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 -

Hillger NDT GmbH
was founded in 1984 and develops special ultrasonic imaging systems for high-tech materials.
388 views
Technical Discussions
Kelly Schauf
Kelly Schauf
08:13 Aug-18-1998
Non destructive isolation of PC-mount Transformer short

To the forum:

Currently, I am testing a printed-circuit-board-mount transformer.
There is one primary winding and three secondary windings.
There are two powdered-iron 'E' cores that are epoxied
together around the bobbin to provide the core for the transformer.

I have a problem where the inductance and the Q of the primary coil
drop way below normal past 1500 Hz with a signal of 100millivolts AC
applied. I suspect that there is a shorted turn of wire that may be causing
this.

Generally, there is maybe 1000+ turns of wire on the transformer, and the
chances of finding a marginal short-circuit with merely a microscope and
the eyes is a 'needle-in-a-haystack' type of chance. Is there some
method that would incorporate an electrical signal that would enable me
to find a short-circuit in the primary winding?

Any and all ideas are welcome. Questions are also welcome.

Regards,

Kelly Schauf


 
 Reply 
 
Jeff Nelson
Jeff Nelson
07:44 Jun-28-2000
Re: Non destructive isolation of PC-mount Transformer short
r this may help you locate how far down the line the short is.



 
 Reply 
 
Jamie Gauthier
Jamie Gauthier
09:33 Jul-01-2000
Re: Non destructive isolation of PC-mount Transformer short
In response to the TDR message post. Time Domain Reflectometer works well
but has several disadvantages. The instrument works well as long as you
have the mininum length of cable to measure. TDR's have a dead zone. This
dead zone can range from 25 to 50 feet (plus or minus depending on the
quality of your instrument.) Do you have another transformer with an equal
number of turns? If so then you can reference the value of one against the
other using a TDR. The TDR I have been using lately has an error of + or -
1% of the total length of the cable. When you are dealing with transformers
this is very large and usually unaccpetable. Once you find the short then
what? Are you equipped to hand wind it? Good luck with you
trouble-shooting. Regards,


Jamie Gauthier
Field Service Electronics Technician
Toll Free: 800-661-0066
Fax: 780-440-2538
Cell: 780-940-3427
Pager: 780-431-7470
E-mail: jgauthier@rtdquality.com
Web Site: www.rtdquality.com


--------------------
: To the forum:

: Currently, I am testing a printed-circuit-board-mount transformer.
: There is one primary winding and three secondary windings.
: There are two powdered-iron 'E' cores that are epoxied
: together around the bobbin to provide the core for the transformer.

: I have a problem where the inductance and the Q of the primary coil
: drop way below normal past 1500 Hz with a signal of 100millivolts AC
: applied. I suspect that there is a shorted turn of wire that may be causing
: this.

: Generally, there is maybe 1000+ turns of wire on the transformer, and the
: chances of finding a marginal short-circuit with merely a microscope and
: the eyes is a 'needle-in-a-haystack' type of chance. Is there some
: method that would incorporate an electrical signal that would enable me
: to find a short-circuit in the primary winding?

: Any and all ideas are welcome. Questions are also welcome.

: Regards,

: Kelly Schauf




 
 Reply 
 

Product Spotlight

Research and Applications Development For NDT

The Research and Applications Development (RAD) group is a newly formed team within Acuren dedicat
...
ed to tackling challenging inspection problems. Our focus is the development of novel, field deployable, advanced inspection techniques for use in cases where standard NDT methods are ineffective. We don't wait for new innovations, we engineer them. From concept to commissioning.
>

Aerospace Systems - Automated Ultrasonic Inspection

USL are specialists in the design and manufacture of turnkey ultrasonic inspection systems for aer
...
ospace applications. From monolithic composites to complex honeycomb structures. This video shows just a few examples of what is possible, find out more at: www.ultrasonic-sciences.co.uk
>

NEW - TD Focus-ScanRX

The NEW Next Generation Advanced UT platform, TD Focus ScanRX - Also available as a card stack solut
...
ion. Key Improvements 1. Data acquisition is significantly faster than current design 2. Better aesthetic – closely aligns with HandyScan RX 3. Improved IP rating (Target IP66) 4. Ruggedized housing 5. Connectors are protected from impact and ingress 6. Integrated stand and separate retractable handle easy to keep clean) 7. Touchscreen with ruggedized display glass 8. 3-Axis encoder input
>

Surf-X® Array Probe

Introducing the Surf-X family of flexible Eddy Current Array (ECA) probes. Featuring unique multiple
...
coil sets and proprietary X-PROBE technology, Surf-X array probes can quickly and accurately handle a range of inspection applications, from inspecting corrosion or cracking in pipes, pressure vessels, or tanks, to assessing and sizing cracks in raised welds and friction stir welds.
>

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