Interesting results with a calibration test on flow meters - HELP
Interesting results with a calibration test on flow meters - HELP
(OP)
I'm currently gauging and calibrating two flow meters for an experiment later on. And am having some interesting results.
I have attached a picture to show you my current set up.
Why am I doing this? I have them hooked up directly inline to make sure that they are getting accurate and repeatable results.
The meters themselves are ER-500's from Badger Meter. The rotors attached to the meters are a oval gear setup with a 1/4" NPT tap on either side. I have a pump that is hooked directly up to the rotors. I have ran a test on the meters 6 separate times and let the pump run for a few minutes to stabilize. And each time the Right Meter inline always has a higher readout of GPM. Why would this be? I would think that the first meter would have the larger readout due to that being the first one affected by the pressure from the pump. Could it be a hardware issue? Pump Issue? Rotor Issue?
My results from tests are as follows (All answers in GPM):
Test# 1:
Test #2:
Test #3:
Test #4:
Test #5:
Test #6:
Sorry for the formatting, wrighting this hastily before I leave the office for the day. I might need an adult beverage. Also the Red Wings play tonight, that'll cheer me up.
Thanks for all your help in advance!
I have attached a picture to show you my current set up.
Why am I doing this? I have them hooked up directly inline to make sure that they are getting accurate and repeatable results.
The meters themselves are ER-500's from Badger Meter. The rotors attached to the meters are a oval gear setup with a 1/4" NPT tap on either side. I have a pump that is hooked directly up to the rotors. I have ran a test on the meters 6 separate times and let the pump run for a few minutes to stabilize. And each time the Right Meter inline always has a higher readout of GPM. Why would this be? I would think that the first meter would have the larger readout due to that being the first one affected by the pressure from the pump. Could it be a hardware issue? Pump Issue? Rotor Issue?
My results from tests are as follows (All answers in GPM):
Test# 1:
Left Meter: 2.93
Right Meter: 3.54
Test #2:
Left Meter: 3.70
Right Meter: 3.85
Test #3:
Left Meter: 3.53
Right Meter: 3.80
Test #4:
Left Meter: 3.18
Right Meter: 3.67
Test #5:
Left Meter: 3.22
Right Meter: 3.68
Test #6:
Left Meter: 3.37
Right Meter: 3.75
Sorry for the formatting, wrighting this hastily before I leave the office for the day. I might need an adult beverage. Also the Red Wings play tonight, that'll cheer me up.
Thanks for all your help in advance!
The joy of engineering is to find a straight line on a double logarithmic diagram.





RE: Interesting results with a calibration test on flow meters - HELP
RE: Interesting results with a calibration test on flow meters - HELP
Swap meters in the first instance.
Check setup in the readers
Keep records.
Check wires. That wiring looks a bit dubious and very thin wires. You can get broken wires very easily which gives random errors.
Lots of error checking to do.....
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Interesting results with a calibration test on flow meters - HELP
RE: Interesting results with a calibration test on flow meters - HELP
Your unspecified model of oval gear flowmeters appear to have the red Badger logo.
The current Badger spec sheet shows the max flow rate for a 1/4" oval gear flow meter to be 2.2 GPM,
yet you're pushing over 3 GPM through them.
Badger's manual does not specifically advise against over running its max flow rate nor does it warn against pressure drops exceeding 1 bar, but a lot other oval gear brands do.
You need a flow meter with a higher capacity flow rating.
RE: Interesting results with a calibration test on flow meters - HELP
Accuracy is only valid when you are operating within the devices flow range.