How can I monitor my Camper trailer voltage? (1 Viewer)

[Fisher23]

I have an Anderson 50 amp plug that goes to my trailer dc-to-dc charger charging my battery running my fridge that is in the trailer.

I want a wire running to the trailer so I cam monitor my voltage on the batteries running the fridge.

Should I use a 2nd mini Anderson connector I can run so I can monitor the batteries in the trailer when enroot or what is a good way to do this?

 

[FrazzledHunter]

You could run a wire but you might get a false low reading due to resistance on a long line from trailer to your tow vehicle's dash.

I'm looking at systems like this for monitoring:
Monitor Station – RV Whisper - https://rvwhisper.com/monitor-station/

I might do it DIY by putting WiFi in the trailer and using smart things.
the idea would be if the RV were stored in an area that had WiFi then I could monitor it from anywhere as well as on the road.

 

[spressomon]

No mention of distance between battery and where you would be...but if within 20' or so, ala Bluetooth, a Victron Smart Battery Sense works for me/my set-up.

Smart Battery Sense - Victron Energy

Improve the charging-efficiency and prolong the life of your batteries with the Smart Battery Sense. Find a dealer near you.

www.victronenergy.com

 

[Fisher23]

Thanks for the tips on the RV Whisper Monitor Station and Smart Battery Sense. I'll see if I can use those and if they have some kind of alarm if I get a voltage drop.

My concern is if voltage in the fridge drops below the amount need to run the fridge.

I was thinking of putting a voltage indicator up on the dash of my LC200 that way it is always visible. An app could be good if it has an alarm.
My fridge has an app that shows voltage, but it doesn't have an alarm on the app.

If I run a hard wire it needs to go from the dash to the trailer batteries. Likely 25 feet. Maybe I'm just too old school.
Even with the distance a 12 gauged wire would let me know the voltage "good enough" where if there was some drop I would know what that difference was.

The Anderson connection connects to the trailer Red Arc system so I cannot use those wires to measure the battery level that is working the fridge in the trailer.

I have had dc-to-c charges break on trips before. The companies warrantee them BUT it can ruin a trip if not monitored.

 

[peesalot]

What fridge ? I had to get a fridge recently, found a good deal on a 45platinum engel (2022) , great but I wish it had the phone app which most do now.
I think Ironman sells a dealo that you plug into fridge and it is similar to the Victron posted above, thers a number of those style monitors on amazon.
FWIW if you have an older fridge with no voltage cut off as I did I would get some type of monitor as you are looking for because running the fridge on low voltage can damage them and its hard to tell, I would notice it cycling often and thats one of the main factors I upgraded, the newer engel has the cut off built in.

 

[Shoredreamer]

If all you need is voltage, I would just run a 12-16 gauge single wire, loomed with your trailer harness. No need to add a second SB50, its a bit overkill just to monitor V. You just need trailer positive back to the dash. Pull ground from anywhere, as it should be common between vehicle and trailer battery. Most of the bluetooth monitors are cool in that they include additional information like discharge in amps, state of charge, temperature etc..

 

[ntsqd]

I would reference ground near the battery so that any resistance in the ground path doesn't skew the results. As has been said if you only need a voltage reading and not any current then the wires can be small because there won't be any current induced voltage drop. For voltage sense wires I think that they can be down in the 18-20 gauge size.

 

[LandLocked93]

Wait, your fridge has an app...that tells you the voltage...of it's source power yes?
That would be the battery powering it. Or am I missing something?

As a RedArc user, I can assure you it will not fail. If it does, it would be a most exceptional case.
And it's charge profiles for the batteries in your camper can be relied upon for solid voltage assurance. So long as your truck is running those batteries are getting 'bulked', 'absorbed', or 'floated' as necessary to keep them in top shape. Put another way, there is no concern of a low voltage condition while the engine runs.

Now tho, when parked up or at camp...where there is a non-renewed drain (current demand) on the batteries to run the fridge and where you would not be in the truck to see any sort of display - should you install one - of battery charge level...that's where I recommend focusing the solution instead.

Unless, again, I'm missing something.

 

[ntsqd]

Victron's line of products also does Bluetooth stuff. I use a Star Trek Communicator (intentionally) so I don't know much about that sort of thing, but I'm told that it's highly helpful and useful.

 

[LandLocked93]

I use a Star Trek Communicator (intentionally)

+1

 

[e9999]

if your concern is actually the fridge temperature getting higher because it's no longer working because of low voltage, then another way to go would be to measure the temperature in the fridge and send that info over wirelessly. Easy to do for $15 with an alarm on the app (see my thread on remote temp sensors). Benefit: shows directly whether the fridge is getting warmer. Downside: will not facilitate preempting of the fridge stopping to work.

 

[ntsqd]

We use a typical indoor/outdoor electronic thermometer to monitor the fridge temp in our pop-top camper.

 

[e9999]

The Victron SmartBatterySense has a decent range actually (not the case for all their bluetooth products unfortunately). It should do 25+' in the open, but that may be affected by surfaces in between the transmitter and the receiver of course. Unfortunately, from recollection alone I do not think the basic Victron Connect app has an alarm feature for voltage but maybe the VRM has it, but that's a different kettle of fish. Sure, a thin wire for voltage reading to the cab would work fine, but that is a pain to wire and a basic readout may not have an alarm feature either. I'm now tempted to go wireless for everything, brain frying be damned...

The high temp app alarm should be enough to avoid problems if you set it low enough that the food won't be damaged. Should still give you time to deal with the voltage. And the range on my wireless temp sensor is very impressive.