R-pod Owners Forum Homepage

This site is free to use.
Donations benefit a non-profit Girls Softball organization

Forum Home Forum Home > R-pod Discussion Forums > Podmods, Maintenance, Tips and Tricks
  New Posts New Posts RSS Feed: Texman 182g Mods
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

Texman 182g Mods

 Post Reply Post Reply Page  <1 2728293031 33>
Author
Message
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 1307
Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Topic: Texman 182g Mods
    Posted: 12 Mar 2019 at 11:04am
That flashing sure sounds like a spike coming through the tstat 12V logic supply. Could be your ground connection is picking up a transient spike from the DSI high voltage igniter. If you don't have any problems with an isolated 12V supply then that would prove it one way or the other. I'll have to go look where I took my -12V supply connection from, I can't recall right now. 
2015 Rpod 179
2012 Toyota Highlander
Back to Top
texman View Drop Down
Senior Member
Senior Member
Avatar

Joined: 24 Jul 2014
Location: TeXas
Online Status: Offline
Posts: 421
Post Options Post Options   Quote texman Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 2:01pm
i did some testing at lunch.  it is definitely the dsi.  when using the water heater power to power the stat, it flashes the stat, but ignites since it is connected.  checked ground and it was slightly loose and the stat worked the first try so i thought that was it. never worked again after the 1st try using the stat.  tried different grounds too.  when the dsi sends the voltage, it zaps the stat. 

the stat relay is rated at 14volts and 20amps.  so i guess the 10-20k volts for spark zaps it. 

so next step is maybe put the stat on a different line of the water heater system that doesn't carry the dsi.  or, different stat?
TexMan 2015 182g
2018 Sequoia
TexManMods
Back to Top
podwerkz View Drop Down
Senior Member
Senior Member
Avatar

Joined: 11 Mar 2019
Location: Texas
Online Status: Offline
Posts: 188
Post Options Post Options   Quote podwerkz Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 2:01pm
Originally posted by texman

Do inverters draw current even when switched off?

I'm new on this forum, but I can help with this.

Most inverters do draw a small amount of current even when completely turned off. Like a modern TV, there are circuits that need power even when the unit is off.

In a typical inverter, the power mosfets, bias circuits, and input filter caps draw a very small amount of current even if the power switch is off. Think about it, that little switch can never handle or directly control the 20-100 amps that the inverter might pull when under load. 

The little rocker or push button switch only turns the control board on, not the power mosfets that actually do the 'heavy lifting'. This is why most inverters will make a tiny spark, snap, or arc when first connecting power, even when the switch is off.

BTW, I just bought my new r-pod from Custom RV in Amarillo and have read this entire thread...I see the work involved and I'm impressed. 

I will start modding my pod very soon.


r・pod 171
Back to Top
texman View Drop Down
Senior Member
Senior Member
Avatar

Joined: 24 Jul 2014
Location: TeXas
Online Status: Offline
Posts: 421
Post Options Post Options   Quote texman Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 2:03pm
thanks for the feedback and welcome to the forum.  it is fun.  just wishing the weather would give us a break so we could be camping.  
TexMan 2015 182g
2018 Sequoia
TexManMods
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 1307
Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 2:28pm
texman, did you check to see whether the tstat gets whacked from the 12V power to the stat even if the relay isn't being used? In other words, remove the two wires from the tstat relay terminals, jumper them together, leave the tstat power terminals connected, and then turn the water heater on from the wall switch. Check to see if the tstat is stable under that condition. 

What I'm trying to determine is whether the relay contacts being connected to your dsi is causing the problem or whether it is the 12V power to the tstat logic circuit?


2015 Rpod 179
2012 Toyota Highlander
Back to Top
texman View Drop Down
Senior Member
Senior Member
Avatar

Joined: 24 Jul 2014
Location: TeXas
Online Status: Offline
Posts: 421
Post Options Post Options   Quote texman Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 2:33pm
yes i tested that.  it is stable and unaffected when not using the relay.  
TexMan 2015 182g
2018 Sequoia
TexManMods
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 1307
Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 4:44pm
Interesting. I keep returning to the point that my tstat isn't showing this behavior.  

So you're having an isolation problem within your tstat boards that I'm not having. That could be because your relays or tstat boards are less well isolated than mine are or you're getting a larger voltage spike hitting your relay than I am. But relays are usually well isolated between the coils and the contacts. The voltage spec limit on the relay that you're looking at is there to keep the contacts from welding closed or burning up when the voltage appears across them as they open and close, its not the spec for isolation between the relay coil and the contacts.  

It could also be the traces on the circuit board itself are allowing a connection. There are multiple manufacturers of these little tstat boards so it could be some are better isolated than others. You may want to use an ohmmeter to check (with no wires connected) if there is any connection between either of the relay terminals and either of the logic power terminals. You can also flip the baord over and check between the points where the relay coils are soldered to the boards and the relay terminals.  If you see anything other than an open circuit (megohm range readings) between any of those points let me know and I'll check mine for comparision. 

If we determine that your tstat relays are as well isolated as mine are it could be that your igniter electrode is cracked or has carbon buildup (like the roubleshooting guide warns) or your dsi board is leaky and one or the other is putting too much voltage back onto the circuit, which is arcing across the traces or between the coil and the contacts. You might even see the arc if you turn out the lights at night and then turn on the water heater. 
2015 Rpod 179
2012 Toyota Highlander
Back to Top
podwerkz View Drop Down
Senior Member
Senior Member
Avatar

Joined: 11 Mar 2019
Location: Texas
Online Status: Offline
Posts: 188
Post Options Post Options   Quote podwerkz Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 4:57pm
Originally posted by texman



The real question for me now is will my currently applied materials withstand highway speeds, rainy highways, etc. and not fly off on the interstate and cause who knows what when a 10 sq ft piece of insulation and landscape fabric appear out of nowhere to a driver behind me?  i am not confident enough to try it in its current state. 

So i have to cover what i have with the TPO (or something else) which is doable i think or start over and go to foam.  But at least i wouldn't really have to worry about the foam coming loose if the tank was flame treated and had a proper bond and i could insulate that upper third.  I dont think the upper 1/3 or 15% is going to make a noticeable and measurable difference really, just trying to talk through all this and make sense of it and give you folks something to read.  Especially if i wrap it again like i said.

Still contemplating but i am leaning towards trying to at cover what i have and go camping. Smile

I would consider applying the foam or boards or mats or whatever, then, after that work has cured, wrap the belly of the tank with a big sheet of hardware cloth (or wire fence) bending it up, forming it, and fastening it along the frame and cross beams, using clamps or self-drilling screws or any other suitable method.

The hardware cloth formed around the tank and foam would hold the foam or other material even if it became damaged or the adhesive let loose. It would also provide some measure of protection from road debris, and will self-drain when wet. 

You can buy vinyl coated hardware cloth and wire fence that will be less resistant to rust, and its all fairly easy to cut and shape, just be sure to wear leather gloves while cutting and bending it. 
r・pod 171
Back to Top
texman View Drop Down
Senior Member
Senior Member
Avatar

Joined: 24 Jul 2014
Location: TeXas
Online Status: Offline
Posts: 421
Post Options Post Options   Quote texman Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 5:02pm
TexMan 2015 182g
2018 Sequoia
TexManMods
Back to Top
texman View Drop Down
Senior Member
Senior Member
Avatar

Joined: 24 Jul 2014
Location: TeXas
Online Status: Offline
Posts: 421
Post Options Post Options   Quote texman Quote  Post ReplyReply Direct Link To This Post Posted: 12 Mar 2019 at 8:43pm
I am getting some flash results when not using relay. Not every time but maybe 50%. Tried different grounds again too. So I am guessing the dsi spark is leaking somehow?i even had a few flashes to the second stat which is close to the module board. Once I moved boards further from module and heater body seemed to help while not using relay. Retried relay and immediate flash when call for spark.
TexMan 2015 182g
2018 Sequoia
TexManMods
Back to Top
 Post Reply Post Reply Page  <1 2728293031 33>

Forum Jump Forum Permissions View Drop Down

Bulletin Board Software by Web Wiz Forums® version 9.64
Copyright ©2001-2009 Web Wiz