reduce light flicker?

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Kamakazi

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Does someone make a capisitor to be installed at the service point of a single dwelling to reduce voltage drop due to high inrush current aka (h&a ,water heater, garbage disposals, etc) to reduce light dimming? or something?
 
A capacitor wil do nothing for these problems, larger service drop or lateral conductors, larger power company transformer, shortening the distance from transformer terminals to the house are a few things that can make a difference
 
Never heard of a capacitor on an AC system for this.

Now,you could do it with a motor-generator, with a really big flywheel, with VA sized for the lighting circuit(s); or an inverter running off batteries that are constantly being charged (as long as the source is present).
 
Al,

Would it help to isolate the lighting circuits thru its own transformer and panel, or would

the " dip " in voltage still be seen when heavy loads come on.
 
100217-0751 EST

Kamakazi:

Connect your Fluke meter with min-max monitoring to an outlet with one of the lights you see flickering, actually a momentary dip or a sustained dip not flickering, and report back what min and max voltages you see.

Flickering as a descriptor of light problems is probably better used to describe a random uncorrelated change in light intensity that likely would be a result of one or more bad connections. This would derive from the use of flicker in describing a flickering candlelight,

Tungsten filament incandescent lamp light intensity is quite sensitive to small changes in applied voltage. I can visually detect a change of 1.5 V at 120 V when watching a 15 W bulb.

Many CFLs (compact fluorescent lamp) have little sensitivity to voltage change. In particular the GE dimmable has less sensitivity to voltage variations than standard CFLs when supplied from a sine wave source, and the standard CFL is less sensitive to voltage changes than an incandescent. The GE dimmable is adjustable with a phase shift dimmer, a delayed turn-on sine wave, but when supplied with a variable sine wave it has little change down to about 100 V and then just quits.

An 8' Slimline that I have with a magnetic ballast has about 5% change in light intensity form 100 to 130 V.

See my plots of light intensity vs voltage at
http://beta-a2.com/EE-photos.html
In particular photos P 9, 11,14, 15, and 17.

.
 
100217-0843 EST

Kamakazi:

At one of my workbenches I connected my Fluke 27 in min-max mode. Then in the same outlet I plugged in a 1500 W heater. The max and min values were 123.6 and 118.5. This means the source impedance to this point was about 5.1/12 = 0.4 ohms.

If I do this near the main panel the results are a change of 1.3 V for an approximate source impedance of 1.3/12 = 0.1 ohms.

When I monitor the opposite phase the change is not greater than 0.1 V.

Doing some guess work. I believe my pole transformer is 25 KVA. This equates to about 100 A. If we assume a 5% impedance, then we should have about 6 V drop at 100 A or a source impedance of 6/100 = 0.06 ohms for 1/2 of the secondary. Seems to correlate with my measurement.

.
 
benaround said:
Would it help to isolate the lighting circuits thru its own transformer and panel, or would the " dip " in voltage still be seen when heavy loads come on.
Click to expand...
A dip in the primary voltage of a transformer is passed through to the secondary output voltage. There's no appreciable energy storage in a simple transformer that would bouy up the secondary voltage over the quarter to two second duration of a "dip".
 
al hildenbrand said:
A dip in the primary voltage of a transformer is passed through to the secondary output voltage. There's no appreciable energy storage in a simple transformer that would bouy up the secondary voltage over the quarter to two second duration of a "dip".
Click to expand...

Al, when dealing with a load dipping the voltage, it is common in large commercial or even industrial situations to feed the affected load (lighting in this case) from a separate transformer than the offending load causing the voltage drop. The reason this works is that much of the voltage dropped is though the transformer's impedance. I doubt the voltage moves much on the transformer primary inthis situation (residential load starting up).

For a residential setting, many times all that can be done is replace conductors with larger sizes, or replace the transformer with something larger if the flicker is more than the power company's standards allow.

The easiest and cheapest thing to do would be replace incandescants with compact flourescents. If the original poster wants to, they can ask the power company to measure flicker at the meter and see if they need to do something on their side of the meter such as larger service conductors or larger transformer.
 
wirenut1980 said:
Al, when dealing with a load dipping the voltage, it is common in large commercial or even industrial situations to feed the affected load (lighting in this case) from a separate transformer than the offending load causing the voltage drop.
Click to expand...
I understand. The Utility "infinite bus" becomes the "energy reserve".

But, the OP defined the question. The transformer Benaround asked about, and the way I framed my answer for the OP, is a 1:1 turns ratio on the end of undersized utility secondary from a likely undersized PoCo xfmr.
 
al hildenbrand said:
I understand. The Utility "infinite bus" becomes the "energy reserve".

But, the OP defined the question. The transformer Benaround asked about, and the way I framed my answer for the OP, is a 1:1 turns ratio on the end of undersized utility secondary from a likely undersized PoCo xfmr.
Click to expand...

Gotcha, I was wondering if I was not understanding your response. Based on your past posts, I was pretty sure you already knew what I was saying.
 
100220-0745 EST

On my website are photos of plots of line voltage and power at my home. This data is from a TED power monitoring system that I have previously discussed. Also the photos have been previously presented. I had shown these because of the periodic variation that occurred at times of the primary voltage.

Relative to my following comments it is important to note that TED system only measures the voltage on 1/2 of the secondary of my power company transformer. Thus, my load power changes may or may not be on the phase that the voltage is being measured.

For the most part there is not any significant correlation of my load changes with the source voltage changes. Also note that the source voltage changes are generally less than 2 V. At some future time I will get back to some of these whole house measurements.

See photos P22 thru P25 at the end of the web page at:
http://beta-a2.com/EE-photos.html

Based on the almost complete lack of correlation of voltage changes with load changes tends to imply that most of the occurring load changes were on the phase opposite of the one on which the voltage was being measured. This conclusion is based on my known voltage change at the main panel from a test 1500 W load.

.
 
Besoeker said:
Not a reserve, just a "stiffer" supply.
Click to expand...
:)

"Stiffer" is a nice turn of the language, but I was framing mine more with the OP in mind.

"Stiffer" side steps the "infinite bus" idea as well. I like it.

Suffice it to say that the load variation induced supply voltage fluctuations (IR drop) intimated in the OP, in a single family dwelling, wouldn't practically (economicly) be solved by adding another supply transformer.
 
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