where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

653 views
Technical Discussions
Massimiliano Pau
Teacher, -
Univ. of Cagliari, Dept. of Mechanical Engineering, Italy, Joined Sep 2002, 25

Massimiliano Pau

Teacher, -
Univ. of Cagliari, Dept. of Mechanical Engineering,
Italy,
Joined Sep 2002
25
08:22 Jan-17-2002
Problems with electromagnetic fields

Dear friends

I'm carrying out some UT immersion test on a aluminium wheel driven by an electric motor.

Unfortunately the signal is very disturbed by "spikes" generated by the motor. Any suggestion in order to reduce (or eliminate) this problem?

Thanks in advance

Massimiliano Pau


 
 Reply 
 
Joe Buckley
Consultant, ASNT L-III, Honorary Secretary of BINDT
Level X NDT, BINDT, United Kingdom, Joined Oct 1999, 528

Joe Buckley

Consultant, ASNT L-III, Honorary Secretary of BINDT
Level X NDT, BINDT,
United Kingdom,
Joined Oct 1999
528
00:42 Jan-17-2002
Re: Problems with electromagnetic fields
Simple things to try

1. Move or Shield the power to the motor - make sure the motor wires are not less than 10cm from the probe connections. Check grounding etc. - Thry linking the probe body to the motor case. If its already joined try disconnecting it (These things are seldom rational until you've solved them)

2. Put some capacitors across the motor contacts - 0.1 uF low impedance type should reduce most spikes. Wrap the power leads round a toroid or use series inductors

3. Move the motor - Drive the mechanism via a belt and pulleys (Usually necessary anyway to keep the motor out of the water)

4. Make Sure the motor power supply is not contributing - Some switched mode power supplies can kick out a lot of noise.- Do you get spikes when the voltage is reduced and the motor not turning? If so its not the motor...

Good luck

Joe


4. If all else fails use an AC shaded pole motor or similar -


: Dear friends
.
: I'm carrying out some UT immersion test on a aluminium wheel driven by an electric motor.
.
: Unfortunately the signal is very disturbed by "spikes" generated by the motor. Any suggestion in order to reduce (or eliminate) this problem?
.
: Thanks in advance
.
: Massimiliano Pau
.



 
 Reply 
 

Product Spotlight

Compact NDT inspection-heads for measurements with active thermography

The compact inspection head is suitable for thermographic ndt tasks. The uncooled infrared camera
...
is specially developed for NDI-tasks and offers a thermal sensitivity until now known only from thermal imagers with cooled detector. All required components and functions are integrated into the inspection-head. You will only need an ethernet cable to connect the sensor with the evaluation system.
>

HARDNESS TESTER TKM-459CE combi

TKM-459CE combi applies 2 methods of hardness control: UCI and Leeb. It provides high-accuracy tes
...
ting of metals and alloys as well as items of different sizes and configurations, their hardened layers and galvanic coatings. Device represents results in HB, HRC, HV and others. Shock-, dust- and water-proof housing with intuitive software make this gauge easy to use in all working conditions.
>

OPBOX with standard software is able to do all types of inspections and measurements: flaw detection in welds and materials, scanning of objects, testing composite materials, forged and moulded pieces, many UT inspections, measurements of properties of ma

Typical applications: UT measurements with pulse technique, Measurement of thicknesses also at hig
...
h temperatures, Measurements of properties of materials, including fluids and gases We are delivering a standard version of the software (for any Microsoft Windows up to 10 x64 with Microsoft Hardware certification report Approved) and for special needs: SDK with ready to use examples for LabView, MATLAB x64, C++ wrapper for dll, Python and Linux., and also low-level description of how to control our devices directly from any USB tools
>

Ultrasonic Squirter/Gantry System

TecScan’s NDT Ultrasonic Gantry Systems are industrial Squirter scanners designed for non-destru
...
ctive quality testing and raster scanning of large structures and parts. The Gantry Systems are usually composed of an Industrial Mechanical Scanner and a Control Room with System Workstation.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window