『FM500 Flow Meter Manual: Calibrating Ultrasonic Transit-Time Instruments for Clean Commercial Fluids』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
FM500 Flow Meter Manual: Calibrating Ultrasonic Transit-Time Instruments for Clean Commercial Fluids
Quick Answer: Calibrate an FM500 transit-time ultrasonic flow meter by first checking pipe dimensions, sensor spacing, fluid type, and zero flow. Then verify the meter against a traceable reference flowmeter. For clean commercial fluids, adjust the calibration factor only after the signal strength and sound speed are stable.
Calibrate an FM500 when you install it on a new pipe, change sensors, change fluid, or after any pipeline cleaning or shutdown. We have seen customer sites where a 2 percent error appeared after a filter change on a 150 mm cooling water line in Malaysia. The fault was not always the meter. Air pockets and a small shift in pipe wall travel time caused the error. Calibration should also be checked every 12 months on clean commercial fluids.
What You Need Before Starting Calibration
You need the actual pipe outer diameter, wall thickness, pipe material, liner material, and fluid type. For a DN100 carbon steel pipe with 5 mm wall and clean water at 25 °C, enter these values exactly into the FM500 transmitter. Do not use nominal pipe size as the outer diameter. A 100 mm schedule 40 pipe has an outer diameter of 114.3 mm. That small difference changes the path length and the flow reading. Also collect the operating temperature, pressure, and expected flow range.
FM500 Zero Calibration for Clean Commercial Fluids
Fill the pipe with the clean fluid and stop all pumps. Wait until the fluid is completely still. On the FM500 transmitter, open the zero calibration menu and let the meter average 60 seconds. A good zero reading on a DN80 water line stays within plus or minus 0.01 m/s. If the zero value drifts, check for valve leakage, trapped air, or pump bypass flow. Most engineers skip this step because the pipe looks static. We do not skip it. A zero shift of 0.03 m/s on a 50 mm line produces a visible error at low flow.
Flow Calibration Check with a Reference Meter
Mount a calibrated portable transit-time meter on the same clean fluid line. Run the process at three flow rates. Use 10 percent, 50 percent, and 90 percent of the normal flow range if the process allows. For a water transfer line in Indonesia running at 85 m³/h on DN150, we compared both meters for 15 minutes at each flow. The FM500 read within 0.8 percent of the reference meter. If the error is larger than 1 percent, do not adjust the meter immediately. First clean the pipe surface, apply fresh coupling compound, and check the sensor cables.
Parameter Settings That Affect Calibration
Sound speed is the fastest diagnostic for clean commercial fluids. For water at 20 °C, the FM500 should show around 1480 m/s. For 20 percent ethylene glycol, expect about 1660 m/s. A wrong value means the fluid type, temperature, or
Calibration Records and Typical Intervals
Keep a calibration log for each FM500 meter. Record the date, fluid, temperature, pipe size, zero value, signal strength, sound speed, and any offset. For clean commercial fluids with stable temperature and no solids, a 12 month field verification is enough. For billing or custody transfer, use a third-party flow laboratory every 24 months. A chemical plant in Vietnam reduced rework after adding these records to the shift handover sheet.
How to Get a Firm Quote for an FM500 Meter and Calibration Service
Send your pipe size (DN), pipe material, wall thickness, fluid type, temperature, pressure, and flow range to Silver Automation Instruments. Also state whether you need the FM500 wall mount or portable version, 4-20 mA HART, RS485 Modbus, or pulse output. A technical sales engineer will reply with a calibration sheet, lead time, and price for your country. Phone: +86-25-68650347. WhatsApp: +86-25-52155837. WeChat: +86 15365082610.
FAQ: FM500 Ultrasonic Flow Meter Calibration
What type of fluid works with the FM500 transit-time meter? Clean commercial fluids such as water, demineralized water, glycol, light oils, and liquid chemicals with low solids and no large free gas bubbles. Fluids with more than 1 percent solids or heavy slurries often need a Doppler meter instead.
How often should I calibrate an FM500 flow meter? Check zero and signal every 12 months on clean fluid. If you use the meter for billing, run a reference meter check at least once per year and a laboratory calibration every 24 months.
Can I calibrate the FM500 without a reference flow meter? You can perform a zero calibration and a parameter check without a reference meter. For a true flow verification, you need a traceable reference meter or a known volume and a timer. A simple bucket test on a small pipe can catch gross errors.
Why does the FM500 show a flow reading when the pipe is full and the pump is off? That reading is usually a zero offset from trapped air, valve leakage, or a damaged sensor cable. Run the zero calibration again after bleeding air and closing isolation valves.
What information is needed for a quote for an FM500 flow meter? Pipe size (DN15 to DN1200), material, wall thickness, fluid type, temperature, pressure, flow range, and output requirement. Send those values to Silver Automation Instruments on WhatsApp +86-25-52155837 or call +86-25-68650347.
Hot News
Related AD
