Do you need to change the range of an existing orifice (d/p) flow meter? You do not need to gather a bunch of process data and break out your old slide ruler for this one. You only need to know the existing meter’s flow range and d/p range. Enter those two values and your desired flow range into my Orifice Meter Range Changer and it will tell you what to calibrate your orifice (d/p) meter to.
Example
You have a d/p transmitter calibrated to 0 – 100 inches of water connected to an indicator with a range of 0 – 25 gallons per minute (GPM). The indicator occasionally reads full scale, so you want to change its range to 0 – 30 GPM. What do you calibrate the d/p transmitter to?
You calibrate your d/p transmitter to 0 – 144 inches of water to achieve a flow range of 0 – 30 GPM.
What if 30 GPM is not high enough? What is the maximum flow range you can achieve without changing the orifice? Your d/p transmitter has a maximum range of 0 – 250 inches of water, so enter 250 into New d/p Range field.
You can calibrate your flow range to 0 – 39.5 without changing the orifice.
I put a link to Orifice Meter Range Changer over there on the left, right under my orifice bore calculators.