Skip to main content
Topic: Chasing my tail: No AC shore power (Read 532 times) previous topic - next topic

Chasing my tail: No AC shore power

I taught myself a good lesson today:  Use Occam's Razor.

We were into our second night at a brand new RV park.  All looked good, except the water pressure was 110psi, so I used my regulator and told the management.

Woke up this morning wondering why the heat pump wasn't working.  My AC monitor was blank.  No AC power.  Went outside, the breaker was on, the surge protector was showing the correct LED colors.  Flipped the breaker off and on, no CLUNK of the ATS.  The good news was the generator and inverter worked. 

I drove to tonight's park, all the while thinking how to trouble shoot this.  It had to be the leading ATS.  The next one in line was working, it clunked for the generator,  and the third one was working with the inverter.  I was thinking the most likely problem was the voltage sense device, that orange box that tells the ATS if the voltage is within the safe range.

I guess I was right, but the problem was not the orange box, the park voltage must have been out of range and my smart ATS refused to activate.

I should have measured the voltage at the pedestal before leaving the park.

And looking back, my neighbor had an external EMS, and it's light show was different when I left than earlier when I had power.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Chasing my tail: No AC shore power

Reply #1
Sounds good to me.

What park were you at?
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Chasing my tail: No AC shore power

Reply #2
Sounds good to me.

What park were you at?

Verde Ranch, near Verde Valley, and cottonwood AZ. Passport America. Will be a great park very soon.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Chasing my tail: No AC shore power

Reply #3
It happens more often than you think.  Years ago I moved my machine shop into the new building, so new the electricity was still being run.  I asked the electrician what was up and he showed me what he'd found: 11,800 volts connected directly to the main panel in the building.  Amazing how fast Public Service of New Hampshire can move when it's not only their fault but a life safety issue.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Chasing my tail: No AC shore power

Reply #4
After some discussion here a couple of years ago, I made a simple tester, and last year made another one for 30A. The first one is a 50A pigtail connected to two regular outlets, so that there is 110 on each one. Each duplex outlet gets a digital voltmeter and an orange tester to tell whether or not it is wired properly. On the side is a 250V neon light that glows if the outlet is capable of putting out 250V (not all are). Don't need 240 on this coach, but nice to know.

The second one is a 30A to 20A dogbone. When I need it I just steal a volt meter and tester from the 50A one. Yes, I could just stick the probes from a regular multimeter into the outlet, but these two are kept right by the electric cord and adapters, so it is very easy to check.

FWIW, once I'm happy with the pedestal I turn all breakers OFF until I'm done connecting things. If I'm at a site that has 50/30/20, all three breakers are off until I've got things connected, then I turn on whatever I need, usually the 50 and 20. When I get ready to leave all breakers are OFF.

Re: Chasing my tail: No AC shore power

Reply #5
No AC power.  Went outside, the breaker was on, the surge protector was showing the correct LED colors.  Flipped the breaker off and on, no CLUNK of the ATS.  The good news was the generator and inverter worked. 

I drove to tonight's park, all the while thinking how to trouble shoot this.  It had to be the leading ATS.  The next one in line was working, it clunked for the generator,  and the third one was working with the inverter.  I was thinking the most likely problem was the voltage sense device, that orange box that tells the ATS if the voltage is within the safe range.

And looking back, my neighbor had an external EMS, and it's light show was different when I left than earlier when I had power.

I guess I was right, but the problem was not the orange box, the park voltage must have been out of range and my smart ATS refused to activate.

Your surge protector should have done the same thing (especially since your neighbor's external one possibly indicated an issue).  What brand/model surge protector do you have?  Might be time to consider a replacement.

BTW those orange boxes (if they are the ones I am recalling from the Maverick transfer switch) have variable settings, but you need a certified calibration device to set them (so don't attempt to do it yourself).
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Chasing my tail: No AC shore power

Reply #6
It happens more often than you think.  Years ago I moved my machine shop into the new building, so new the electricity was still being run.  I asked the electrician what was up and he showed me what he'd found: 11,800 volts connected directly to the main panel in the building.  Amazing how fast Public Service of New Hampshire can move when it's not only their fault but a life safety issue.
If there was 11,800 volts in equipment that was not made for it I am amazed that the equipment did not blow up. That electrician is also lucky that he did not blow himself up checking since he was not expecting that voltage.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Chasing my tail: No AC shore power

Reply #7
I had my Maverick orange boxes recalibrated by FOT last year. That's why I just have s simple lightning protection surge protective, Zprogressive Dynamics.

I have the parts to make a 50A power tester, a 50A to twin 15A pigtail and two monitors, see attachment.

I do have one made up for 30A, just a monitor plugged into. 30/50 adapter

But it wouldn't have prevented whatever happened in the middle of the nightt
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer