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Rocketsled
03-30-2020, 04:41 AM
Spring projects included 2 6v batteries, a new 12v converter, and eventually a power status monitor (gotta figure out where and how to mount the shunt, but that's a different question for a different thread.)

I've seen this display show 3/4 battery when I had the 12v deep cycle battery, but any idea of what it actually thinks 1/4, 1/2, 3/4, etc actually are?

https://i.imgur.com/fmCVw7g.jpg

Logan X
03-30-2020, 05:13 AM
Those lights are just reading the battery voltage. Voltage level = state of charge. The problem with this method is the batteries need to rest with no load on them for about thirty minutes to get an accurate reading. The lights make the reading even more unreliable. I added a picture of battery state of charge by voltage.

You can get a voltage meter to plug into a 12v outlet. Having the actual voltage instead of the lights will give you better information. Something like this-

https://www.amazon.com/LIHAN-Charger-Display-Voltage-Compatible/dp/B01JA627KU

However, as you stated, the best solution is a battery monitor with a shunt. I installed the shunt on the tongue of my trailer in a little weather proof box. It worked out well. Here is a video about it if you want more information-

https://youtu.be/tDJrtC_zRJM

Rocketsled
03-30-2020, 05:46 AM
I’ve seen several charts like that, they seem to be all over the map.

I bought one of these...the price was right and if it’s crap, all the wiring will be in place for a better one. Just not looking forward to running wires from the tongue to the inside, bottom of the trailer is sealed and I don’t wanna mess with it.

Spartan Power DC Meter Battery Monitor & Multimeter 0-100A 6.5V-100VDC LCD Digital Display Comes with 100A Current Shunt https://www.amazon.com/dp/B07FN3VXH4/ref=cm_sw_r_cp_api_i_uFFGEbHJC38YB

roadglide
03-30-2020, 06:40 AM
Login X your chart is comparable with the volt meter I have wired inside my camper . At 12.2 the idiot light will read 2/3 . My system never gets to 1/2 . Personally it’s easier to run a voltmeter With out the amps and shunt . My meter has that option I chose not to Install because of the wiring , my solar charger shows how many amps are going to my battery.

Rocketsled
03-30-2020, 08:07 AM
Knowing the state of wiring in trailers in general, is there a published wiring diagram for these things?

JRTJH
03-30-2020, 08:44 AM
Rocketsled,

First, you won't find a wiring diagram for ANY Keystone RV. If you should "stumble onto such a diagram" you'll have the only one outside of Keystone's "trade secret vault". Keystone has stated repeatedly they do not share wiring or plumbing diagrams with anyone, dealers, customers or competition.

Second. From my experience, I've seen the exact same "voltage idiot light panel" read differently with the EXACT same voltage in the battery. The wiring, resistance within the wiring system, size of wire and "calibration" of the circuit board inside the monitor panel will all have an effect on "how many LED's light at a specific voltage, so the number of lights on YOUR panel may well be different than the number of lights on another panel, even with the SAME battery charge condition.....

The "cheapest" way to monitor voltage is to wire in (or simply plug in) a voltage monitor device. Here are a couple, one is "hard wired" the other is plugged into a 12VDC socket. Both will give you the "voltage on that circuit" (not the voltage at the battery terminals) and should, within reason, give you the "battery charge status" when compared to the chart posted above. If you "print out a copy of the chart, laminate it and "stick it to the wall" above the voltage monitor" you'll have a "quick, down and dirty" method of checking the "generalized, overall charge status" of your battery system.

When you get "right down to the nitty gritty" the question becomes, do you want "EXACTING scientific data" (information overload) or a "quick, down and dirty" means to know if you need to start the generator now or wait a couple more hours.... If your need for information is whether to start the generator at 15:36 versus 15:46, then you need to invest in the "high dollar equipment". If your need for information is whether to start the generator now or wait till evening, you don't need to spend much more than a few minutes and $10-15 on a voltage readout device and a printed voltage chart.

Logan X
03-30-2020, 08:51 AM
I’ve seen several charts like that, they seem to be all over the map.

I bought one of these...the price was right and if it’s crap, all the wiring will be in place for a better one. Just not looking forward to running wires from the tongue to the inside, bottom of the trailer is sealed and I don’t wanna mess with it.

Spartan Power DC Meter Battery Monitor & Multimeter 0-100A 6.5V-100VDC LCD Digital Display Comes with 100A Current Shunt https://www.amazon.com/dp/B07FN3VXH4/ref=cm_sw_r_cp_api_i_uFFGEbHJC38YB

I have my battery monitor display mounted inside the trailer and the shunt is on the tongue. The only wire I needed to run was a data cable. I put the data cable in a protective loom and zip tied it to the propane line under the trailer. I also entered the trailer at the same place as the kitchen propane line so I didn’t drill any new holes. It was pretty easy.

Ken / Claudia
03-30-2020, 09:08 AM
About 3 years ago I was looking at getting away from the lights on the panel. John mentioned the LED plug into socket, at the time I had not known about it. I thought I would need to wire in a display. I would have, but the socket was under 10 bucks and just plug it into a socket I would never use anyway. It is still working great as of today. If it quits I will just order another. For sure there are many better ways to monitor the volts than the outdated panel display, that panel display for me is really like a go/no gauge. .

Logan X
03-30-2020, 09:12 AM
On the topic of reading voltage to measure a batteries state of charge (like using the idiot lights or a digital voltage display) versus using a good battery monitor with a shunt, it a little like towing with a half ton truck.

I mean no disrespect, and this is obviously just my opinion. If you are measuring your batteries state of charge only by reading the voltage and then saying that using a battery monitor with a shunt is unnecessary(or only for show to impress your neighbors) it is a little bit like guys who have only ever towed with a half ton truck and say they don’t feel the trailer behind them.

You don’t know what you don’t know. You don’t know how much easier it is to tow with and HD truck until you’ve tried it. It’s the same with a shunt based battery monitor. Having a good battery monitor has made a huge difference in my ability to camp off grid comfortably. Mine cost $150, so they are not that expensive, and it took about an hour and a half to install, so they are not that hard to install.

If you don’t really camp off grid I would say it was unnecessary, but if you like Boondocking, and especially if you have multiple batteries, a good battery monitor is the first upgrade I would do.

Rocketsled
03-30-2020, 09:46 AM
Rocketsled,

First, you won't find a wiring diagram for ANY Keystone RV. If you should "stumble onto such a diagram" you'll have the only one outside of Keystone's "trade secret vault". Keystone has stated repeatedly they do not share wiring or plumbing diagrams with anyone, dealers, customers or competition.


I expected at much, I was just hoping for an indoor wiring equivalent at the Powercenter...if it's in-line with the negative cable, and that cable runs into the cabin, then I'd rather put it at one end rather than the other. Even if it reads off by 5-10%. It had amperage draw which is also kinda nice to have.

I've got another stub panel with USB and a cigarette lighter plug to top off the CPAP battery...charging at it's native 12v bypasses the inefficiency of getting to 110v just to throw it away at the wall wart and step it back down to 12v.

JRTJH
03-30-2020, 10:47 AM
I expected at much, I was just hoping for an indoor wiring equivalent at the Powercenter...if it's in-line with the negative cable, and that cable runs into the cabin, then I'd rather put it at one end rather than the other. Even if it reads off by 5-10%. It had amperage draw which is also kinda nice to have.

I've got another stub panel with USB and a cigarette lighter plug to top off the CPAP battery...charging at it's native 12v bypasses the inefficiency of getting to 110v just to throw it away at the wall wart and step it back down to 12v.

I'd ask, unless you're trying to be "more focused on energy use than on camping", why would you want to monitor voltage AND amperage ???

I consider that to be "more information that is needed" and more of a "hey look what I can do" than a useful tool. If you consider it like automotive gauges, why monitor oil temperature AND oil pressure? If there's a problem with one, the other will also be changing, and if the oil pressure goes down, or the oil temperature goes up, either one will be the reason to shut down the engine, so monitoring both is, for most people, "overkill".

I can do the same "battery charge assessment/battery use assessment" by checking the voltage without knowing "amp draw". I already know "amp draw" based on knowing the TV is on, draws 70 watts, the fan in the bathroom is on, draws 40 watts and 3 lights are on, drawing 15 watts, so my total watt use is 135 watts (and in my head I can calculate at 13 VDC, that's an amp draw of around 10 amps. No need for a $200 device to do what I can do with a glance....

Now, for troubleshooting or if my BIL just bought a new toy for his RV, I might be inclined to "one up him"... Nah, let him spend his retirement, I'll save mine for fishing lures....

I suppose, what I'm "hinting at" is that "monitoring stuff" is great for the "brand new RV'er who doesn't know his rig, but for most people who have used their RV for more than a year, they already know how long the batteries will last before recharge, they know how long the black tank will last and they know how many days of fresh water they can count on BEFORE they ever leave their driveway.... So, for most people, all the extra monitoring stuff gets used the first few trips, then fades into the background because we "learn" to crank up the generator" the third day for 3 hours and we know that without ever touching that expensive panel. After a few trips, everyone of us knows enough about our energy use and our water use to know how to plan and "survive boondocking" without having to monitor "amp draw" or even "DC voltage output". That's where we get back to "most people ignore all the monitor devices and just enjoy a cold one by the campfire without worrying about battery condition or how many watts the new lights use versus the old lights they replaced because they already know, while setting up their trailer on the campsite that they don't need to unload the generator for 2 more days and they know how many gallons of gas they'll need to keep the batteries charged, when to refill the generator and even when to change over the propane tank...

Rocketsled
03-30-2020, 02:47 PM
Now, for troubleshooting or if my BIL just bought a new toy for his RV, I might be inclined to "one up him"... Nah, let him spend his retirement, I'll save mine for fishing lures....


I have this theory: Some Lures are for catching fish and other lures are for catching people.

I think you're over thinking it. I was reading the topic and the internet said 'You need a system with a shunt for an accurate reading' and it cost all of $18.

It's not like I'm putting in a 6 battery Battleborn system and enough solar to keep them topped off. It was $18 vs $11.

flybouy
03-30-2020, 03:08 PM
First let me premise this with the fact that we only camp with electric as a minimum.

I installed a battery cut off switch and a marine waterproof voltmeter in the battery box lid. The meter is wired to the switched side so it only works when the battery switch is in the "on" position. When I turn the switch on I immediately know the status. I also know if the battery is charged enough to operate the tongue jack, or slides, or if it needs to be charged first. It also let's me know if the charger is working properly.

This works for the way I use it, gives me the information that I need, and was reasonably priced. I suppose if I were boondocking and solar charging I would want more info.

GHen
03-30-2020, 07:28 PM
I use a battery monitor from amazon. Connect Bluetooth to your phone and save data until you connect. It will also chart the voltage over the last 24 hours, you can actually see when your furnace turned on overnight.
Hopefully this link will work.


Battery Monitor BM2 BM3 Bluetooth 4.0 Wireless Battery Tester 12V Automotive Battery Load ... https://www.amazon.com/dp/B07GP1RXYZ/ref=cm_sw_r_sms_tai_9FRGEb...

Keystoned
03-31-2020, 06:56 AM
Got one of these since my usb ports died but the socket didn't...
https://www.amazon.com/gp/product/B07RKP6KWL/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

It reads the same value as the panel outside for the jacks.