What is the lowest voltage you have seen?

[pianotuna]

For me, 97 volts.

[PatJ]

I've seen low 90s; 90, 91, 92 on a hot day. To the point my EMS disconnects me. Unacceptable IMO when you are paying for a hookup site.

I installed a Hughes autoformer, hardwired into the storage compartment so it's out of sight as I've learned many campgrounds do not allow autoformers. It's unfortunate campgrounds cover for their insufficient wiring with a rule to restrict people from using the power they paid for, rather than actually fix the issue.

It was a few years ago, but I'm about $600 total into the autoformer plus the materials needed to hardwire it, worth every penny and highly recommended.

[AllegroD]

97v but I think that is because I was investigating why my coach kept shutting down. Was standing in from of my Kill A Watt when power came back on. Watched it rise to 106 and then (almost immediately) dropped to 97 before my EMS did it's job and disconnected. Might have gone lower.

[BruceMc]

I stand corrected:

CA Traveler wrote:

BruceMc wrote:
The lower the voltage, the higher the current draw... Things are cooking somewhere!

Maybe - resistive loads will have lower amps with lower voltage. Inductive loads like motors will have higher amps if they maintain the same horsepower.

Years ago I measured my A/C, lower voltage resulted in lower amps because the motor produced less HP. Several others reported the same.

Not suggesting low voltage is OK...:B

[valhalla360]

dodge guy wrote:
The highest I’ve seen was 129V, that’s when my EMS kicked in and shut everything down When I reset it, this was at 2 in the morning. the voltage was at 127. I watched it for 15min and it never went back up. Im assuming almost everyone’s AC shut off at the exact same moment LOL!

Nominal 120v power has a tollerance of +-10%, so 108-132v is technically in spec. Seeing voltage north of 125v is fairly common, particularly if demand is low. We see it often mid-week when RV parks are near empty. Then on a hot busy weekend, it will often drop into the 110-115v range (or worse if they don't have a strong power supply).

[wa8yxm]

The thing about low voltages and electrioncs.

THough in days of old when folks were bold there were Radios and the like that actually operated on 120 volts rectified direcr. NO TRANSFORMNER actual line power and if you plugged the plug in and touched the chassis.. Depending on which way the plug (2 blade) was turned.. ZAPP... (you got bit) thankfully you don't see those any more save in vintage stuff. I mean very vintage .

Toay most everything runs on much lower voltages. and a Power supply converts 120 volt AC down to 4 or 12 or something DC. (Those are very common voltages One brand I know uses 14 volt)

THere are basically 3 types of power supplies.

Switching supplies.. If you fed one of those oh say 20 vols AC.. i should be able to deliver 12 VDC all day at full output and not overheat... OR you can feed it 250 volts. . And it will still output 12 VDC and not overheat.. It truly does not care so long as you are feeding it at least about 8 volts AC or more .

Transformer supplies There are types
Regulated SHUNT.. A lower supply voltagte they run cooler
Regulated PASS Same thing

Non Regulated or ferroresonant These may not deliver full output if the voltage drops. Many wal wart are of this type (Low power like phone chargers)

They also will not oveheat.

[dodge_guy]

I’ve seen as low as 106V.
The highest I’ve seen was 129V, that’s when my EMS kicked in and shut everything down When I reset it, this was at 2 in the morning. the voltage was at 127. I watched it for 15min and it never went back up. Im assuming almost everyone’s AC shut off at the exact same moment LOL!

[valhalla360]

pianotuna wrote:

BruceMc wrote:
That's tough on electronics. The lower the voltage, the higher the current draw... Things are cooking somewhere!

Only inductive loads are bothered.

Which is why I invested in an autoformer. Lowest I've seen with the autoformer is 108. I have it set to cut in at about 113.

Disconnected the autoformer at 102v...so outlet was probably down around 92v.

[wa8yxm]

82 volts at the Park outlet per my neighbor's surge protector (Same box) and the autoformer took it up to within the safe range

[MNtundraRet]

Low voltage (Brownouts) can easily happen in rv parks who have not upgraded their electrical systems. On a hot, full weekend, the voltage likely drop with AC units running. I used an AC meter to monitor voltage. I would turn off our air-conditioner when the voltage started to drop.

[Grit_dog]

0?

[pianotuna]

MFL wrote:
My lowest is just below 100. That is when the AC fan is set to auto, and both the fan and compressor start up nearly the same time.

However this low voltage, is just a second or two, so you'd have to be watching the meter closely. It quickly returns to 112-116, depending on other electronics running.

I don't feel this quick spike is hurting anything, and is normal.

What are others thoughts, as to very brief low voltage, on AC startup?

Jerry

I think that there will be spikes. Some folks on other threads have mentioned as low as 65 volts (iirc). That would concern me. And other campers on the same loop would have the spike/brown out happen to their RV's too.

[pianotuna]

CA Traveler wrote:

BruceMc wrote:
The lower the voltage, the higher the current draw... Things are cooking somewhere!

Maybe - resistive loads will have lower amps with lower voltage. Inductive loads like motors will have higher amps if they maintain the same horsepower.

Years ago I measured my A/C, lower voltage resulted in lower amps because the motor produced less HP. Several others reported the same.

Not suggesting low voltage is OK...:B

92 is seriously LOW!

Interesting on the measurements. I've not seen that happening--but to be fair I was not looking either. I merely suffered without roof air.

[pianotuna]

BruceMc wrote:
That's tough on electronics. The lower the voltage, the higher the current draw... Things are cooking somewhere!

Only inductive loads are bothered.

Which is why I invested in an autoformer. Lowest I've seen with the autoformer is 108. I have it set to cut in at about 113.

[MFL]

My lowest is just below 100. That is when the AC fan is set to auto, and both the fan and compressor start up nearly the same time.

However this low voltage, is just a second or two, so you'd have to be watching the meter closely. It quickly returns to 112-116, depending on other electronics running.

I don't feel this quick spike is hurting anything, and is normal.

What are others thoughts, as to very brief low voltage, on AC startup?

Jerry