Growler Operation?

It may be another example of US and UK slang being different! Thanks for making me howl Louis and hopefully someone more grown up can help you.

If I recall correctly, it simply applies an AC magneitc field to the armature being tested. This induces voltages in the windings and if any windings are shorted, there will be currents flowing and the corresponding forces make the armature vibrate or "growl". it's been a long time so don't take this as gospel.

-- Don Kelly snipped-for-privacy@peeshaw.ca remove the urine to answer

It seems to me you also had to pass a hack saw blade over the armature to find the shorted winding.

Jay

In article , snipped-for-privacy@peeshaw.ca says... | If I recall correctly, it simply applies an AC magneitc field to the | armature being tested. This induces voltages in the windings and if any | windings are shorted, there will be currents flowing and the corresponding | forces make the armature vibrate or "growl". | it's been a long time so don't take this as gospel. | -- | |

Now you have reminded me, I can confirm your description is accurate. I only had a brief introduction to one, at which time it was called a 'growler' here in the UK.

I remember it as cast alloy casing forming the base, with large opening shaped like a V at the top. The suspect armature is lowered into the V and rotated slowly round. The example I saw probably dated from the

1940's and was designed for checking electric drill, vacuum cleaners and similar armatures.

In article , snipped-for-privacy@wideopenwest.com says... | t seems to me you also had to pass a hack saw blade over the armature to | find the shorted winding. | | |

I might be wrong, but I think the hacksaw blade was used to short across segments of the armature.

Once you had found a faulty armature, I believe you then worked your way around the commutator one segment at a time shorting them, whilst listening for a change of 'growl' note. The one which was already shorted, would produce no change in the note.

Thanks to all who provided data, and URLs.

My wife (who has no technical expertise) asked what a Growler was, and why I needed the information. She then suggested I use the browser search function for info. I explained I had, but the search had produced info about music groups, and other info of no interest to me. She then asked what it tested. She suggested including that in the search string. "Armature Growler" produced quite a large number of hits.

I guess a clear thinking logical mind wins over a technical one, at least in this case.

Some of the links indicated that instrumentation used by motor shops today have all but eliminated the need for devices such as the growler.

Can any motor shop people, or other enlightened individuals explain what instrumentation they were referring to?

Thank you.

Louis--

********************************************* Remove the fish in address to respond

Generally motor shops induce a magnetic field in the rotor and wrap it with magnetic sensitive paper. The pattern on the paper shows if you have problems. It's more sensitive than a growler.

in article KP16b.6412$ snipped-for-privacy@twister.nyroc.rr.com, jim at snipped-for-privacy@address.net wrote on 9/5/03 8:19 AM:

What is such paper? Where can you get it?

Bill