Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

how to calibrate temprature switch and flow switch ?

Answer Posted / carl_ellis

The key to 'calibrating' a temperature switch is it is a
switch, it is not a continuous analog sensor. So there's
no need to mess around with a zero and span value, like you
would on temperature transmitter.

All that matters is setting the switch's trip point, the
setpoint, and in some cases, the reset
(deadband/hysteresis) point. There is no need to mess
around anything but the trip point, it's time consuming
enough to get a precise setpoint on switch.

You need to know
- the setpoint
- in some cases, the reset (deadband/hysteresis) point
values
- whether the setpoint (SP) is for a rising or falling
temperature. Because they're mechanical switches, a SP for
falling is NOT same as a SP for rising.
- switch functionality - Does the switch close or open on
rise or fall. There are applications for all the
variations: close on rise, close on fall, open on rise,
open on fall.

Check how to change the setpoint on the switch. Some
switches have a setpoint lock (nut). Some are blind
adjustments, some are adjustments with indicated
temperature values. Some have a separate
deadband/hysteresis adjustment. The latest temperature
switches are digital, and the setpoint and hysteresis reset
point are entered as values.

Many procedures require an actual test with a calibrating
heat/cold (dry block calibrator or oil bath) source and a
temperature "standard" is needed for a reference
temperature, to prove the mechanical setting is correct.
Sometimes the standard is a certified dry block with a
readout, sometimes it's a mercury thermometer, sometimes
its certified RTD with a certified readout. Older cal
equipment has stand-alone electrical equipment, like an
indicator lamp or an ohmmeter that is used to indicate
switch closure on the temp switch, more modern cal
equipment has built-in connections and an indicator for
that.

Make the setpoint adjustment, run the temperature source,
heat or cool, and note the trip and reset points. If
needed, make adjustments and re-run the test until the
setpoint (and reset point) are within the spec needed.

Record the results, put a cal sticker or tag on the beast,
and you're on to the next one.

Tell 'em Carl sent you.

Is This Answer Correct ?    8 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is heating effect?

2341


WHY THE DEGREE OF VALVE PLUG AND VALVE SEAT IS SLIGTLY DIFFERENT I CONTROL VALVE TRIM DESIGN

1982


How to work togather like sov,limit switch,proxy switch and booster in xv

4212


How does work A temperature valve or fv control valve in process plz brief me

2437


hiii.... can any one provide me previous years question paper of hindustan petroleum for instrumentation engineering???

1977


What are different types of cable?

1087


What is the use of GMV in turbine?

4416


How to Calibrate Radar Level Transmitter in Field

1237


what can of fault ofently come in vibration mesurement?

2134


How to calibration a control valve?

1159


i want to find out iffco get test paper

13092


Explain why use mmwc unit?

1038


how to calibrate mass flow meter (Coriolis)? Example calibration range: 0 to 2500 kg/hr line size 3" fluid: Etheline glycol (MEG)

2677


how to check earthing,what is minum ohms for proper earthing

1938


what is the minimum power (P=VI)to produce a spark?

1974