Electrical issue-Shore power problem/Generator ok

[bjeder2]

2015 38RL Redwood - We are full time at a campground. Power started going on and off yesterday on shore power. Pedastal at campground thoroughly checked and plug replaced.
We hear a click before power goes out - then it cycles back on for a short while, then goes out again.
We have a Magnum MMS 1012 that had problems in the past and will be replacing this.. It was suggested that the transfer relay?? for the shore power could be bad. The generator runs everything perfectly.

Where is that located and any other suggestions?

[travelin' texans]

Originally Posted by bjeder2

2015 38RL Redwood - We are full time at a campground. Power started going on and off yesterday on shore power. Pedastal at campground thoroughly checked and plug replaced.
We hear a click before power goes out - then it cycles back on for a short while, then goes out again.
We have a Magnum MMS 1012 that had problems in the past and will be replacing this.. It was suggested that the transfer relay?? for the shore power could be bad. The generator runs everything perfectly.

Where is that located and any other suggestions?

Do you have a surge protector/EMS, hardwired or portable, connected to the incoming power? If so the voltage could be dropping or spiking causing the EMS to shut off power briefly to protect your electronics, as designed, then come back on. If you don't have the EMS, you should!!

[almcc]

If you have a surge guard it could be protecting you. Had this issue in a National park with bad power, if we ran some high energy consuming appliances the voltage would drop below the min the surge guard limit and the surge guard would shut off the power, the voltage then came back up then the power was restored after the 2 minute delay the protects and A/C units running. I confirmed the low voltage with my meter.

[Ford truck guy]

I agree with the surge guard protecting you, BUT... I also hear a click when my Transfer Switch engages.. I wonder if your transfer switch is going bad?

[Smoggy]

We just experienced this problem last month and ended up having to replace our onboard surge protector and haven't had an issue since the change out; knock on wood.....

[Terry S]

Had a similar problem to what you described back a few years ago. I have a similar set up, e.g. on board voltage monitoring system, generator, magnum inverter/converter... System would trip out and I thought it was the voltage monitoring system. That was partially correct but not the root issue.


Turned out the that the who ever installed the main shore power receptacle did not correctly tighten down one of the lugs to the main wires. The result is that when you have light loads everything was fine. When there was a heavy load the weak connection would heat up and fail. This caused a lower voltage in one of the lines. The power protector would do it's job and drop the shore power load. The plug would cool and appear to go back to normal until the next heavy load on that circuit. Sometimes a visual inspection will reveal discoloration around a lug or the conecting prongs from the overheating. Finally figured it out, fix was simple, replaced the $30 main shore power receptacle on the camper.


Recommend that you or an electrician check all the main wire lugs for tightness paying particular attention to the ones on the main shore power receptacle, voltage monitoring unit, transfer switch, and inverter/converter. Wire lugs not tightened in residences is a common issue think about wires jostling around in a camper.

[BLeverenz]

We have the same unit. Lost all power to the trailer. In our case it was an intermittent in the shore power cord electric hose reel. Power would go on/off as I pulled the cord off the reel. Fix was tightening electrical connections within the reel. Since you hear a clicking sound before losing power... probably not the same issue. The transfer switch is located in the front storage compartment... above the generator bay. Good luck!

[Cactusjack]

Regarding your electrical problem with Shore Power “clicking” off and defaulting to Generator. I have worked and installed generators and transfer switches on 3 of my personal RV’s over the past 20 years and 2 of my friends. The high majority of the time the failure you have described comes down to is a faulty “Transfer Switch”. All RV’s have this switch and on the Redwoods they are sometimes located above your battery area on the Firewall in front of the basement. Transfer switch failure over time is quite common since it is a mechanical device (thus the click sound you hear) and it typically defaults to the generator side when going bad.

If you have a good grounding in electrical repairs (don’t try this otherwise) you can validate this failure by using a good volt meter. Measure voltage at the Park Power Box, Measure voltage at your surge protector and the input side of transfer switch. If there is voltage at these points, but no voltage on the output side of the transfer switch then it is a transfer switch failure. I hope this helps since again transfer switches fail more often then people may think.

[r time soon]

Cactusjack. While I agree their clicking is probably from the transfer switch I disagree that all RV’s have a transfer switch. Typically they are installed on Generator prep and Generator installed units. Depending on the brand of transfer switch usually just the main board can be replaced to repair the switch to proper operating condition at a lesser cost than replacing the entire switch.

[Cactusjack]

Thank you for your comments back to my response. I am also very much aware that you must have a generator built-in to exercise a transfer switch and not all redwoods have them nor any other RV. I obviously should’ve read my response before hitting the send button and I did notice it. I’ve been around the road a few times and know all about that but thank you again for pointing out my mistake.

The essence of my messages is still the same regarding diagnosis. Your response to me is one of the reasons I very seldom enter anything into the website.

[Cactusjack]

To R-time soon, I also forgot to add that replacing the internals of a transfer switch is not always less expensive than buying a new switch. Transfer switches have come down a lot in the last several years and therefore that is not always the obvious answer. In reality with some manufacturers of transfer switches the internals are everything with the exception of the outside case and cable connectors to bring the wiring in. This is especially true if you have no experience in doing these sorts of repairs. My background is in electrical engineering however the three transfer switches I have replaced, it was a whole lot simpler to simply buy a new replacement transfer switch, in some cases less than $200 and install it and be in and out quickly.