Low voltage via shore power cord

[jpcoll01]

Installed Easystart today, the install was fairly easy. After install and leaning cycles I started getting a "stall" indicator and the voltage was dropping which would kick the  Easystart into a safe mode and turn off compressor. This happened on both my yamaha 2000v2 and plugged in to a 15 amp plug in my garage via a long extension cord. Everything starts fine, very little draw from compressor then bang everything slows down. Perplexed I tried it on my onboard gen (5500ish watts) and all works well, no slow down, no dip in power, etc. what I'm asking is what is inline for the shore plug that isn't in play for the gen? 30-20 amp adapter at end of cord? Something in the cord itself? It actually popped the breaker in my garage a couple times. 

Any ideas appreciated. 

[Mark and Dale Bruss]

What is the gauge of your extension cord?  When we got our first motorhome, and park in on the cul-de-sac, we needed about 80' of extension cord.  Having problems running things we found the voltage going into the motorhome was about 95 volts.  That was with a very typical #16 gauge extension cord.

Spent the money for a #10 100' extension cord and I got 120 volts at the motorhome.

[Yarome]

Do you happen to have a clamp meter... or know of someone who does you could borrow from to trace the load?

Inline? The common between your shore power and genny would be the adapter, your leading cord plug, the cord itself, the tail cord plug, the RV receptacle, the line feeds from the receptacle to the ATS (Auto Transfer switch) and lastly the shore power side of your ATS.

[That was assuming you are using the 30-20amp adapter on both the genny and to plug in to the extension cord. I'll come back to that.]

Since it is behaving the same on Genny or home power I think you're on the right track. Gotta be something hinky in your cable, RV receptacle or in your ATS.

That's what I "know" of, that is. You didn't mention a surge protector or EMS so I am assuming you're not running either/or.

Sounds like you might have a loose connector issue or a resistance problem. I would start at the end (the adapter) and then work your way "upstream" to your rig. You can start with a visual inspection for any issues, but you're really going to need a meter to check each component. Alternatively, swap out the adapter and shore power cord, inspect and clean the RV's exterior receptable and see where it goes from there. If you get the same results then it would be time to move to your internal connections.

*Getting back to the house breaker tripping. You didn't mention anything about your genny tripping, so if it was working perfectly during the aircon shut-down, but you're getting a breaker trip on the house.. your extension cord may be too long or not heavy enough gauge to support the load being put on it. That would be a seperate issue from what's going on with the aircon.

That's a start anyway. If I had to make an uneducated guess .... I would be opening up your shore power cord ends and cleaning the RV's exterior receptacle first. Secondly, the transfer switch. Third, the exterior receptacle to the transfer switch connections.

[Yarome]

10 minutes ago, Mark and Dale Bruss said:

What is the gauge of your extension cord?

Ya beat me! 

[Kirk W]

2 hours ago, jpcoll01 said:

his happened on both my yamaha 2000v2 and plugged in to a 15 amp plug in my garage via a long extension cord. Everything starts fine, very little draw from compressor then bang everything slows down.

The extension cord could be part of the problem for the outlet but it clearly didn't impact the generator operation. The adapter may be a factor, but the main difference is that your on-board generator is capable of supplying 45a at 120v, while your Yamaha is only capable of a constant load current of about 15a of continous current load. I'd bet that your air conditioner is one that is drawing close enough to that that the Yamaha is overloaded and thus the voltage is dropping. The Easy Start lowers the starting current and that shows to be working but it does nothing to lower the run current of your air compressor. 

[jpcoll01]

Will get a clamp meter and try to run it down, will start with the cord/plug hooked to the RV and see if there is anything suspect going on. I agree that the AC is likely right at the limit of the Yamaha but the guy from MicroAir said he has no problem with this model and the Yamaha. Also interesting/confusing is the fact that I have run the AC via the adapter and cord many times before with no issue. Which would normally make me say "well clearly you messed something up today" but it works like a champ on my big gen and doesn't bog it down nearly as bad as it used to, which to my amateur brain means the Easystart is working. 

I was originally using a small cord today (again, that I have used 100 times when loading up, etc) but after the first issue I switched to a much larger extension cord (10 gauge). 

Appreciate all the ideas. Keep 'em coming. 

[Kirk W]

13 minutes ago, jpcoll01 said:

Which would normally make me say "well clearly you messed something up today" but it works like a champ on my big gen and doesn't bog it down nearly as bad as it used to, which to my amateur brain means the Easystart is working. 

When you used the extension cord in the past, did you use any kind of line monitor device that would have shut you down if the voltage were to fall below acceptable limits? It seems that the Easy Start has that protection built-in and is what is shutting things down. Those of us who use the Surge Guard or Progressive EMS might very likely see that same thing happen even without the installation of an Easy Start. Have you monitored the voltage to see what it is actually doing? I'm guessing that your voltage is dropping into the 108v range but you never knew that before when using the extension cord. Operating a 120v-ac motor at voltages under 108v will cause the motors to draw excessive current, making the problem get even worse and overheating the motor. Over time this will damage the motor and shorten the useful life. It is the very thing that is the main reason that so many of us use the line monitor devices. 

[jpcoll01]

22 hours ago, Kirk Wood said:

When you used the extension cord in the past, did you use any kind of line monitor device

I have not. Would this low voltage situation likely happen on two extension cords (but same outlet/breaker) and the Yamaha Gen set?  I am camping at our river (Ohio river in KY) property this weekend and currently listening to the soothing sounds of my on-board gen to keep the dogs cool so haven't had time to get a clamp monitor.  On the bright side a barge just went by and the wood fired pizza oven is almost to cooking temp. 

[Kirk W]

14 hours ago, jpcoll01 said:

Would this low voltage situation likely happen on two extension cords (but same outlet/breaker) and the Yamaha Gen set?  

 

It would. When the current demands exceed the capacity of any power supply, voltage begins to sag unless the circuit breaker opens first. 

If you have ever used a lawn sprinkler with a too small hose that is long, you have probably noticed that it doesn't get as much pressure at the sprinkler is it would with less hose of a larger diameter. Extension cords are to electricity exactly as a hose is to a water supply. A small diameter hose supplies less water & a small diameter wire supplies less electricity. In electricity, the voltage is the driving force and is equivalent to the pounds per square inch (psi) in a water system and the current (amps) is a measure of quantity just like gallons per minute (gpm) is for water. 

[jpcoll01]

Got back to the house about an hour ago and started my investigation. Pulled out about 10 feet of my shore cable (attached to motorhome not a separate cord) and gave it a good once over and didn't see anything. This is about as much of the cord as I have ever pulled out.  Decided to go over he rest of the cord and, about four feet from the end I see electrical tape   First thought was shame on me for not checking this entire cord when I bought the rig in Oct, but then I started removing electrical tape, probably 1.5 rolls of electrical tape later this is what I found.

I cut the ends clean put on new butt connectors and put it back together correctly and now have an AC that will run from my Yamaha EF2000isV2.  Thanks for all of the input, I feel silly for not having checked this before. I guess it always just powered through since I was normally plugged into at least 20 or 30 amp. 

[Yarome]

3 minutes ago, jpcoll01 said:

.....1.5 rolls of electrical tape later this is what I found.

OUCH! Yep.. that'll do it. Good thing they used 1.5 rolls of tape though. That would have been a fire waiting to happen. Good find and bet you'll sleep a lot easier tonight. 

[Kirk W]

2 hours ago, jpcoll01 said:

I cut the ends clean put on new butt connectors and put it back together correctly and now have an AC that will run from my Yamaha EF2000isV2.

 

Splices introduce resistance which equates to both a loss of voltage and heat generated in the connections. If it were me, I would put replacement of the existing cord with a new one into the budget for the future. You can get on that is 30' long from Walmart for $44 or you can get one that is 40' long from Amazon for $60.

[Yarome]

1 hour ago, Kirk Wood said:

If it were me, I would put replacement of the existing cord with a new one into the budget for the future.

Wholeheartedly agree. At least the immediate issue is resolved and you're good to go in the interim. The EasyStart safegaurds probably helped identify a long term issue that could have developed into much more than it turned out to be. 

[jpcoll01]

I will put that near the top of my list. Have to track it behind the wall and see where it disappears to so I can wire in the new one. 

Concerning the Easystart I was too quick to declare victory. It works about every third compressor cycle. It was pretty humid here today so that might have been part of it. Likely my 15k BTU AC is just too much for the 2000 watt gen even without the start stress from the compressor. 

[Yarome]

28 minutes ago, jpcoll01 said:

Likely my 15k BTU AC is just too much for the 2000 watt gen even without the start stress from the compressor. 

Very likely. A 15k AC's running draw is "likely" to be somewhere between 15-18amps. Your 2k watt genny... at the sustained output level (1600watts) is right on 13.3amps with max output (2k watts) will only peak at just a shade over 16.5amps.

If there is anything else at all pulling juice it's going to be a non-starter.

If you picked up another Yamaha though you could parallel them. The AC would then be a non-issue and you would still have around a good 10amps +/- left over to run other loads.

[Yarome]

I should probably add... what is likely happeneing is that your genny is running near peak output to keep your 15k going, but it's not able to do that indefinately. Once temps reach a certain level it will drop down to the "sustained" output.. which may be too low to keep your AC going.