Blinking LED light bulbs

northerner

I'm having an issue with LED light bulbs that are blinking when they're not supposed to be.

They are a Globe (120v edison screw in) LED 8 watt vanity bulb that when turned on (no dimmer switch is ever involved) often come on at about half intensity, and then blink to a normal intensity a couple of times. This can continue for quite some time, or eventually come on and stay at full intensity. I have 2 bulbs doing this and they both show similar behavior.

The funny thing is, they don't blink (or dim down) on a separate power source (ie my inverter and solar panels), but only on the line from the utility company. They come on as they should and stay at normal full intensity, on my pure sine inverter. I tried the bulbs at a different location in town, and they exhibit the same strange dimming behavior.

Another funny thing is they both started doing this after a recent power outage. This happened twice now, just recently and also during a power outage that goes back a few months. The first time the bulbs eventually returned to normal operation. They appear to be doing the same thing again, as they don't blink as often as they did about a week ago? Very odd.

Has anyone seen this type of behavior or perhaps could offer an explanation? I'm thinking that the bulbs are faulty? I have other LED bulbs from other manufacturers that don't exhibit this behavior.

vln

It sounds like the circuit board that controls the LED's is fried from a surge that happened after or during the outage.

northerner

Yes, it could be an issue with a semiconductor in the circuit board. Why it has affected these 2 bulbs and not any of the other types is a mystery? It could be that these bulbs have an inherent weakness? Also strange that they show no ill effect on my own power source. They seem to act up more after initial turn on and will eventually stay on after a few blinks. At least that's the case now. A few days ago, they just kept blinking (both of them). That is very bizarre that they show similar behavior at different times. Perhaps the line voltage is changing a little over time and there is a sensitivity to it with a fault?

I'm thinking of returning the 2 bulbs if possible, but I'm wondering if this fault will show up on another power source?

I had a utility line technician look at the problem, but he didn't have any answers. He said that the power is monitored continuously and shows no problems. He also mentioned that pings are sent down the lines for various meter readings throughout the region, but that shouldn't affect the bulbs?

northerner

The LED bulbs are back to working fine again on the utility power and not blinking at all now.

k_buz

ghosts?

But seriously tho...is there a second floor above this area? Maybe someone walking or kids playing could jostle a loose connection in the lamp or socket?

northerner

I've ruled that out as the bulbs exhibited the same behavior in different lamps and even at another building on the other side of town. Gremlins in the power lines maybe?

Just checked the bulbs again and they're acting funny again! I think I will return them.