If you find capacitors failing often, it's worth checking the voltage across them while they're running (will often be higher than line voltage) and comparing that to their class. Caps that are under their rated value will cause a motor to run slower and hotter as they're usually permanent split capacitor motors (the cap is always in circuit and helps keep the torque up), but until they get really low you won't notice it as much. I've found that wholesalers/supply houses tend to sell the cheaper caps with lower lifespan. However that one you pulled out was class A at 420V, which should last way longer than it did, unless the voltage across the cap is wicked high. Class A specifies an applied life of 30,000 hours Class B specifies an applied life of 10,000 hours Class C specifies an applied life of 3,000 hours Class D specifies an applied life of 1,000 hours You'll see on the capacitor the class and a voltage rating. Often multiple, different classes for different voltages (higher voltage, lower lifespan). Something that says Class A 420V should last forever (30,000 at 420v) vs. something that says class C 420V, which won't last too long (3000h at 420v). Online electronics places are the best place to get good quality caps (element14, farnell, RS components etc, not sure what services the UK), could be good to upgrade your stock to reduce callouts.
@SeanBZA8 ай бұрын
Farnell and RS are UK companies.....
@heavydiesel8 ай бұрын
Thanks for the info! I generally buy my capacitors from RS components, usually buy in bulk to get a discount for the common sizes. I have some sites where every year the capacitors are out of spec so get changed and others where they last years, I wonder if its down to the quality of the mains supply.
@SeanBZA8 ай бұрын
@@heavydiesel Time to suggest to the ones who have them fail regularly, that installing some proper (as in not bought off fleabay or temu) surge arrestors in the main distribution board will likely help, and reduce the chance of the expensive electrical and electronic controls, along with LED lighting, being damaged. they probably are finding that LED lights do not last either, which says surges.
@SeanBZA8 ай бұрын
@@liam3284 True, but you need them on the incoming feed, then again on the board that supplies the milking parlour as well. You can also add MOV units to the control cabinets as well, but till you have the primary side done you will get nuisance fuse blowing, as they will be trying to clamp all the surges. I have a lot of them around, mostly at point of use, and have had a few fail due to mains surges. I add them to LED lights outside, because those tend to fail from spikes, and the extra protection does help a lot.
@Thermoelectric78 ай бұрын
@@liam3284 I'd imagine switching transients don't do the caps any good, but it's in series with the motor winding which will help to limit those transients, and it doesn't appear to be impacting the unit right next to it which would run at the same time. Something weird going on there, or that was somehow just a bad cap from the factory
@FrontSideBus8 ай бұрын
Some caps do have quite a distinctive smell.
@heavydiesel8 ай бұрын
Yes, back when I started working and the oil filled ones were common, they'd have a sort of orange smell to them, they used to fail because the aluminium casing wore through from vibration, very rare to get one test below spec.
@More350Power8 ай бұрын
Easy Fix ! Thanks for sharing!
@heavydiesel7 ай бұрын
Thanks for watching!
@gerardomireles1228 ай бұрын
Thanks again heavydiesel very cool interesting Cool tools ratchet screwdriver Good tool
@heavydiesel8 ай бұрын
Yes that Bahco screwdriver has lasted well, mys be nearly 20 years old!
@NorCal-refrigeration8 ай бұрын
Good stuff. 🤘⚡️🤘✨✨✨
@heavydiesel8 ай бұрын
Thanks!
@stuartjomes72898 ай бұрын
John do these motors have run and start capacitors or only start ..
@heavydiesel8 ай бұрын
Its a PSC motor (permanent split capacitor) so the one capacitor is in circuit all the time.
@SeanBZA8 ай бұрын
Yes caps fail, though the date code on the other does give a clue as to the age of the cap, as it has likely only been sitting a year before install.
@Thermoelectric78 ай бұрын
Realistically that style of capacitor shouldn't have any issues sitting on a shelf for a while, they don't really age. Just a thin piece of plastic with thin foil either side wrapped up. Cap definitely should have lasted longer than it did.
@SeanBZA8 ай бұрын
@@Thermoelectric7 Cheap chinese junk with plastic film a little too thin for the voltage, and thus the film breaks down a little with each start, and self heals a little capacitance away each time. You really want to have 2 in series, double the value, to actually have a decent life.
@heavydiesel8 ай бұрын
Yeah I buy them in bulk to get a discount!
@Thermoelectric78 ай бұрын
@SeanBZA anything you buy from a reputable retailer should have accurate lifespan ratings on them, lots of good brands out there. But yeah, good chance the Chinese ones lie. Be mindful if you put them in series you halve the capacitance. You'd need to use two capacitors twice the size of the original for that to work.