PCB: low voltage On-Off switch drives AC mains relay \ includes soft start .. H9KPXG

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#222
Mouser.com found these three in stock:

https://mou.sr/31BvDH0

I simply used their parametric search to find all IN STOCK devices whose parameters matched the data given in line 15 of the Detailed Parts List

  • Film Capacitors
  • Value = 22nF (0.022uF)
  • AC Volts = 400V or higher
  • Lead Spacing = 7.5mm
  • Body Size = 5 x 12.5 mm or smaller
Me personally, I'd pick the one with the cute red plastic exterior. I'd avoid the one with no exterior at all, the one whose description says UNCOAT. But you are not me; exercise your free will
 
#231
Substitute Parts

Mark Johnson said:
Mouser.com found these three in stock:

https://mou.sr/31BvDH0

I simply used their parametric search to find all IN STOCK devices whose parameters matched the data given in line 15 of the Detailed Parts List

  • Film Capacitors
  • Value = 22nF (0.022uF)
  • AC Volts = 400V or higher
  • Lead Spacing = 7.5mm
  • Body Size = 5 x 12.5 mm or smaller
Me personally, I'd pick the one with the cute red plastic exterior. I'd avoid the one with no exterior at all, the one whose description says UNCOAT. But you are not me; exercise your free will
Click to expand...


Thanks Mark, I would have commented earlier but "High School Homecoming on Friday and a Wedding tonight" busy at the Ranch this weekend.

I am learning that a "Detailed Parts List" In fact has many details. Using the search function at Mouser is starting to make sense. I was able to get the same results at you going across line 15 of the Detailed Parts List.


Now if I can just find the IRM-02-5 Looks like Jameco has them.


Thanks again
 
#233
PRR said:
Do you soft-start water well pumps?

My domestic well pump pulls 44A @ 125V, 5,500VA, at start-up. (1,320VA when running.)

Our utility power absolutely does not care about that surge. When the utility power is out, it is risky to start the pump on my engine-generator backup.
Click to expand...

Since continuity and power quality are absolute goals everything more than 500 VA needs soft starting. Allowing heavy loads to be switched directly will cause of brownout or glitch which is unwanted for other users of the grid. The power companies here do care about surges and blackouts are very rare. In my profession I have experienced various times that matters are met quite seriously.

Normal homes are limited to 16A 230V. For higher power a 3 phase connection is needed and this will cost a lot more so most homes are limited to 3680W. To cater for induction stoves another phase may be used (2 phase) to avoid the higher costs of 3 phase.

Your well pump would only be allowed here when it does not consume more than 12x I nominal at power up and is equipped with a motor protection breaker and a soft starter. You see 230V has advantages as your pump would consume 24A for a very short time but in practice the mandatory soft starter will limit current.
 
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#234
> Your well pump would only be allowed here when it does not consume more than 12x I nominal at power up and is equipped with a motor protection breaker and a soft starter. You see 230V has advantages as your pump would consume 24A for a very short time

About 90% of well pumps here in 0.5HP-5HP sizes are 230V. But at 0.5HP 115V pumps are also offered. I do not know why. In fact my main box offered a 230V feed to the well, but was connected for 115V.

I do have a 230V 0.75HP pump on the shelf, but it is not fun to pull a pump in a 30 meter hole.

> 12x I nominal at power up

Note that my pump start-up is 4X running. Nowhere near 12X. In fact nearly all residential motors are 3X start-up by industry agreement. And it would be hard to build a 12X starting current motor smaller than a car.

Yes, power quality and reliability is very casual here. Good, but sometimes it seems selling-out the company is more important. My power company has had three names in 5 years, and there is talk of another buy-out. But the main trouble out here is not my pump-surge or the neighbor's arc-welder, but Jeeps hitting power poles or trees falling on the wires. (No, can't go underground, all rock just below the surface.)
 
#235
The 12x I nominal is by design the maximum so without any added stuff and it is nothing abnormal for an electromotor (certainly when it is 3 phase). In practice it will be equipped with a motor protection breaker and soft starter to limit exactly that start up current. It also depends on the motor/transformer type and the duration of the start up surge. Since normal homes have class B circuit breakers the breakers would otherwise simply switch off. There are many details involved and practically everything is regulated. Although I am not too fond of too much regulation in this case the positive results outweigh the negative effects by far as the grid is reliable. When the EU limited vacuum cleaners to 900W I thought this went too far 🙂

Too much information for now and also in the wrong thread 😀 If you have the choice to use 230V pumps I would choose those as cabling can be thinner/cheaper, losses are lower and startup current is less.
 
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#236
Today I had the time to finish my H9KPXG.
Thank you Mark for sharing this project

I've used the 250j thermistor and I had to work on its legs with my Dremel to be able to fit it on the pcb

It's really a big boy 🙂
 

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#238
I don't have a big inrush limiter to show off but it did occur to me I never posted the finished project with my H9KPxG installed. I purchased my switch from Oznium (Bi-Color Anti-vandal LED Switch | 16mm Push Button Enclosure) because the red/blue bicolor LED I wanted for my M2X was in stock and shipped quickly. It may be cheaper somewhere else but it's a good quality switch. Like Mark, I prefer not too bright LEDs that are perfect for a dim room.
M2X Blue.jpg

M2X Red.jpg

Red = Off, Blue= On
 
#239
Woo, that is drop dead gorgeous! Congratulations to Audiobear!

Although I think it might give the EU regulators a little less fibrillation of the rectum, if you were to refer to those two power states as "Standby" and "On" in your published literature which they may read one day. How can it be "Off", when an LED is illuminated?, after all. If they desire Really And Truly "Off", they must flip the back panel mounted, IEC mains-inlet integrated, EU hiney-meat fibrillation preventing, DPDT switch. Now it is truly Off.
 
#240
Good point. It raises a philosophical issue about just when off is off. I will do Standby and On. No problem. I don't know EU regulations but it may be that less than 0.5mW is "off." Certainly is from a low energy perspective. By the way, the AC mains is plugged into a smart switch that responds to Alexa but obviously when I use that 3rd switch I don't see the red LED.

I should also mention that Mark's IPS#7 is installed in the M2X and some very gratifying and interesting listening is taking place by rolling not only op amps but pre-amps. More to come on the M2X thread.
 
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