Battery Boost

[YC1]

I have replaced thousands of continuous duty solenoids in my service center and most run warm to so hot they will burn your fingers. The Trombetta draws a lot of power and will get very hot.

If they were mounted on a metal surface to provide some heat sink they would last longer.

[Old Scout]

After thinking about this a bit more--one potential problem I see with disconnecting the OEM Vansco system is that you don't have a hi-capacity charging interface between the battery banks. Don't have the specs on the echo charger but it is not a very robust circuit. Accordingly, when you are driving, your chassis bat will have priority from the Cummins alternator [160 DC amps] but limited charge capacity to the house bat, via the echo charger. Conversely, when you are on shore power, your house bats will have priority from your inverter [120 DC amps] but your chassis bats will have limited charging, via the echo charger. So not a big issue for shore power but we often use the alternator to provide 12v DC thru the inverter [120v AC out] so we can run things like the microwave, coffee pot, crock pot, etc, while going down the road....

[pasdad1]

Originally Posted by YC1

I have replaced thousands of continuous duty solenoids in my service center and most run warm to so hot they will burn your fingers. The Trombetta draws a lot of power and will get very hot.

If they were mounted on a metal surface to provide some heat sink they would last longer.

What about using one of these solid stare relays to replace a continuous duty solenoid?

http://www.offroadengineering.com/pr...ontactors.html

[Parkereng]

Originally Posted by Old Scout

After thinking about this a bit more--one potential problem I see with disconnecting the OEM Vansco system is that you don't have a hi-capacity charging interface between the battery banks. Don't have the specs on the echo charger but it is not a very robust circuit. Accordingly, when you are driving, your chassis bat will have priority from the Cummins alternator [160 DC amps] but limited charge capacity to the house bat, via the echo charger. Conversely, when you are on shore power, your house bats will have priority from your inverter [120 DC amps] but your chassis bats will have limited charging, via the echo charger. So not a big issue for shore power but we often use the alternator to provide 12v DC thru the inverter [120v AC out] so we can run things like the microwave, coffee pot, crock pot, etc, while going down the road....

These are good thoughts! In fact if it is true that the alternator charges the chassis battery bank, the echo charger would do nothing to charge house batteries because it is hooked up to charge chassis from house, not the other way around on my unit.

Time to order time to order a new relay. Is one better than the other/ any recommendations out there. Would like direct fit replacement for sure.

Thanks

[YC1]

Pasdad1, I have never had one of those devices to evaluate. It is interesting to see how they could handle so much current in such a small package. I suspect they are a diode based device.

Combiner 100 Sheet

I have this device installed and there is one that will handle much more current. It would be very rare for me to have a deeply charged bank these days. It is not a great idea to use the alternator as the charging source if the coach batteries are low.

The disadvantage of one of these devices is there is no input to shut it off if the generator is running. In some cases you can get an alternator fail light with the engine and generator running. I just put a connector on mine that I can turn it off if necessary. I have not had the issue in years.

[mel s]

If you are going to modify the charging system adding a solid state isolator, (sized to the capacity of the amp output of your alternator), is a simple workable solution.

https://www.youtube.com/watch?v=amvt9S8l3fU

See also:

https://www.youtube.com/watch?v=KjI99caH_hk

[Ken T.]

Originally Posted by Old Scout

Parkereng--didn't catch in your earlier post that you had an after-market echo charger installed on a Vansco coach--clearly the previous owner had a problem with the OEM [Vansco] charging system. Good news is: your Vansco charging logic is still intact; bad news is: it resulted in burnt solenoid contacts. So the root cause persists--suspect the new solenoid will likely fail too.
Ken T.-- the boost switch in my 03 [which I no longer use], has a momentary switch--requires that you hold it down for boost. Recently learned that newer Alpines came with std latching switches that remain closed until you switch them off. Agree--your upgrade basically parallels how my older Alpine works, except that my coach also has a battery isolator to control voltage between banks. Not sure how your upgrade differs from mine--eg. my isolator interacts with alternator [DuVac system] to balance charging/limit one bank from discharging the other.

Basically no difference. I had a switch in my parts bin and did not have an isolator. Since my booster switch is controled by Vasco and I removed the Vasco output to the solenoid the added switch is now my booster switch also.

[Old Scout]

Not to quibble but since your new switch is controlled by Vansco--is it acting more like a relay???? Curious--what is the amp rating on your "switch?" Also, did you use the existing OEM cables between the bat banks to connect the new switch? Guess what I am asking is--given the potential hi-amp nature of charging the bats, how does the durability of your new switch compare to the OEM solenoid you replaced?

[pasdad1]

Originally Posted by Old Scout

Not to quibble but since your new switch is controlled by Vansco--is it acting more like a relay???? Curious--what is the amp rating on your "switch?" Also, did you use the existing OEM cables between the bat banks to connect the new switch? Guess what I am asking is--given the potential hi-amp nature of charging the bats, how does the durability of your new switch compare to the OEM solenoid you replaced?

Originally Posted by Ken T.

I was unsatisfied with the decisions Vasco made relating to the effective charging of my batteries. We boondock an average of about 100 days a year and I have three solar panels. My solution for charging the batteries is as follows:
1. Installed an echo charger to charge the chassis batteries when we are using solar power or plugged in.
2. Disconnected the Vasco output to the solenoid and installed a switch on the dash to energize the solenoid when traveling so I can charge the house batteries with the alternator. The switch could also be used as a booster switch if necessary.

I installed this system about a year ago and it works well. Since the solenoid operation is a manual system I need to remember to turn on the switch when traveling and turn it off when I arrive at my destination.

Old Scout, I believe Ken T is still using his solenoid. It is just activated by a switch on the dash instead of being connected to the Vasco.

[Old Scout]

Got it--no longer impacted by potential Vansco cycling--but still curious about amp load and durability. Understand keeping the new switch on while driving so house bats are charged. Do you also leave it on while on shore power to keep chassis bats charged? If so, you are basically in boost mode most of the time--not an issue, just curious....

[JLMunsil]

It is my understanding that the vansco uses voltage to determine when to combine the battery banks. When one of the battery banks reaches 13 volts the solenoid closes combining the chassis and coach batteries. Both banks will be charged using the charging source available. ( shore power/generator thru the inverter charger or the engine thru the alternator.)
If both banks fall below 13 volts then the solenoid opens and the battery banks are separated.

It is normal for the solenoid to be closed for long periods of time which makes it hot because of the current flowing thru. It is a continuous duty solenoid so it is designed for this use.

The problem with contacts failing is the arching when the solenoid goes off and on. This is ok in normal operation but becomes excessive when one set of batteries is below 13 volts and the other is at 13 volts. The solenoid opens when the batteries fall below 13volts. With the reduced load because of separating the two banks, the batteries will increase to 13 volts again and the solenoid will close. With the increased load because of combining the two banks, the batteries will fall below 13 volts and the solenoid will open again. This will occur when the charging source is not active

This cycling causes the contacts to fail. When the chassis batteries fail because they are not charged when on shore power some install an eco charger to solve the issue. This is ok but they fail to realize that the Eco charger only charges in on direction. It charges the chassis batteries when the coach batteries are being charged. The chassis batteries are also charged when the engine is running. The coach batteries are only charged when on shore power or generator. They are not charged while driving.

When the solenoid is operating properly both battery banks will be charged with the the inventor/charger or the alternator. If the solenoid is not operating properly the chassis batteries will only be charged by the alternator and the coach batteries will only be charged by the inverter/charger.



08 34-ft fdds

[JLMunsil]

The boost switch is a manual option for closing the solenoid. If the solenoid is already closed thru the Vansco then the boost does not do anything. If both battery banks are below 13 volts then the boost switch will close the solenoid and combine the banks.
The solenoid has to be working for the boost switch to combine the banks.


08 34-ft fdds

[Ken T.]

Originally Posted by Old Scout

Got it--no longer impacted by potential Vansco cycling--but still curious about amp load and durability. Understand keeping the new switch on while driving so house bats are charged. Do you also leave it on while on shore power to keep chassis bats charged? If so, you are basically in boost mode most of the time--not an issue, just curious....

Old Scout,
I use an Echo charger to keep up the chassis batteries when generator is running, plugged in or when charging the house batteries with solar. If the chassis batteries needed extra charging I could use the switch but it has never been necessary. The switch I am using is a 20 amp switch which I think is well above the draw of the solenoid coil.

[DrDaveMA]

Originally Posted by JLMunsil

It is my understanding that the vansco uses voltage to determine when to combine the battery banks. When one of the battery banks reaches 13 volts the solenoid closes combining the chassis and coach batteries. Both banks will be charged using the charging source available. ( shore power/generator thru the inverter charger or the engine thru the alternator.)
If both banks fall below 13 volts then the solenoid opens and the battery banks are separated.

It is normal for the solenoid to be closed for long periods of time which makes it hot because of the current flowing thru. It is a continuous duty solenoid so it is designed for this use.

The problem with contacts failing is the arching when the solenoid goes off and on. This is ok in normal operation but becomes excessive when one set of batteries is below 13 volts and the other is at 13 volts. The solenoid opens when the batteries fall below 13volts. With the reduced load because of separating the two banks, the batteries will increase to 13 volts again and the solenoid will close. With the increased load because of combining the two banks, the batteries will fall below 13 volts and the solenoid will open again. This will occur when the charging source is not active

This cycling causes the contacts to fail. When the chassis batteries fail because they are not charged when on shore power some install an eco charger to solve the issue. This is ok but they fail to realize that the Eco charger only charges in on direction. It charges the chassis batteries when the coach batteries are being charged. The chassis batteries are also charged when the engine is running. The coach batteries are only charged when on shore power or generator. They are not charged while driving.

When the solenoid is operating properly both battery banks will be charged with the the inventor/charger or the alternator. If the solenoid is not operating properly the chassis batteries will only be charged by the alternator and the coach batteries will only be charged by the inverter/charger.



08 34-ft fdds

Jim, thank you, you have made sense of what I have been hearing for years. While parked beside the s&b and not plugged in, although I do have the 2 solar panels, periodically I would hear the coach "click", it was loud like a transfer switch loud. Your explanation makes it all fit together. I had the solenoid replaced about 8 years ago when I had tried to use the boost switch and it had not worked. Since then I have installed a power connection for the coach and I do not recall hearing the clicking recently. I need to check to see if the solenoid is still working so if by some chance I do need to bridge the banks I could do it.