Yeah... the potential for grievous personal injury is quite high when probing spinning/reciprocating/potentially live areas of a machine; especially things with great potential for harm like a spinning PTO yoke.
That half a meter of poly hose provides more than just convenience; it allows you to see what you're probing while you're probing it. Sure if you need to double-check something you think you hear and you don't have your toolbox... I've done it (the long screwdriver, ratchet extension, etc trick) m'self more times than I can count. But I still prefer to use the correct tool. I mean, we're talking $5-8 here, and the diaphragm makes it a much more sensitive diag too as well.
mnem
that said at least. And yet nobody seems to have arrived in our time where a device like a Fluke 805 or a CMAS 100-SL from SKF can give you much more precise and reliable information. Instruments for bearing diagnosis are around since the 60s of the last century, I think.
Oh, there are some evolutions that aren't too bad. At the dealership we had a portable headphone/amplifier box with like a dozen little microphones for diag-ing random suspension noise; we had ones with straps, magnets & screw tabs to sense both ambient and conducted noise. By switching between the microphones you could pretty quickly isolate whether it was a ball joint or a swingarm bushing or a strut bearing, etc. It was also useful for diag-ing axle hub vs carrier bearing noise without having to stick your head in there with a axle/hub/brakedisc spinning at highway speeds.
Sounds so simple... and actually, it is. Sometimes simple is better, like a dim bulb tester.
mnem
*toddling off to ded*
This pump we rebuilt a few weeks back finally used in anger and a little squirt to ~400rpm which is higher than we've been running it displayed it could also be used for water cannon duties !
Mother can it shift some water !
2" delivery doesn't do this thing justice so we're on the lookout for some 2 1/2" or 3"
Some initial runup checks found a slight Timken bearing cycling growl was totally silenced with a tiny bit more bearing preload.
woah! I would skip the 2 1/2" and go to at least 3"....
Yep pretty impressive considering it wasn't even running balls out !
However that was just a shot for you chaps and I wanted to see for myself it given a bit of a squirt
and certainly the 2" Camlock coupler is holding her back.
It's a 80x65mm 2m
3/minute rated pump and yes 2" pipe for the long run we are shifting water to a 40mm line of 8 K pod sprinklers is inadequate and we can only run the tractor to ~1200rpm however Larry minor (our younger larrikin
) now has designs on a traveling irrigator due to the amount of water this pump can shift and an upgrade of the delivery line.
Like TE it never ends !
I've read in numerous places that the absolute value of the cap isn't important just it's rating.
Bah, trawling through the wholesalers sites looking for RIFA replacements, hard to find a single supplier for all the values I want.
I'm thinking to use some Y caps instead of X caps for some values, should be ok, right?
Value isn’t that important. Class is.
Bitsbox sell reasonable replacements
https://www.bitsbox.co.uk/index.php?main_page=index&cPath=65_81
Yes I know class matters, but given Y class have a higher voltage rating than X, it would seem a reasonable substitution.
I'd also argue the value does matter; why have different values otherwise? I'm guessing it's picked based on the power, power factor and likely RFI generated by the PSU's switching frequency (for a switcher) and perhaps how that changes under load.
The Texio CS-4125A uses custom Hybrid IC's as far as I know, so if it fails, it may be a difficult scope to repair. I would recommend trying to get a secondhand HAMEG as they were mostly made from off the shelf parts and can be found for relatively low prices.
McBryce.
I am in Jordan, no Hameg or any other brand available. Check opensooq jordan and see for yourself. If I was in USA, I would have searched through ebay to get the Hameg and other brands for sure.
Hi,
That is a good quality, medium complexity 20MHz 'scope of fairly late design for a CRT type. It will be fine for power supply work, also audio and lowerspeed micrcontroller work. I would take it over a Hantek "20MHz" USB any day. It was sold under the Kenwood name in NA ad UK. $105 is a fair price, they were $700 new not that long ago.
Where in Jordan are you? I spent some time there in '96 & '97
I told the seller that I will take it. Actually, even if it is a bad scope... still the ONLY option available for now. Good to hear that it was a good one. Condition is perfect too.
I live in Irbid and work in Ghor Al-Safi in south, near Karak. You used to work here? good to hear someone knows we exist
Hi,
I was further south. We were running the Thrust SSC car on the Al-Jafra desert. Nearest town was Ma'an. We stayed at the King Feisal bin Abdul Aziz Air Base. Visited Amman a few times but never got as far north as Irbid. I had a short stay at the Queen Alia hospital following an accident with a pneumatic antenna mast . The treatment I received there was first class.
Say, is treatment at QAMH a mandatory thing when working in Jordan or are the nurses THAT pretty? Guy I know who worked with KADB had a stay there after he fell off a vehicle!
Don't know, I was the only one on our team. I got flown in by Puma an had nothing with me. The nurses kept waking me up every couple of hours and asking questions like my age (35) and was I married (no). This appeared to be a source of amusement. They were not doing it for giggles though, just checking for any delayed effects of the accident or drugs. The matron (or what ever they call her) did her rounds in the morning and told me off for being in a theater gown in bed. I manged to explain, and was promptly issed a pair of striped PJs.
Yeah... the potential for grievous personal injury is quite high when probing spinning/reciprocating/potentially live areas of a machine; especially things with great potential for harm like a spinning PTO yoke.
That half a meter of poly hose provides more than just convenience; it allows you to see what you're probing while you're probing it. Sure if you need to double-check something you think you hear and you don't have your toolbox... I've done it m'self more times than I can count. But I still prefer to use the correct tool. I mean, we're talking $5-8 here, and the diaphragm makes it a much more sensitive diag too as well.
mnem
that said at least. And yet nobody seems to have arrived in our time where a device like a Fluke 805 or a CMAS 100-SL from SKF can give you much more precise and reliable information. Instruments for bearing diagnosis are around since the 60s of the last century, I think.
I have to disagree, and get back on TEA. I have several Pico Technology products including one of their automotive 'scopes. They do a comprehensive noise, vibration and balancing kit as an ad-on
https://www.picoauto.com/products/noise-vibration-and-balancing/nvh-overview
Bah, trawling through the wholesalers sites looking for RIFA replacements, hard to find a single supplier for all the values I want.
I'm thinking to use some Y caps instead of X caps for some values, should be ok, right?
You can subsitute a Y for an X but NOT an X in place of a Y.
Y class are used were a failure could cause a risk of shock e.g. live to ground. While the marked "rated" voltage of a Y may be the same as a X the surge and test voltages are higher as is reliability for the Y.
Bah, trawling through the wholesalers sites looking for RIFA replacements, hard to find a single supplier for all the values I want.
I'm thinking to use some Y caps instead of X caps for some values, should be ok, right?
No. The difference is in the failure mode, not the operating mode. (I'm fond of pointing out that amateurs/beginners think about how things work, professionals think about how things fail).
https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/When a Class-X capacitor, also referred to as an "across the line capacitor"—the capacitor placed between line and neutral—fails because of an overvoltage event, it is likely to fail short. This failure, in turn, would cause an overcurrent protective device, like a fuse or circuit breaker, to open. Therefore, a capacitor failing in this fashion would not cause any electrical shock hazards.
If a Class-Y capacitor, also known as the "line to ground capacitor" or "the line bypass capacitor"—the capacitor placed between line and ground—fails short, this could lead to a fatal electric shock due to the loss of the ground connection. Class-Y safety capacitors are designed to fail open. A failure will cause your electronic device to be subjected to the noise and interference that the capacitor would normally filter out, but at least there will be no fatal electric shock hazard.
Meh, the 100n was cheapest in X2 275V, so I ordered 50 of them, but I had to pick 3n3 instead of 2n2 and 270p, and went with a Y2/X1, again bought 50 so should last a while.
Also took the opportunity to rummage through the Rapid clearance section, to stock up on some cheap jelly-bean type stuff, and make sure I got to the free shipping threshold.
Bah, trawling through the wholesalers sites looking for RIFA replacements, hard to find a single supplier for all the values I want.
I'm thinking to use some Y caps instead of X caps for some values, should be ok, right?
No. The difference is in the failure mode, not the operating mode. (I'm fond of pointing out that amateurs/beginners think about how things work, professionals think about how things fail).
https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/
When a Class-X capacitor, also referred to as an "across the line capacitor"—the capacitor placed between line and neutral—fails because of an overvoltage event, it is likely to fail short. This failure, in turn, would cause an overcurrent protective device, like a fuse or circuit breaker, to open. Therefore, a capacitor failing in this fashion would not cause any electrical shock hazards.
If a Class-Y capacitor, also known as the "line to ground capacitor" or "the line bypass capacitor"—the capacitor placed between line and ground—fails short, this could lead to a fatal electric shock due to the loss of the ground connection. Class-Y safety capacitors are designed to fail open. A failure will cause your electronic device to be subjected to the noise and interference that the capacitor would normally filter out, but at least there will be no fatal electric shock hazard.
I have to disagree with that. You can't design a capacitor to fail open per se. You can design it to be much less likely to fail short or / and to limit the current / energy passed if it does suffer insulation failure. The first is done by thicker dielectric and larger creapage / clearance paths combined with enhanced quality control and testing. The latter by adding a fusible element or using very thin foil / metalisation. However the first failure - short circuit - has to pass current for the limiter to operate.
Sprague made capacitors that fail open
Ditto. And you would be surprised how many Americans, even folks my age, have absolutely no clue how to drive a manual gearbox. Present a typical driver with a vehicle with 3 pedals and it's total panic. Automatic transmissions really started to take over in the 1960's and many folks never had to drive a stick and never learned.
I had a friend teach me to drive a manual in the late 70's. I didn't have my first manual car until the late 80's, a 1980 Toyota Tercel hatchback. Both Mrs GreyWoolfe (55) and I(64) can drive manuals. I find them fun to drive outside of occasionally getting caught in traffic jams. My 92 Ford Explorer had a rather heavy clutch and Mrs GreyWoolfe didn't much like driving it for that reason but I enjoyed the beast. I had a 2001 Chevy Cavalier almost from new and put 100,000 miles on it in 2.5 years. It was easy to drive without using the clutch for anything but first. I only did it to show off and prove it can be done to non believers. Of the 3 manual cars I have owned over the years, I miss the Explorer the most.
I had a friend teach me to drive a manual in the late 70's. I didn't have my first manual car until the late 80's, a 1980 Toyota Tercel hatchback. Both Mrs GreyWoolfe (55) and I(64) can drive manuals. I find them fun to drive outside of occasionally getting caught in traffic jams. My 92 Ford Explorer had a rather heavy clutch and Mrs GreyWoolfe didn't much like driving it for that reason but I enjoyed the beast. I had a 2001 Chevy Cavalier almost from new and put 100,000 miles on it in 2.5 years. It was easy to drive without using the clutch for anything but first. I only did it to show off and prove it can be done to non believers. Of the 3 manual cars I have owned over the years, I miss the Explorer the most.
I was taught manual, as most people here are -- you can get "automatic" as a condition on the license, like "glasses" -- which means that you may
only drive automatics. I almost exclusively drive manual, and when I end up in an automatic I've been known to mistake the brake pedal for a non-existent clutch. FYI the clutch operation muscle memory for most people is to kick it down, more or less. This has consequences if you try the same with a brake pedal...
They moved the 3D Printing topics to a corner "Off Topic Hobbies"
Off Topic 3D Printing? Electronics is the core of those machines....
https://www.eevblog.com/forum/supporters-lounge/off-topic-hobbies/new/#new
I do not understand.
Well, I could quite successfully argue that electronics was the core of many devices nowadays, would that make them automatically 'on topic'? I think not. Would the fact that one of those PeletonTM style static exercise cycles would be impossible to make without a shitload of electronics make static cycling 'on topic'? Making one would be*, but just using it? No.
The same applies to 3D printers, CNC mills and lathes and so on. One can see how all those have a peripheral rôle in electronics construction, but not as core electronics.
* I have done. Magnets and Hall effect sensors on the rear wheel and cranks, 5 kHz PLL receiver for a heart rate monitor, add Arduino, add serial connection to an old Mac notebook for a display, done.
You do not compile a firmware for many devices nowadays, nor you hack them so easily.
My Ender 5 is no more a 3D printer, it is an electronic playground.
Bah, trawling through the wholesalers sites looking for RIFA replacements, hard to find a single supplier for all the values I want.
I'm thinking to use some Y caps instead of X caps for some values, should be ok, right?
No. The difference is in the failure mode, not the operating mode. (I'm fond of pointing out that amateurs/beginners think about how things work, professionals think about how things fail).
https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/
When a Class-X capacitor, also referred to as an "across the line capacitor"—the capacitor placed between line and neutral—fails because of an overvoltage event, it is likely to fail short. This failure, in turn, would cause an overcurrent protective device, like a fuse or circuit breaker, to open. Therefore, a capacitor failing in this fashion would not cause any electrical shock hazards.
If a Class-Y capacitor, also known as the "line to ground capacitor" or "the line bypass capacitor"—the capacitor placed between line and ground—fails short, this could lead to a fatal electric shock due to the loss of the ground connection. Class-Y safety capacitors are designed to fail open. A failure will cause your electronic device to be subjected to the noise and interference that the capacitor would normally filter out, but at least there will be no fatal electric shock hazard.
I have to disagree with that. You can't design a capacitor to fail open per se. You can design it to be much less likely to fail short or / and to limit the current / energy passed if it does suffer insulation failure. The first is done by thicker dielectric and larger creapage / clearance paths combined with enhanced quality control and testing. The latter by adding a fusible element or using very thin foil / metalisation. However the first failure - short circuit - has to pass current for the limiter to operate.
I certainly wouldn't want to regard allaboutcircuits as correct in all respects; it was merely the first reference I found.
There are building materials that, while they do burn, are not regarded as a major fire hazard since a small ignition source is sufficient to cause the material to retract away from the ignition source. Loft insulation made from recycled plastic bottles springs to mind.
I was quite picky about which caps I ordered; no metallised paper, no chinesium. So I got Kemet polypropylene foil jobbies.
Hmmm, mystery Hermes parcel, too small to be the counter, I wonder what it is? Off to unwrap it...