
can any one tell leakage class in control valve depend on which parameter and there is any specific table or chart for selection of valve leakage class
why does a transmitter o/o signal starts from 3-15psi or 4- 20mA?