I just completed upgrading the converter in the b190 and adding a trimetric monitor. The installation went well and the trimetric is reading volts and amps for the house battery.
Upon completion I did a post installation test of the circuits to make sure they were all operational. They were. However, I noticed that the Trimetric was not sensing amps being drawn for the circuit connecting the lights over the couch and the lights in the overhead bunk. I believe these are all on the same circuit.
My question is, has anyone else who installed a trimetric monitor run into this situation and how they corrected it?
Thanks for any help with this.
Mike
Trimetric installation
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Kentuckian
- Seasoned Traveler
- Posts: 346
- Joined: Sun Sep 30, 2012 3:52 pm
- B190 Year: 1993
- WBCCI: 0
- Location: Kentucky, USA
Re: Trimetric installation
Hi Mike,
I use a Trimetric. I have not experienced the problem that you are reporting. My lights have LEDs in them and even with the lower amp draw they still show up clearly on my Trimetric.
Do you see the Trimetric responding to any other electrical loads in the RV? For example, if you turn on your ceiling ventilation fan do you see amp draw? Depending on your model, if your fan is on full power, you should see consumption of a couple of amps.
If you do not see amp draw with any other electrical items in the RV, I would double check to make sure you have the Trimetric's shunt wired to the correct battery. The starter battery in my '93 is under the hood in front of the driver. The "house" battery is under the hood in front of the passenger. The Trimetric's current shunt needs to be wired to the "house" battery under the hood in front of the passenger. The Trimetric second battery sensor wires should be wired to the "starter" battery.
I use a Trimetric. I have not experienced the problem that you are reporting. My lights have LEDs in them and even with the lower amp draw they still show up clearly on my Trimetric.
Do you see the Trimetric responding to any other electrical loads in the RV? For example, if you turn on your ceiling ventilation fan do you see amp draw? Depending on your model, if your fan is on full power, you should see consumption of a couple of amps.
If you do not see amp draw with any other electrical items in the RV, I would double check to make sure you have the Trimetric's shunt wired to the correct battery. The starter battery in my '93 is under the hood in front of the driver. The "house" battery is under the hood in front of the passenger. The Trimetric's current shunt needs to be wired to the "house" battery under the hood in front of the passenger. The Trimetric second battery sensor wires should be wired to the "starter" battery.
1993 Airstream B190
-
Kentuckian
- Seasoned Traveler
- Posts: 346
- Joined: Sun Sep 30, 2012 3:52 pm
- B190 Year: 1993
- WBCCI: 0
- Location: Kentucky, USA
Re: Trimetric installation
Mike,
One other suggestion. Make sure that the converter and generator are turned off when you check your measurements. The Trimetric will report the "net" power draw on your circuit. So if your lights draw about 1 amp/hour from the battery and if the converter is applying 1 amp/hour back to the battery the Trimetric will report little to no current flow.
One other suggestion. Make sure that the converter and generator are turned off when you check your measurements. The Trimetric will report the "net" power draw on your circuit. So if your lights draw about 1 amp/hour from the battery and if the converter is applying 1 amp/hour back to the battery the Trimetric will report little to no current flow.
1993 Airstream B190
Re: Trimetric installation
Kentuckian,
Thanks for the reply.
I do see amp draw on other circuits. For example, the water pump, overhead fluorescent in front of the ac and new circuits I installed as part of upgrading the converter. So I don't think the shunt is wired incorrectly. Here's a subset of the overall wiring plan I followed.
In the spring, I will install a second battery bank but have installed the battery switch already but the only battery in place is the existing house battery under the hood.
As you can see from the wiring diagram, I removed the negative battery cable running into the converter and routed it to the battery side of the shunt.
I then routed the charge/load side of the shunt into a 150amp negative bus bar which is where I consolidated the negative leads for the new circuits I added. I also routed a negative lead that originally terminated to the negative post on the fuse block in the converter to the negative bus bar I added. This negative lead is routed into a wire loom with a bunch of other wires to the back of the b190.
The bus bar is then connected to the negative battery post on the fuse block in the converter.
Based on my read of the trimetric installation manual this should be correct. The only thing I can figure is there is another circuit ground point which did not route back to the converter. Thus not registering any amp draw on the trimetric since since the negative lead for this circuit is not routed thru the shunt. Just a guess.
Just for clarity I installed a trimetric 2025rv.
Hopefully this additional info will help. I'm still at a loss so more noodling will be required.
Mike
Thanks for the reply.
I do see amp draw on other circuits. For example, the water pump, overhead fluorescent in front of the ac and new circuits I installed as part of upgrading the converter. So I don't think the shunt is wired incorrectly. Here's a subset of the overall wiring plan I followed.
- Partial converter upgrade wiring diagram
- image.jpg (109.49 KiB) Viewed 12265 times
In the spring, I will install a second battery bank but have installed the battery switch already but the only battery in place is the existing house battery under the hood.
As you can see from the wiring diagram, I removed the negative battery cable running into the converter and routed it to the battery side of the shunt.
I then routed the charge/load side of the shunt into a 150amp negative bus bar which is where I consolidated the negative leads for the new circuits I added. I also routed a negative lead that originally terminated to the negative post on the fuse block in the converter to the negative bus bar I added. This negative lead is routed into a wire loom with a bunch of other wires to the back of the b190.
- image.jpg (113.65 KiB) Viewed 12261 times
- image.jpg (109.47 KiB) Viewed 12261 times
Based on my read of the trimetric installation manual this should be correct. The only thing I can figure is there is another circuit ground point which did not route back to the converter. Thus not registering any amp draw on the trimetric since since the negative lead for this circuit is not routed thru the shunt. Just a guess.
Just for clarity I installed a trimetric 2025rv.
Hopefully this additional info will help. I'm still at a loss so more noodling will be required.
Mike
Re: Trimetric installation
Mike,
I think it likely that there is at least one other ground point from the house battery. In my 1993 Airstream 190, while the house battery was in the engine compartment (I now have three 100-Ah AGM batteries under the couch instead), I had the house battery grounded to the vehicle body with a heavy, short (6") cable; that was its ONLY ground.
With your current setup you'd miss measuring any device that grounds to the body. If nothing else, this would likely include the alternator (when the engine is running), which can contribute 40+ amps to the house battery.
Ideally, the shunt would go right next to the battery.
Eric.
I think it likely that there is at least one other ground point from the house battery. In my 1993 Airstream 190, while the house battery was in the engine compartment (I now have three 100-Ah AGM batteries under the couch instead), I had the house battery grounded to the vehicle body with a heavy, short (6") cable; that was its ONLY ground.
With your current setup you'd miss measuring any device that grounds to the body. If nothing else, this would likely include the alternator (when the engine is running), which can contribute 40+ amps to the house battery.
Ideally, the shunt would go right next to the battery.
Eric.
Re: Trimetric installation
Eric,
Where did you ground the batteries under the couch?
I see your point about the way I have the shunt is wired. Not sure how toes silt correct this though given the current setup with the house battery upfront.
When I add three 100amp AGM batteries (1 under the couch. 2 under the stove) I'll look at grounding the batteries in the back where you did and ditch the house battery under the hood. Then the only thing coming from the front would be the charge current from the alternator. I'll have to make a couple of cable swaps at the shunt but I think this would be pretty straight forward change and would solve the problem. I'll post a wiring diagram revision to better visualize what I'm thinking in a couple of days.
Thanks for helping me work through this!
Mike
Where did you ground the batteries under the couch?
I see your point about the way I have the shunt is wired. Not sure how toes silt correct this though given the current setup with the house battery upfront.
When I add three 100amp AGM batteries (1 under the couch. 2 under the stove) I'll look at grounding the batteries in the back where you did and ditch the house battery under the hood. Then the only thing coming from the front would be the charge current from the alternator. I'll have to make a couple of cable swaps at the shunt but I think this would be pretty straight forward change and would solve the problem. I'll post a wiring diagram revision to better visualize what I'm thinking in a couple of days.
Thanks for helping me work through this!
Mike
Re: Trimetric installation
Mike,
I have very large cables (4/0; nearly 1/2" in diameter) running from the battery bank to the shunt and from the shunt to a PROsine 2000 inverter/charger. (The heavy cables are because the inverter can draw many hundreds of amps.)
I then have smaller cables from the shunt to the fuse box and from the shunt to the vehicle chassis.
In your case, a short-term solution might be to move the shunt to the engine compartment (right next to the battery) and run the TriMetric signal wires a longer distance. (I know this would be a hassle.)
Eric.
I have very large cables (4/0; nearly 1/2" in diameter) running from the battery bank to the shunt and from the shunt to a PROsine 2000 inverter/charger. (The heavy cables are because the inverter can draw many hundreds of amps.)
I then have smaller cables from the shunt to the fuse box and from the shunt to the vehicle chassis.
In your case, a short-term solution might be to move the shunt to the engine compartment (right next to the battery) and run the TriMetric signal wires a longer distance. (I know this would be a hassle.)
Eric.
Re: Trimetric installation
Eric,
What I've got in place is simply phase 1 for adding more house battery capacity. I can't really justify adding 3 AGM batteries now just to place the b190 in storage for 5 months. So I added the major components: battery switch, shunt, converter upgrade and trimetric monitor, etc now so in the spring all I need to do is add the batteries and wire them to the components I added this fall. As part of this effort I was performing tests to ensure that I hadn't made any wiring errors. It was this effort which identified the trimetric anomalies. So I guess the testing worked and you have helped me get a better understanding of how to wire the shunt. Thank you for the help.
When all the batteries are in place, the battery under the hood would be separated from batteries in the back effectively creating 2 separate battery banks which are used separately or in combination based on the battery selector switch. The trimetric will be used to monitor the batteries I the back. I would also use the trimetric simply to monitor the voltage of the current house battery under the hood. So what I have now is temporary.
I'm still curious how you got to ground from under the couch? Did you drill a hole to get to the chassis or there an easily accessible ground point under the couch?
You said the chassis ground cable was only 6" long which makes me think it's in the compartment somewhere like maybe the converter chassis, generator housing or seatbelt bolts. Any insight into this would be appreciated.
Mike
What I've got in place is simply phase 1 for adding more house battery capacity. I can't really justify adding 3 AGM batteries now just to place the b190 in storage for 5 months. So I added the major components: battery switch, shunt, converter upgrade and trimetric monitor, etc now so in the spring all I need to do is add the batteries and wire them to the components I added this fall. As part of this effort I was performing tests to ensure that I hadn't made any wiring errors. It was this effort which identified the trimetric anomalies. So I guess the testing worked and you have helped me get a better understanding of how to wire the shunt. Thank you for the help.
When all the batteries are in place, the battery under the hood would be separated from batteries in the back effectively creating 2 separate battery banks which are used separately or in combination based on the battery selector switch. The trimetric will be used to monitor the batteries I the back. I would also use the trimetric simply to monitor the voltage of the current house battery under the hood. So what I have now is temporary.
I'm still curious how you got to ground from under the couch? Did you drill a hole to get to the chassis or there an easily accessible ground point under the couch?
You said the chassis ground cable was only 6" long which makes me think it's in the compartment somewhere like maybe the converter chassis, generator housing or seatbelt bolts. Any insight into this would be appreciated.
Mike
Re: Trimetric installation
Here's a much simpler diagram then the one posted in the top part of this topic
Please note the 2 batteries (battery bank 2) and all the dashed red and black lines will be installed in the spring as phase 2 of this electrical upgrade project. The black line running from the frame ground thru the power post to the shunt is in place today. This is the configuration which provided the odd trimetric amp readings which caused me to open this topic.
With your post above and a careful re-read of the trimetric installation instructions I believe the errant reading resulted from the attachment of the frame ground wire to the battery side of the shunt. Since battery bank 2 is not installed yet and this is the battery bank I wish to ultimately monitor via the trimetric by attaching the frame ground where I did some circuits could not be measured.
To correct this I think all I need to do is install battery bank 2 and attach its neg.wire to the battery side of the shunt (dashed black line), remove the wire currently running from the power post to the battery side of the shunt (solid black line with red xxx running thru it) and attach a wire running from the power post to the load side of the shunt (yellow line).
Mike
- Revised wiring diagram
- image.jpg (71.41 KiB) Viewed 12217 times
With your post above and a careful re-read of the trimetric installation instructions I believe the errant reading resulted from the attachment of the frame ground wire to the battery side of the shunt. Since battery bank 2 is not installed yet and this is the battery bank I wish to ultimately monitor via the trimetric by attaching the frame ground where I did some circuits could not be measured.
To correct this I think all I need to do is install battery bank 2 and attach its neg.wire to the battery side of the shunt (dashed black line), remove the wire currently running from the power post to the battery side of the shunt (solid black line with red xxx running thru it) and attach a wire running from the power post to the load side of the shunt (yellow line).
Mike
Last edited by Mgittrich on Fri Oct 11, 2013 9:16 pm, edited 1 time in total.
Re: Trimetric installation
Mike,
At first I thought there was something wrong with the plan you describe, but after staring at it, I'm not seeing anything. There needs to be exactly one wire between the battery negative post and the shunt, and absolutely nothing else connected on that side of the shunt, but your plan is okay in that regard. It's worth thinking about alternator charge current, and how that will get to each of the two battery banks.
In answer to an earlier question: I'm afraid I don't remember where I grounded my under-couch battery bank. I'll let you know after I've had a chance to take a look (but it might be awhile). The 6" chassis ground cable I was talking about, however, was in the engine compartment when I had a battery there, not under the couch.
Lastly, if you're going to use the Sears Diehard PM-1 batteries (as I did), watch for a sale; they can get pretty cheap.
Eric.
At first I thought there was something wrong with the plan you describe, but after staring at it, I'm not seeing anything. There needs to be exactly one wire between the battery negative post and the shunt, and absolutely nothing else connected on that side of the shunt, but your plan is okay in that regard. It's worth thinking about alternator charge current, and how that will get to each of the two battery banks.
In answer to an earlier question: I'm afraid I don't remember where I grounded my under-couch battery bank. I'll let you know after I've had a chance to take a look (but it might be awhile). The 6" chassis ground cable I was talking about, however, was in the engine compartment when I had a battery there, not under the couch.
Lastly, if you're going to use the Sears Diehard PM-1 batteries (as I did), watch for a sale; they can get pretty cheap.
Eric.
Re: Trimetric installation
Eric,
Thanks for the reply and looking at this for me!
In regards to the alternator current getting to the battery bank in the back this is how I think this will work. When the engine is running the battery under the hood gets charged via the alternator. No change for airstream original design. The battery cable routed back to the converter also carries the alternator current. In my case after the modifications I've already made the battery cable has been routed to a Bluesea battery selector switch which has 4 options: OFF, BAT1, BAT2, BAT1+BAT2.
In OFF is selected, both battery banks are disconnected from each other and the fuse block. Great for storage. BAT1 will continue to charge just like normal if the engine is running.
If BAT1 is selected, the battery under the hood powers the fuse block and carries alternator current. This is equivalent to the original design the path is just a little longer. The generator and shore power would also charge the battery under the hood via the converter. The BAT2 bank is not charged or discharged.
If BAT2 is selected, the battery bank in the back powers the fuse block. No alternator current routes to this battery bank since it is isolated from BAT1 by the battery selector switch. If the generator or shore power are connected BAT2 is charged via the converter. BAT1 is not charged or discharged. However, if you were to start the engine while running the generator or plug into shore power both batter banks would charge. BAT1 via the alternator and BAT2 via the converter.
If BAT1+BAT2 is selected. Both battery banks are discharged and charged via all sources. This is great for charging both banks while driving but I'm a little concerned about overcharging the battery under the hood since the battery bank in back will be about 6x the capacity of the battery under the hood. I'll have to watch this closely initially. If this is problematic there are serval way to correct. You could add a second disconnect switch next to the battery under the hood or leave the battery selector switch set to BAT2 while driving and start the generator to charge both battery banks as described above.
I think this is how charging will work when I complete this project.
Mike
Thanks for the reply and looking at this for me!
In regards to the alternator current getting to the battery bank in the back this is how I think this will work. When the engine is running the battery under the hood gets charged via the alternator. No change for airstream original design. The battery cable routed back to the converter also carries the alternator current. In my case after the modifications I've already made the battery cable has been routed to a Bluesea battery selector switch which has 4 options: OFF, BAT1, BAT2, BAT1+BAT2.
In OFF is selected, both battery banks are disconnected from each other and the fuse block. Great for storage. BAT1 will continue to charge just like normal if the engine is running.
If BAT1 is selected, the battery under the hood powers the fuse block and carries alternator current. This is equivalent to the original design the path is just a little longer. The generator and shore power would also charge the battery under the hood via the converter. The BAT2 bank is not charged or discharged.
If BAT2 is selected, the battery bank in the back powers the fuse block. No alternator current routes to this battery bank since it is isolated from BAT1 by the battery selector switch. If the generator or shore power are connected BAT2 is charged via the converter. BAT1 is not charged or discharged. However, if you were to start the engine while running the generator or plug into shore power both batter banks would charge. BAT1 via the alternator and BAT2 via the converter.
If BAT1+BAT2 is selected. Both battery banks are discharged and charged via all sources. This is great for charging both banks while driving but I'm a little concerned about overcharging the battery under the hood since the battery bank in back will be about 6x the capacity of the battery under the hood. I'll have to watch this closely initially. If this is problematic there are serval way to correct. You could add a second disconnect switch next to the battery under the hood or leave the battery selector switch set to BAT2 while driving and start the generator to charge both battery banks as described above.
I think this is how charging will work when I complete this project.
Mike