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15 

Troubleshooting

Troubleshooting

If you run into trouble with installation or operation, get in touch with support (

page 2

).

General Use

  Issue: 

My device does not turn on or has trouble staying on.

 Action: 

Check power and ground connections (

page 6

).  Please reference the technical 

specifications to ensure you have the proper power for your model.

  Issue: 

The analog output signal indicates values lower than expected.

 Action: 

Analog signal voltage degrades over long distances. You can minimize this effect 

by using wires with a heavier gauge, especially in the ground wire.

  Issue: 

How often do I need to calibrate my device?

 Action: 

Annual recalibration is recommended. Check your device’s last calibration date. If it 

is time to recalibrate, request a recalibration from customer support (

page 2

).

  Issue: 

I dropped my device. Is it OK? Do I need to recalibrate?

 Action: 

If the device powers up and appears to respond normally, then it is likely OK. 

It may or may not need a recalibration. Tare the device, and compare it against 

a known-good flow standard. If it checks out, keep using the device, but tell us 

about the drop at your next annual recalibration so we can check it out for you.

Flow Readings

  Issue: 

The live flow readings won’t settle down.

 Action: 

The device is very fast, so it can detect subtle variations in flow that may go 

unnoticed by your other devices. This sensitivity can help detect problems with 

pumps or flow controllers. You can lessen this sensitivity by increasing the flow 

averaging.

 

Controllers use PD or PD²I control loop algorithms to reach the setpoint 

given. These parameters are adjustable in the field. 

  Issue: 

My controller won’t reach its setpoint.

Action

: The flow rate is related linearly to the pressure drop across the device. If there 

isn’t enough of a pressure difference between the inlet and outlet, the controller 

may not be able to reach setpoint. Often, increasing the inlet pressure will fix this 

issue.  If increasing the pressure doesn’t help, check to see if there is a clog. Teflon 

tape can often get stuck in the flow channel and block flow. Make sure to clean 

out any loose Teflon tape and never tape the first two threads entering the device 

to help avoid this issue.

  Issue: 

My flow readings are negative.

 Action: 

Under conditions of no flow, a negative flow reading can indicate a poor tare. Set 

a zero setpoint and see if the flow returns to 0 after 2 seconds.

  Issue: 

Does the controller work if it is laying down? Will it be accurate?

Action

: Yes to both. The flow controller is internally compensated for any changes in 

orientation and can be used sideways, on its back, or upside-down.

  Issue: 

Can I put the flow controller on top of a vibrating device? Will it be accurate?

 Action: 

Yes you can. However, sensor noise will increase if the flow controller is vibrating.

  Issue: 

My controller does not agree with another mass flow meter I have in line.

 Action: 

Check the STP or NTP settings to ensure that your standardized temperature and 

pressure references match those of your other flow calibrator. Also check that the 

correct gas is selected (

page 18

).

Содержание ALICAT IM

Страница 1: ...OPERATING MANUAL FOR MASS FLOW DEVICES Models IM and IMC...

Страница 2: ...a 91 022 41248010 Recalibrate your mass flow controller every year Annual calibration is necessary to ensure the continued accuracy of readings and to extend the Limited Lifetime Warranty Fill out the...

Страница 3: ...tor valve position to maintain your process and identify failures before they occur This manual covers the following instruments IMC Series gas mass flow controllers IM Series gas mass flow meters For...

Страница 4: ...9 Data Format 10 Changing the Setpoint 10 Totalizer 11 Batch Dispensing 11 Changing the Gas 11 Control Loop 11 Command Quick Reference 12 Advanced ASCII Commands 12 Modbus RTU 13 Communicating Via Mo...

Страница 5: ...r overrange etc Mounting The flow controller can be mounted in any position including upside down Mount the device so that flow passes through the flow body in the direction shown by the flow arrow Th...

Страница 6: ...usly to both sides of the instrument without causing damage Warning Using the flow controller above the maximum specified common pressure will permanently damage the internal pressure sensors If the l...

Страница 7: ...s 4 Analog Setpoint Input meters Ground to tare 5 Tx or A Sends RS 232 Tx or RS 485 A signals 6 Analog Signal Output 0 5 Vdc output signal 7 Power in Powers the device 8 Ground Common ground for power...

Страница 8: ...tuning to adjust response speed and stability for some applications Establishing Communication To connect your device to FlowVision 2 0 1 Download FlowVision 2 0 from alicat com flowvision and instal...

Страница 9: ...unit id command unit_id desired_id Taring the Device Taring gives the device a zero reference for flow measurements ensuring that the device provides its most accurate measurements It is recommended t...

Страница 10: ...dable If the device does not receive a valid command it will ignore it If in doubt hit and start again The default streaming interval is 50 ms This can be increased by changing Register 91 while the d...

Страница 11: ...use the reset totalizer command unit_idT Additional Totalizer functions and options are available in the Serial Primer manual alicat com manuals Batch Dispensing For controllers batch dispensing flow...

Страница 12: ...se a different gas unit_idGgas_number Note For more information on our serial communication commands please see the Serial Primer at alicat com manuals Advanced ASCII Commands The command set on IM de...

Страница 13: ...nts are written to 1003 and 1004 The command arguments are variables that influence how the commands modify the device Analog Signals Alternative to the digital communications described above the devi...

Страница 14: ...ranges that start at 0 Vdc a no flow condition is output at approximately 0 010 Vdc The full scale of the device is output by the top of the range 5 Vdc for 0 5 Vdc 10 Vdc for 0 10 Vdc or 20 mA for 4...

Страница 15: ...lessen this sensitivity by increasing the flow averaging Controllers use PD or PD I control loop algorithms to reach the setpoint given These parameters are adjustable in the field Issue My controlle...

Страница 16: ...ility page 2 Serial Communications Issue I can t communicate with the device when it is connected to my PC Action 1 Make sure the baud rate your software and COM port required is the one your flow con...

Страница 17: ...erial has entered your device do not take apart the flow body to clean it as this will negate its NIST traceable calibration Please contact support for cleaning page 2 Recalibration The recommended pe...

Страница 18: ...oxide 5 C2H6 Ethane 6 H2 Hydrogen 7 He Helium 8 N2 Nitrogen 9 N2O Nitrous Oxide 10 Ne Neon 11 O2 Oxygen 12 C3H8 Propane 13 nC4H10 Normal Butane 14 C2H2 Acetylene 15 C2H4 Ethylene Ethene 16 iC4H10 Isob...

Страница 19: ...h Liter per hour US GPM US gallon per minute US GPH US gallon per hour CCS SCCS NCCS Cubic centimeter per second CCM SCCM NCCM Cubic centimeter per minute cm3 h Scm3 h Ncm3 h Cubic centimeter per hour...

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