Espresso PID dimming...

This topic has come up at least twice in H-B in the past.
The surge you speak of is in my mind a quick dimming of the lights in my house. Not all of them, a few. It also affects the pump the way you describe. So it is a voltage drop and noticeable to the human eye, ear and small motors like the pump and grinder.

Option 1 You could see if your PID can have the Time Base changed from Variable or 1 second to maybe 5 seconds or more. It's possible with the Watlow model on my Quick Mill Alexia. Easy, cheap and things will work ok and in 8 seconds you may forget what the pump sounds like.

Option 2 My Alexia has a supplier installed PID and it came with a relay which disabled the boiler heater when the pump was engaged to run. If you were to grind at the same time, then you would be clear of the problem. Not all grinders are affected by this power dipping, mine has a DC motor and that may help??

Option 3 Electricians... a dozen who I've spoken to, do not understand the PID espresso machine. It exists nowhere in their field of experience. A high-tech industrial electrician might know what's going on. I've not met one.
Now I've found this espresso machine dimming of power to be minimal in a new house with a 200 amp service and a 12 gauge wire run to a dedicated espresso machine outlet.
It gets worse in a house with a 100 amp service and the same wiring. And it gets worse yet when running on a 50 amp whole house generator. I make sure I engage the PID cut out relay when pulling shots to keep the pump running evenly. The coffee tastes the same whether I do it or not.

Thinking these facts over, I suspect if you ran an 8 gauge wired power outlet to a 400 amp panel, the problem might go away. Not practical however.

One last thought was that a massive auto-transformer installed at the espresso machine outlet might minimize or prevent this power drop. Counter space and cash prevent that option.

Good luck,
Dave

With a cold machine, the elements are at minimum resistance. Current draw is highest and line voltage drop is maximum. It's not normal for a circuit to drop enough voltage to cause a small motor to noticeably slow down. The Niche is only 180W and a 20A circuit should handle easily 30A for about an hour. The Niche was not grinding in the video, so the load is about 50w.

The missus uses 4x 1000w waffle irons on a 20A circuit, and has done for decades, without ever popping the breaker, dimming the lights or any other anomalies. The loads are not synchronous, so average draw is well below the 20A rating. She uses her 750w mixer on the same 20A circuit as the espresso machine and grinder. Neither the mixer nor the grinder is affected by the espresso machine PID pulses.

A Niche connected to a variac needs more than a 10VAC reduction to get even close to the pitch change in the video. 12ga wire is 1.5Ω / 1000 feet. To drop the approximately 10v need to slow the Niche, the run would have to be about 200 feet with good connection integrity.

Something you might want to have an electrician check is the mains / meter connection integrity, wiring in the breaker box, breaker reseat, breaker to wire terminal, wire to outlet terminal. All of the preceding can contribute to significant voltage drop, particularly in older building and humid corrosive environments. Living on the coast, we check every five years or so.

Sadly, outlets today use quick connects. Couple them with crappy installation practices [stripping the wire before plaster & paint or long before outlet connection resulting in badly oxidized wire] and voltage drops can be significant. In every house we've owned, on all non-lighting circuits, ALL quick-connects are rewired to the screw terminal after cleaning the stripped end.

It's not normal for a properly sized and maintained circuit to show any anomalies until well above the rated current.

!! DO NOT ATTEMPT YOURSELF IF YOU ARE NOT FULLY QUALIFIED !!

If you live in an apartment, my condolences. Many years ago I had to parallel two computer power supplies with the A/C out of phase to prevent the computer randomly crashing.

Here is the latest. Definitely a bit of vintage drop, should this affect the motors speed, the light on the back and the speed of a grinder plugged into the same outlet? Is it my wiring or the machine?

so it looks like my line voltage goes from 122.7 to 114.8 at its most extreme with the PID cycling on and off. if the pid cycles on and off like this normally and there is a voyage drop, is this the same for every pid machine? granted my drop may be more than others, but if this is how the pid works, everyone must have this same issue of voltage drop, right?

It is highly unlikely to be your machine. An IR drop measured at the receptacle happens due to resistance in the circuit, not in the load. This can occur due to very long wire runs, too thin a wire gauge, bad connections in the circuit, a bad main connection in the load centre, or a bad connection at the utility. You've already moved your machine to other circuits and reported the same phenomenon. You did not respond to my suggestion to take the machine over to a neighbour's house and see what happens; the same operation there would have eliminated all the above possibilities. There is another test you can do at your house to narrow it down. Put your meter on a different circuit from your machine. Run your machine. If the IR drop you see is about the same, then it is happening on the main connection in your load centre or at a utility connection, or it's normal. But, from your video, I think it is too big a drop to be normal for a 20-amp circuit. For what it's worth, I've measured the drop on my circuit, which is a dedicated 20-amp, 40-foot direct run to the load centre. I get about a 1-volt drop as the heater cycles. My machine is different from yours, but the heater is likely about the same.

If the meter has Min/Max function, use that to record min & max.
The min is likely lower than the displayed.

By comparison, ≈2.2v delta here on 123v with both heaters active.

Haven't been able to take it to a neighbors house as I've been working crazy hours. I did put my multimeter in a different outlet on a different line in the kitchen and no fluctuation while the pid cycled on and off. That line, when I tested the machine there cycled from @ 123 to 118 v. not as bad but still noticeable when the light on the back of the machine pulsed

I also think it's the machine. The line power to the outlet would have to be severely compromised to allow the machine pump (or anything else in the machine) to "surge" in that fashion if the machine circuits are working normally. It sounds exactly like there is some switching component in the machine, probably connected to the heater-PID circuit, that is causing an intermittent large fluctuation in current draw. A good way to check this is to put an ammeter or some sort of wattage measuring device on the power cord to the machine and check for such power fluctuations while the machine is running.

It's unlikely there is 'another path' as it would likely trip the GFCI.

It's marginally possible the heater element is incorrect.

Those kind of voltage drops are completely consistent with undersize wire, failing breaker, several quick-connect in series, oxidized or loose connections, non-code installation...

Pressino wrote:<snip>A good way to check this is to put an ammeter or some sort of wattage measuring device on the power cord to the machine and check for such power fluctuations while the machine is running.

This is a good idea, if for no other reason than to get some peace of mind about the machine. A Kill-a-watt or one of the cheap Amazon copies would be the best. Plug the machine in and start it up from cold. The heater should come on steady at first, giving you the max current drawn "full on". It should work out to be more or less the same as the specified power on the nomenclature plate. Another quick test of the machine would be to plug it into a 15-amp circuit, turn it on from cold, and see what happens. Most prosumer espresso machines are made to run on a 15-amp circuit without overloading it. If there's something inside the machine that is drawing significantly more current (which I still say is unlikely), then after a short time you'll pop a 15-amp breaker, whereas the 20-amp one you normally use may not trip. This test would not tell you if inside the machine there are other faults.