What is Calibration:
Procedure
ISOLATION STEPS
â‘ Close the high
side valve from the manifold
â‘¡ Open the
equalizer valve from the manifold
â‘¢ Close the low
side valve from the manifold
â‘£ Close the equalizer
valve from the manifold
⑤ Be careful do
not open all the three valve in the same time to avoid sensor damage in case of
process high temperature or chemical.
CARIBRATION
â‘ Set up and
connected the related instruments required for the test as shown in fig.
â‘¡ Transmitter without optional elevation/suppression
kit
With no calibrating pressure on
transmitter, adjust zero screw so that output is 4mA.
â‘¢ Transmitter with optional elevation/suppression kit
Apply
calibrating pressure equal to the lower differential limit. Adjust
elevation/suppression screw so
that output is approx. 4MA. Still, adjust zero screws so that the output is exactly
4mA.
â‘£ Apply
calibration pressure equal to upper differential limit. Output should be 20mA.
⑤ If output is not
correct, adjust span screw so that output is 20mA.
â‘¥ Repeat step 3
through 5 until both output are correct.
⑦ If this
transmitter has the output indicator, confirm the indicated value which should
be your LRV value at 4mA and URV at 20mA.
TAKIN IN SERVICE
STEPS
â‘ Open the equalizer
valve from manifold
â‘¡ Open the Low
side valve from manifold
â‘¢ Open high side
valve from manifold
â‘£ Close the
equalizer valve from manifold
⑤ Be careful do
not open all three valve at the same time to avoid sensor damage in case of
process high temperature or chemical.
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